Applying iodine fertilizers to cultivate iodine-rich crops for daily intake is an effective approach for iodine supplementation,especially for aromatic rice.Field experiments were conducted during the early growing se...Applying iodine fertilizers to cultivate iodine-rich crops for daily intake is an effective approach for iodine supplementation,especially for aromatic rice.Field experiments were conducted during the early growing seasons of 2021 and 2022 to evaluate the impacts of foliar application of iodine fertilizer on aromatic rice and to explore the optimal iodine fertilizer concentration.At the full heading stage,six different concentrations of sodium iodide solutions of 0%(CK),0.010%(T1),0.025%(T2),0.050%(T3),0.075%(T4),and 0.100%(T5)were applied to indica aromatic rice cultivars Meixiangzhan 2 and Xiangyaxiangzhan.The results showed that sodium iodide treatments significantly increased the iodine and sodium contents in both leaves and grains.Compared with the CK,the T1 and T2 treatments increased the 2-acetyl-1-pyrroline(2-AP)content in mature grains by 8.41%-101.66%and 13.58%-74.60%,respectively.Improvements in the contents of 1-pyrroline-5-carboxylic acid,proline,1-pyrroline,and methylglyoxal,as well as the activity of proline dehydrogenase were also detected.Additionally,sodium iodide treatments remarkably decreased the chalky grain rate,chalkiness area,and chalkiness degree of aromatic rice,with the T2 treatment exhibiting a 17.79%-47.42%decrease in chalkiness degree compared with the CK.Meanwhile,T1 and T2 treatments showed beneficial impacts on chlorophyll content,photosynthetic characteristics,and yield components,while T3,T4,and T5 treatments exhibited adverse effects on leaf and grain yields.The linear discriminant analysis revealed significant differences between treatments.The correlation analysis and piecewise structural equation modeling showed that the iodine and sodium influenced the photosynthetic characteristics and chlorophyll content of the leaves,thereby regulating the 2-AP biosynthesis and yield components,ultimately affecting the 2-AP content and yield.Overall,this study suggests that foliar application of 0.025%sodium iodide is an effective method to enrich the iodine content in rice grains,improve the grain aroma and appearance quality of aromatic rice,without detrimental effects on grain yield.展开更多
Forest gaps are important in forest dynamics and management, but little is known about how soil fauna influence the degradation of recalcitrant litter components in different-sized forest gaps. This investigation uses...Forest gaps are important in forest dynamics and management, but little is known about how soil fauna influence the degradation of recalcitrant litter components in different-sized forest gaps. This investigation uses litterbags with two different mesh sizes (0.04 and 3 mm) to control the meso- and microfauna entering the bags to quantify the contribution of soil fauna to the degradation of recalcitrant components (including condensed tannins, total phenol, lignin and cellulose) during litter decomposition. The experiment was conducted in seven different forest gap sizes in Pinus massoniana plantations over 1 year. One closed-canopy site (CC) and forest gap sizes of 100, 225, 400, 625, 900, 1225 and 1600 m^2 were created in a P. massoniana plantation in the Sichuan basin of China;the CC was treated as the control. Cinnamomum camphora foliage from local native trees was used in all forest gap experiments. We found the following:(1) Gap size had significant effects on the degradation rates (E) of condensed tannins and lignin and on the contributions of soil fauna;medium-sized gaps also presented high degradation rates. Soil fauna obviously contributed to the degradation of recalcitrant foliar litter components in medium-sized gaps.(2) The highest contribution to degradation (40.98%) was recorded for lignin, and the lowest contribution (0.29%) was recorded for condensed tannins. The results indicate that medium-sized gaps (900 m^2) were conducive to the degradation of recalcitrant litter components by soil fauna.展开更多
We estimated water-use efficiency and potential photosyn- thetic assimilation of Holm oak (Quercus ilex L.) on slopes of NW and SW aspects in a replicated field test examining the effects of intensifying drought in ...We estimated water-use efficiency and potential photosyn- thetic assimilation of Holm oak (Quercus ilex L.) on slopes of NW and SW aspects in a replicated field test examining the effects of intensifying drought in two Mediterranean coppice forests. We used standard tech- niques for quantifying gas exchange and carbon isotopes in leaves and analyzed total chlorophyll, carotenoids and nitrogen in leaves collected from Mediterranean forests managed under the coppice system. We pos- tulated that responses to drought of coppiced trees would lead to differ- ential responses in physiological traits and that these traits could be used by foresters to adapt to predicted warming and drying in the Mediterra- nean area. We observed physiological responses of the eoppiced trees that suggested acclimation in photosynthetic potential and water-use effi- ciency: (1) a significant reduction in stomatal conductance (p〈0.01) wasrecorded as the drought increased at the SW site; (2) foliar 813C increased as drought increased at the SW site (p〈0.01); (3) variations in levels of carotenoids and foliar nitrogen, and differences in foliar morphology were recorded, and were tentatively attributed to variation in photosyn- thetic assimilation between sites. These findings increase knowledge of the capacity for acclimation of managed forests in the Mediterranean region of Europe.展开更多
In order to completely evaluate ammonia emission from greenhouse vegetable fields,crop canopy absorption should not be neglected.The foliar uptake of NH3 applied at two growth stages and the subsequent 15N-labeled N t...In order to completely evaluate ammonia emission from greenhouse vegetable fields,crop canopy absorption should not be neglected.The foliar uptake of NH3 applied at two growth stages and the subsequent 15N-labeled N translocation to other plant components were investigated under greenhouse conditions using chambers covered with the soil of a tomato field.Treatments comprised three NH3-N application rates(70,140,and 210 mg/plot) using 15N-labeled ammonium sulfate.Plants were harvested immediately after exposure for 24 h,and the total N concentrations and 15N/14 N ratios were determined.With increased NH3 concentration,total 15NH3-N absorption increased considerably,whereas the applied 15NH3-N uptake decreased gradually.The tomato plants absorbed 33-38% and 24-31% of the 15NH3-N generated at the anthesis and fruit growth stages,respectively.A total of 71-80% of the recovered NH3 was observed in the leaves and 20-30% of the recovered NH3 was remobilized to other components.Among them,an average of 10% of the absorbed 15NH3-N was transferred into the tomato fruits.All these results indicated the potential of the tested tomatoes for the foliar uptake of atmospheric 15NH3 and the distribution of 15N-labeled vegetative N among different plant components.The results are of great importance for the complete evaluation of nitrogen use efficiency in the greenhouse tomato fields.展开更多
Increasing zinc(Zn)concentration in wheat grain is important to minimize human dietary Zn deficiency.This study aimed to investigate the effect of foliar Zn and soil nitrogen(N)applications on the accumulation and dis...Increasing zinc(Zn)concentration in wheat grain is important to minimize human dietary Zn deficiency.This study aimed to investigate the effect of foliar Zn and soil nitrogen(N)applications on the accumulation and distribution of N and Zn in grain pearling fractions,N remobilization,and the relationships between nutrient concentration in the vegetative tissues and grain or its fractions in two cropping years in the North China Plain.The results showed a progressive decrease in N and Zn concentrations from the outer to the inner parts of grain,with most of the accumulation in the core endosperm.Foliar Zn application significantly increased N concentration in the pericarp,and soil N application increased N concentration in each grain fraction.Both treatments significantly increased core endosperm Zn concentration.Foliar Zn had no effect on grain N and Zn distribution.Soil N application made N concentrated in the aleurone,promoted Zn translocation to the core endosperm and also increased N remobilization and its efficiency from the shoot to the grain,but no improved contribution to grain was found.N concentration in grain and its fractions were positively correlated with N in vegetative organs at anthesis and maturity,while positive correlations were obtained between N concentration in the pericarp and progressive central area of the endosperm and Zn concentration in the core endosperm.Thus,foliar Zn and soil N applications effectively increased yield and N and Zn concentrations in the wheat grain,particularly in the endosperm,and could be promising strategies to address Zn deficiency.展开更多
Water deficit is one of the most important causes of decreased yield in cultivated plants. Non-foliar green organs in cotton play an important role in yield formation at the late growth stage. Although better photosyn...Water deficit is one of the most important causes of decreased yield in cultivated plants. Non-foliar green organs in cotton play an important role in yield formation at the late growth stage. Although better photosynthetic performance was observed in a non-foliar organ (bract) compared with leaves under water deficit. However, the physiological response of each organ in cotton to water deficit has not been comprehensively studied in relation to the water status and photosynthesis characteristics. We studied the maintenance of water status of each organ in cotton by measuring their relative water content, proline content and stomatal characteristics. Water deficit significantly decreased the surface area of each organ, but to a lesser extent in non-foliar organs. Our results showed that the relative contribution of biomass accumulation of non-foliar organs increased under water deficit. Non-foliar organs (bracts and capsule wall) showed less ontogenetic decrease in O2 evolution capacity and in RuBPC activity (per dry weight) as well as better antioxidant systems than leaves at various days after anthesis. We conclude that the photosynthesis from non-foliar organs is important for increasing cotton yield especially under water deficit conditions.展开更多
A field study was undertaken to ascertain the effects of elicitors viz. benzothiadiazole (BTH) and salicylic acid (SA) on defense related enzymes viz. peroxidase, phenylalanine ammonia lyase, superoxide dismutase,...A field study was undertaken to ascertain the effects of elicitors viz. benzothiadiazole (BTH) and salicylic acid (SA) on defense related enzymes viz. peroxidase, phenylalanine ammonia lyase, superoxide dismutase, chitinase and 13-1,3-glucanase, and phenols in rice (Pusa Basmati I) plants. First foliar spray of BTH (50 mg/kg) and SA (50 mg/kg) was done at the maximum tillering stage and inoculation with Rhizoctonia solani was carried 24 h after elicitor treatment. Elicitors were further sprayed at every growth stage. Time course analysis showed peak accumulation of defense related enzymes and phenols in the rice leaves treated with BTH and SA, and accumulation was the highest at the flowering stage. Higher enzymatic activity was observed in elicitor treated plants inoculated with R. solani. Compared to the untreated control plants, application of elicitors before R. solani inoculation significantly elicited the defense related enzymes and phenols. Moreover, application of elicitors had a positive effect on yield and disease reduction. It is suggested that pretreatment of rice leaves with BTH and SA could be used to enhance the level of protection against sheath blight and to improve rice yield in the fields.展开更多
Foliar fungal diseases(rust and late leaf spot)incur large yield losses,in addition to the deterioration of fodder quality in groundnut worldwide.High oleic acid has emerged as a key market trait in groundnut,as it in...Foliar fungal diseases(rust and late leaf spot)incur large yield losses,in addition to the deterioration of fodder quality in groundnut worldwide.High oleic acid has emerged as a key market trait in groundnut,as it increases the shelf life of the produce/products in addition to providing health benefits to consumers.Marker-assisted backcrossing(MABC)is the most successful approach to introgressing or pyramiding one or more traits using traitlinked markers.We used MABC to improve three popular Indian cultivars(GJG 9,GG 20,and GJGHPS 1)for foliar disease resistance(FDR)and high oleic acid content.A total of 22 BC3F4 and 30 BC2F4 introgression lines(ILs)for FDR and 46 BC3F4 and 41 BC2F4 ILs for high oleic acid were developed.Recurrent parent genome analysis using the 58 K Axiom_Arachis array identified several lines showing upto 94%of genome recovery among second and third backcross progenies.Phenotyping of these ILs revealed FDR scores comparable to the resistant parent,GPBD 4,and ILs with high(~80%)oleic acid in addition to high genome recovery.These ILs provide further opportunities for pyramiding FDR and high oleic acid in all three genetic backgrounds as well as for conducting multi-location yield trials for further evaluation and release for cultivation in target regions of India.展开更多
[Objectives] The effects of copper-based nutrient foliar fertilizer on photosynthetic characteristics,yield,accumulation and distribution of trace elements in various organs,disease prevention effect and soil enzyme a...[Objectives] The effects of copper-based nutrient foliar fertilizer on photosynthetic characteristics,yield,accumulation and distribution of trace elements in various organs,disease prevention effect and soil enzyme activity were studied,so as to provide a theoretical basis for the application of foliar fertilizers in cotton production. [Methods]Through two years of field experiments,six treatments were set in total,namely spraying water( CK),traditional Bordeaux mixture( BDM),Kocide 2000( KCD),copper-based nutrient foliar fertilizer( CF),iron-copper-based nutrient foliar fertilizer( CFFe),and zinc-boron-copper-based nutrient foliar fertilizer( CFZnB). Randomized block arrangement was adopted. Chlorophyll content in leaves was measured at each growth stage of the cotton. Photosynthetic characteristics of leaves were measured at the peak bolling stage. Plants were sampled at initial boll opening stage. The whole plant was divided into root,stem,leaf and cotton boll parts,in which the total copper,total zinc,total iron contents and accumulations were determined. Soil samples were collected from each plot,followed by the determination of soil enzyme activity. Disease index was investigated at bud,flowering and boll-forming and boll opening stage. [Results]( 1) Spraying CFFe,CFZnB,CF and KCD could significantly improve chlorophyll content of cotton leaves,and the CFFe treatment had the highest increase up to13. 30%,followed by the CFZnB treatment,which was 11. 40% higher than the CK; and photosynthetic rate,stomata conductance and transpiration rate could be improved significantly,and the CFFe treatment showed the highest photosynthetic rate,which increased by 26. 35% compared with the CK,followed by the CFZnB treatment,which increased by 17. 96% compared with CK; and intercellular CO2 concentration was significantly reduced.( 2) Spraying BDM,KCD,CF,CFFe and CFZnB can significantly increase total copper content and accumulation in various cotton organs( except the total copper content in the stem part of the CFZnB treatment; the CFZnB and CFFe treatments can significantly increase total zinc content and accumulation in various cotton organs; and spraying CFFe,CFZnB and CF can significantly increase total iron content and accumulation in various cotton organs( except the total iron content in the stem part of the CF treatment).( 3)Spraying CFFe,CFZnB,CF,KCD and BDM greatly reduced the disease index at flowering and boll-forming and boll opening stages.( 4) The CFZnB and CFFe treatments had the highest soil urease activity,which was 7. 14% higher than that of the CK,but the difference from the CK was not significant; the catalase activity of each treatment was significantly higher than that of the BDM treatment; and the sucrase activity of each treatment was significantly higher than that of the CK.( 5) Spraying CFFe,CFZnB,CF and KCD significantly improved lint yield of cotton,and the CFZnB treatment showed the highest yield increase up to 12. 34%,followed by the CFFe treatment,with an increase in the range of 8. 77%-10. 20%. [Conclusions]Copper-based nutrient foliar fertilizers have dual functions of disease control and prevention and plant nutrition and health care,and not only can significantly increase cotton yield,but also has certain disease prevention effect.It is recommended to use copper-based nutrient foliar fertilizers.展开更多
In Kenya, foliar fertilizers have not found use in tea production despite their numerous advantages as exhibited in other crops. A fertilizer trial test was established in three sites of the major tea growing regions,...In Kenya, foliar fertilizers have not found use in tea production despite their numerous advantages as exhibited in other crops. A fertilizer trial test was established in three sites of the major tea growing regions, with 36 plots per site to determine the effects of foliar fertilizer application on tea quality. Two foliar fertilizers were tested;foliar fertilizer 1 (FF1) and foliar fertilizer 2 (FF2), with a positive control of soil fertilizer (SF) and a blank. Two leaves and a bud tea samples were collected every two weeks after each foliar fertilizer application. These were then analyzed for tea quality (total polyphenols, TP), nutrient residues for the different clones and geographical locations. The TP contents for clone TRFK 31/8 were as follows: FF1 = 17.8%, FF2 = 17.9%, SF = 16.56% and Zero = 17.4%. Tukey-Kramer pair wise comparison test results between the foliar fertilizers and SF showed that the FF1 (HSD = 4.78) and FF2 (HSD = 5.27) fertilizers had significantly (P < 0.05) higher levels of TP content as compared to control SF fertilizer. Nutrients analyzed had average means as follows: N = 4% - 5%, P = 0.25% - 0.28%, K = 1.35% - 1.69%, Ca = 0.3 - 0.5 ppm, Mg = 0.19 - 0.27 ppm, Mn = 0.05 - 0.13 ppm, Zn = 25 - 40.5 ppm, Cu = 11 - 17 ppm and Fe = 72 - 122 ppm. The nutrient residue levels had non-significantly statistical differences at P < 0.05 level between pairs of zero applied plots and the FF1, FF2 and SF applied plots respectively. It was concluded that the foliar fertilizers increased the TP content in tested tea samples and the nutrients analyzed were all within the dietary reference intake (DRI) levels for SF, FF1 and FF2. Overall, the foliar fertilizer increased the quality of the tested tea samples.展开更多
Water is essential for the growth period of crops;however,water unavailability badly affects the growth and physiological attributes of crops,which considerably reduced the yield and yield components in crops.Therefor...Water is essential for the growth period of crops;however,water unavailability badly affects the growth and physiological attributes of crops,which considerably reduced the yield and yield components in crops.Therefore,a pot experiment was conducted to investigate the effect of foliar phosphorus(P)on morphological,gas exchange,biochemical traits,and phosphorus use efficiency(PUE)of maize(Zea mays L.)hybrids grown under normal as well as water deficit situations at the Department of Agronomy,University of Agriculture Faisalabad,Pakistan in 2014.Two different treatments(control and P@8 kg ha^(−1))and four hybrids(Hycorn,31P41,65625,and 32B33)of maize were tested by using a randomized complete block design(RCBD)with three replications.Results showed that the water stress caused a remarkable decline in total soluble protein(9.7%),photosynthetic rate(9.4%)and transpiration rate(13.4%),stomatal conductance(10.2%),and internal CO_(2)rate(20.4%)comparative to well-watered control.An increase of 37.1%,36.8%,and 24.5%were recorded for proline,total soluble sugar,and total free amino acid,respectively.However,foliar P application minimized the negative impact of drought by improving plant growth,physio-biochemical attributes,and PUE in maize plants under water stress conditions.Among the hybrids tested,the hybrid 6525 performed better both under stress and non-stress conditions.These outcomes confirmed that the exogenous application of P improved drought stress tolerance by modulating growth,physio-biochemical attributes,and PUE of maize hybrids.展开更多
Anand, the milk capital of India, is a developing city with increasing vehicles and developmental activities going on at a fast pace. This study attempts to investigate the zinc and chromium concentration in street du...Anand, the milk capital of India, is a developing city with increasing vehicles and developmental activities going on at a fast pace. This study attempts to investigate the zinc and chromium concentration in street dust, suspended particulate matter and in foliar dust deposits. Ten sampling locations were selected based on the traffic density on the roads and different anthropogenic activity. Sampling was carried out in the dry months of January to March 2011. The range of Zn and Cr was 16.82 - 108.29 ppm and 118 - 151.5 ppm in the street dust respectively. Zn concentration in Suspended particulate matter lies in the range of 12.41 to 86 ppm and Cr concentration between 75 to 130 ppm. The range of Cr in foliar deposited dust varied from 79.54 ppm to 31 ppm. Whereas, for Zn maximum concentration was in S10 which is 42.34 ppm and minimum was in site S9, 23.73 ppm. ANOVA single factor showed that at 0.05 level of significance site wise variation of zinc and chromium concentration in SPM, Street dust and foliar deposited dust was not significant signifying similar source of contamination. Which is further strengthened by the good positive correlation found between the Zn and Cr concentration of street dust, leaf deposited dust and SPM. The Contamination Factor in the sites where metal concentration was high was 1.24 in S10 and 1.06 in S5 for Zn. For chromium the value of CF was 1.77 in S10 and 1.67 in S5. These values indicate that street dust is moderately contaminated with respect to zinc and chromium.展开更多
Glimpses of unusual climatic conditions such as high summer temperature, heavy rainfall as well as snowfall and low winter temperature were noticed during 2010-2011 in subalpine-timberline (2700 - 3600 m) zones of Wes...Glimpses of unusual climatic conditions such as high summer temperature, heavy rainfall as well as snowfall and low winter temperature were noticed during 2010-2011 in subalpine-timberline (2700 - 3600 m) zones of Western Himalaya. Abundant winter injury to the current year (2010) foliage and shoot of Rhododendron arboretum and Quercus semecarpifolia became apparent in winters of 2010-2011. The foliar and bud mortality both increased with elevation beyond 2800 m and maximum along the edges of forest. Rhododendron campanulatum was another species which also got affected throughout the Western Himalaya. Such events were not reported earlier from the region and current observations indicate the high sensitivity of the plant species to the extreme inter-annual climatic variations.展开更多
Nitrogen is a major nutrient involved in plant growth and yield. Plants cannot get the nutrients from the soil medium under water stress condition to testify foliar application in stress condition to fulfil plant need...Nitrogen is a major nutrient involved in plant growth and yield. Plants cannot get the nutrients from the soil medium under water stress condition to testify foliar application in stress condition to fulfil plant need for better performance. In this regard, a field study was conducted to evaluate the effect of foliar-applied nitrogen (0, water and 1% urea) on sunflower (cv. Hysun-33) under normal and water stress at reproductive stage. Two soil applied nitrogen levels control (0 kg·ha-1) and recommended dose (115 kg·ha-1). Supplemental foliar application of nitrogen in the form of urea significantly increased the growth, yield and yield components of sunflower under water stress. The increase in yield with 1% urea spray was recorded up to 1.37 t·ha-1 in comparison to water spray (1.07 t·ha-1) and no spray (1.00 t·ha-1). While maximum values of all factors were obtained where 1% urea spray with soil applied nitrogen was used in both stresses as well as in non-stress condition. Therefore, reasonable yield can be achieved by applying foliar application of urea (1%) as a supplemental source to soil applied nitrogen under water stress.展开更多
[Objectives]This study was conducted to explore the treatment methods of amino acid selenium fertilizer suitable for increasing the selenium content of mangoes and improving the quality of mangoes,so as to provide a t...[Objectives]This study was conducted to explore the treatment methods of amino acid selenium fertilizer suitable for increasing the selenium content of mangoes and improving the quality of mangoes,so as to provide a theoretical basis for the production of selenium-enriched mangoes.[Methods]With Tainong mango as a test material,the amino acid selenium foliar fertilizer was applied by eight treatment methods to investigate the changes of selenium,soluble solid,vitamin C,and titratable acid contents in mango flesh and peel.[Results]Spraying amino acid selenium foliar fertilizer increased the selenium content of mango flesh.The selenium contents of the treatment groups T2,T3,T4 and T5 reached the selenium-enriched standard,and the T2 treatment group had the highest selenium content(0.020 mg/kg).The selenium contents in the peel of all treatment groups were greater than the corresponding selenium content in the flesh.Except for T1,the vitamin C contents of other treatment groups sprayed with amino acid selenium fertilizer increased compared with the control,and that of the T2 treatment group increased significantly(P<0.05).Compared with the control,the soluble solids of the treatment groups sprayed with amino acid selenium fertilizer once also increased.The treatment method of spraying amino acid selenium fertilizer with a dosage of 12000 ml/hm2 once(T2)achieved the best effect of increasing the selenium content and improving the quality of mangoes.[Conclusions]This study provides a scientific basis for increasing the selenium content of mangoes and improving the current situation of insufficient selenium intake.展开更多
Khaya belongs to the family Meliaceae. In Nigeria the genus is represented by three species viz; K. senegalensis A. Juss.,K. grandifoliola C. DC. and K. ivorensis A. Chev. Comparative foliar anatomy of the three Khaya...Khaya belongs to the family Meliaceae. In Nigeria the genus is represented by three species viz; K. senegalensis A. Juss.,K. grandifoliola C. DC. and K. ivorensis A. Chev. Comparative foliar anatomy of the three Khaya species was carried out to identify and describe distinctive anatomical characters that could possibly be used to delimit the three taxa. Transverse section, epidermal peels and cleared leaves of these three species were made. Characteristic similarity and disparity in the tissues arrangement as well as cell inclusions were noted for description and delimitation. The three Khaya species studied had essentially the same anatomical features, e.g., venation pattern having open polygonal areoles and the veins terminals biforkated. However, there were characters that seem to be species specific, e.g., vien termination number and areole width. The leaf epidermal studies of the three species revealed similarities in stomatal type which are generally staurocytic,epidermal cells and undulating anticlinal cell walls but stomata density varied. Hexacytic stomata is only observed in the abaxial surface of K. grandifoliola which distinguished this species from the others. The leaf petiole shape of the three species are round and difficult to distinguish into adaxial and abaxial surfaces. The cuticle is striated, vascular bundles are heart shape, conjoint, concentric and amphivasal, but are different in epidermal and collenchyma cell layer numbers. The leaf transverse sections of the three Khaya species studied have conjoint, concentric and amphicribral bundles while the leaf cuticle of K. senegalensis and K. grandifoliola are striated but that of Khaya ivorensis is non-striated.展开更多
Water was a key factor restricting the plantation in sandy areas. Foliar δ^(13)C value regarded as an indicator of longterm water use efficiency(WUE) of plants was generally used to evaluate the adaptability of plant...Water was a key factor restricting the plantation in sandy areas. Foliar δ^(13)C value regarded as an indicator of longterm water use efficiency(WUE) of plants was generally used to evaluate the adaptability of plants to arid and semi-arid environment. In Horqin sandy land of China, the foliar δ^(13)C values of 114 species in 35 families naturally growing in the area, and 15 species of sand-fixing trees and shrubs were measured and analyzed in 2012. The results showed that 97 species in all 114 species were C_3 plants and only 17 species were C_4 plants. Most C_4 plants belonged to Gramineae family. The foliar δ^(13)C value of C_3 plants was between -25.000 and -31.075‰ with an average of-28.226‰, while those of C_4 plants between -12.578 and -16.334‰, with an average of -13.678‰. The δ^(13)C values of mature leaves collected in August were averagely 0.85‰ less than that of juvenile leaves collected in June. The foliar δ^(13)C values and WUE of 15 sand-fixing tree species in Horqin sandy land ranked in the order as: S.vulgaris >H.rhamnoides >C.ovata >P.mongolica >T.chinensis >R.typhina >S.matsudana >E.angustifolia >U.pumila >S.gordejevii >X.sorbifolia >C.microphylla >H.fruticosum >C.korshinskii >E.bungeanus.展开更多
Grain zinc(Zn) and iron(Fe) concentrations and their responses to foliar application of micronutrients in 28 Chinese wheat landraces and 63 cultivars were investigated in a two-year field experiment. The average grain...Grain zinc(Zn) and iron(Fe) concentrations and their responses to foliar application of micronutrients in 28 Chinese wheat landraces and 63 cultivars were investigated in a two-year field experiment. The average grain Zn and Fe concentrations were 41.8 mg kg^(-1)(29.0-63.3 mg kg^(-1)) and 39.7 mg kg^(-1)(27.9-67.0 mg kg^(-1)), respectively. Compared with cultivars, landraces had greater grain Zn(11.0%) and Fe(4.8%) concentrations but lower harvest index(HI), grain weight per spike(GWS), grain number per spike(GNS) and thousand grain weight(TGW). Both Zn and Fe concentrations were negatively and significantly correlated with HI, GWS, and GNS, while showed a poor association with TGW, suggesting that lower HI, GWS, and GNS, but not TGW, accounted for higher Zn and Fe concentrations for landraces than for cultivars. Grain Zn concentrations of both cultivars and landraces significantly increased after foliar Zn spray and the increase was two-fold greater for landraces(12.6 mg kg^(-1)) than for cultivars(6.4 mg kg^(-1)). Foliar Fe spray increased grain Fe concentrations of landraces(3.4 mg kg^(-1)) and cultivars(1.2 mg kg^(-1)), but these increases were not statistically significant. This study showed that Chinese wheat landraces had higher grain Zn and Fe concentrations than cultivars, and greater increases occurred in grain Zn concentration than in grain Fe concentration in response to fertilization, suggesting that Chinese wheat landraces could serve as a potential genetic source for enhancing grain mineral levels in modern wheat cultivars.展开更多
Bt cotton hybrids require large supply of metabolites to support their greater boll load and commonly suffer from premature leaf senescence. A field experiment was conducted to study the nutritional status of Bt cotto...Bt cotton hybrids require large supply of metabolites to support their greater boll load and commonly suffer from premature leaf senescence. A field experiment was conducted to study the nutritional status of Bt cotton leaves during boll development stage and to evaluate the most profitable source of foliar fertilizers. Treatments included basal application of 0 and 60 kg·K2O·ha-1 as muriate of potash (MOP) in main plots and foliar spray treatments viz: 4 & 6 sprays of 2% potassium nitrate (Multi-K, 13-00-45), 4 & 6 sprays of NPK Blend (Polyfed, 19-19-19), 4 sprays of MOP, 4 sprays of MOP + urea (to supply same amount of N & K as in potassium nitrate) and unsprayed control in sub plots. The results revealed that only N and K contents of premature senesced leaves were below the sufficiency range for cotton sufficient levels of P, Fe, Mn, Zn and Cu were observed. Though the concentrations of N and K in both the petiole and leaf blade initially improved with foliar spray, N content declined below the unsprayed control at later stages. Basal application of MOP increased seed cotton yield by 19%. Four foliar sprays of KNO3, NPK, MOP and MOP + urea recorded yield increase in seed cotton yield of 22.8%, 22.4%, 18.5% and 24.5%, respectively over unsprayed control. Six sprays of KNO3 and NPK had no yield advantage over four sprays and rather proved economically less viable.展开更多
The objective of this research was to evaluate the effectiveness of soil and foliar application of potassium (K) on leaf and seed mineral concentration levels, and seed composition (protein, oil, fatty acids, and mine...The objective of this research was to evaluate the effectiveness of soil and foliar application of potassium (K) on leaf and seed mineral concentration levels, and seed composition (protein, oil, fatty acids, and minerals). Soybean cultivar (Pioneer 95470) of maturity group 5.7 was grown in a repeated greenhouse experiment in a randomized complete block design. Treatment consisted of two concentrations of foliar K application (T1, rate of 1.75% and T2, rate of 2.5%) and soil application (T3, rate of 190 mg/kg and T4, rate of 380 mg/kg). Potassium was applied for each type at V3 (vegetative) and R3 (beginning of seed pod initiation) stages. The results showed higher K and S concentrations in leaves in T1 and T2. The concentrations of B and Zn decreased in all treatments, whereas Fe concentration increased in T1 and T3. In seeds, most mineral concentrations were stable, except for Fe which increased in both T1 and T3. Seed protein percentage increased 3.0% in T3 compared with the control (no K application). Seed oil percentage showed a general decrease in all the treatments, except for 3.2% increase in T4. Palmitic acid percentages showed significant increase in all concentrations, the highest percentage increase of 16.9% was observed in T4. Stearic acid increased in T2 and T3. Linoleic acid percentages increased in both foliar treatments, but linolenic acid percentage increased in high soil treatment T4 alone, with an increase of 12.2% in comparison to the control. Significant decrease (15.8%) in linoleic acid was found in foliar application, T2. Oleic acid decreased uniformly in all treatments, where the highest decrease (19.2%) was observed in soil application, T4. Our research demonstrated that both foliar and soil application of K were found to selectively alter seed composition. Further research is needed to be conducted under field conditions before conclusions can be made.展开更多
基金supported by the National Natural Science Foundation of China(Grant No.31971843)the Technology System of Modern Agricultural Industry in Guangdong Province,China(Grant No.2020KJ105)+1 种基金the Guangzhou Science and Technology Project,Guangdong Province,China(Grant No.202103000075)the Special Rural Revitalization Funds of Guangdong Province,China(Grant No.2021KJ382)。
文摘Applying iodine fertilizers to cultivate iodine-rich crops for daily intake is an effective approach for iodine supplementation,especially for aromatic rice.Field experiments were conducted during the early growing seasons of 2021 and 2022 to evaluate the impacts of foliar application of iodine fertilizer on aromatic rice and to explore the optimal iodine fertilizer concentration.At the full heading stage,six different concentrations of sodium iodide solutions of 0%(CK),0.010%(T1),0.025%(T2),0.050%(T3),0.075%(T4),and 0.100%(T5)were applied to indica aromatic rice cultivars Meixiangzhan 2 and Xiangyaxiangzhan.The results showed that sodium iodide treatments significantly increased the iodine and sodium contents in both leaves and grains.Compared with the CK,the T1 and T2 treatments increased the 2-acetyl-1-pyrroline(2-AP)content in mature grains by 8.41%-101.66%and 13.58%-74.60%,respectively.Improvements in the contents of 1-pyrroline-5-carboxylic acid,proline,1-pyrroline,and methylglyoxal,as well as the activity of proline dehydrogenase were also detected.Additionally,sodium iodide treatments remarkably decreased the chalky grain rate,chalkiness area,and chalkiness degree of aromatic rice,with the T2 treatment exhibiting a 17.79%-47.42%decrease in chalkiness degree compared with the CK.Meanwhile,T1 and T2 treatments showed beneficial impacts on chlorophyll content,photosynthetic characteristics,and yield components,while T3,T4,and T5 treatments exhibited adverse effects on leaf and grain yields.The linear discriminant analysis revealed significant differences between treatments.The correlation analysis and piecewise structural equation modeling showed that the iodine and sodium influenced the photosynthetic characteristics and chlorophyll content of the leaves,thereby regulating the 2-AP biosynthesis and yield components,ultimately affecting the 2-AP content and yield.Overall,this study suggests that foliar application of 0.025%sodium iodide is an effective method to enrich the iodine content in rice grains,improve the grain aroma and appearance quality of aromatic rice,without detrimental effects on grain yield.
基金supported by the National Natural Science Foundation of China(Grant Number 31370628)the National Science and Technology Support Project of China(Grant Number2011BAC09B05)the Sichuan Provincial Science and Technology Support Project(Grant Number 12ZC0017)
文摘Forest gaps are important in forest dynamics and management, but little is known about how soil fauna influence the degradation of recalcitrant litter components in different-sized forest gaps. This investigation uses litterbags with two different mesh sizes (0.04 and 3 mm) to control the meso- and microfauna entering the bags to quantify the contribution of soil fauna to the degradation of recalcitrant components (including condensed tannins, total phenol, lignin and cellulose) during litter decomposition. The experiment was conducted in seven different forest gap sizes in Pinus massoniana plantations over 1 year. One closed-canopy site (CC) and forest gap sizes of 100, 225, 400, 625, 900, 1225 and 1600 m^2 were created in a P. massoniana plantation in the Sichuan basin of China;the CC was treated as the control. Cinnamomum camphora foliage from local native trees was used in all forest gap experiments. We found the following:(1) Gap size had significant effects on the degradation rates (E) of condensed tannins and lignin and on the contributions of soil fauna;medium-sized gaps also presented high degradation rates. Soil fauna obviously contributed to the degradation of recalcitrant foliar litter components in medium-sized gaps.(2) The highest contribution to degradation (40.98%) was recorded for lignin, and the lowest contribution (0.29%) was recorded for condensed tannins. The results indicate that medium-sized gaps (900 m^2) were conducive to the degradation of recalcitrant litter components by soil fauna.
基金supported by the Italian Ministry for Agricultural and Forest Policy,under the programme Ri.Selv.Italia(Research unit 3.2.1,DIBAF,University of Viterbo)
文摘We estimated water-use efficiency and potential photosyn- thetic assimilation of Holm oak (Quercus ilex L.) on slopes of NW and SW aspects in a replicated field test examining the effects of intensifying drought in two Mediterranean coppice forests. We used standard tech- niques for quantifying gas exchange and carbon isotopes in leaves and analyzed total chlorophyll, carotenoids and nitrogen in leaves collected from Mediterranean forests managed under the coppice system. We pos- tulated that responses to drought of coppiced trees would lead to differ- ential responses in physiological traits and that these traits could be used by foresters to adapt to predicted warming and drying in the Mediterra- nean area. We observed physiological responses of the eoppiced trees that suggested acclimation in photosynthetic potential and water-use effi- ciency: (1) a significant reduction in stomatal conductance (p〈0.01) wasrecorded as the drought increased at the SW site; (2) foliar 813C increased as drought increased at the SW site (p〈0.01); (3) variations in levels of carotenoids and foliar nitrogen, and differences in foliar morphology were recorded, and were tentatively attributed to variation in photosyn- thetic assimilation between sites. These findings increase knowledge of the capacity for acclimation of managed forests in the Mediterranean region of Europe.
基金funded by the National Key Research and Development Program of China (2017YFD0200106)
文摘In order to completely evaluate ammonia emission from greenhouse vegetable fields,crop canopy absorption should not be neglected.The foliar uptake of NH3 applied at two growth stages and the subsequent 15N-labeled N translocation to other plant components were investigated under greenhouse conditions using chambers covered with the soil of a tomato field.Treatments comprised three NH3-N application rates(70,140,and 210 mg/plot) using 15N-labeled ammonium sulfate.Plants were harvested immediately after exposure for 24 h,and the total N concentrations and 15N/14 N ratios were determined.With increased NH3 concentration,total 15NH3-N absorption increased considerably,whereas the applied 15NH3-N uptake decreased gradually.The tomato plants absorbed 33-38% and 24-31% of the 15NH3-N generated at the anthesis and fruit growth stages,respectively.A total of 71-80% of the recovered NH3 was observed in the leaves and 20-30% of the recovered NH3 was remobilized to other components.Among them,an average of 10% of the absorbed 15NH3-N was transferred into the tomato fruits.All these results indicated the potential of the tested tomatoes for the foliar uptake of atmospheric 15NH3 and the distribution of 15N-labeled vegetative N among different plant components.The results are of great importance for the complete evaluation of nitrogen use efficiency in the greenhouse tomato fields.
基金the National Key Research and Development Program of China(2018YFD0300707 and 2016YFD0300400)the Modern Wheat Industrial Technology System of Henan Province,China(S2010-01-G07).
文摘Increasing zinc(Zn)concentration in wheat grain is important to minimize human dietary Zn deficiency.This study aimed to investigate the effect of foliar Zn and soil nitrogen(N)applications on the accumulation and distribution of N and Zn in grain pearling fractions,N remobilization,and the relationships between nutrient concentration in the vegetative tissues and grain or its fractions in two cropping years in the North China Plain.The results showed a progressive decrease in N and Zn concentrations from the outer to the inner parts of grain,with most of the accumulation in the core endosperm.Foliar Zn application significantly increased N concentration in the pericarp,and soil N application increased N concentration in each grain fraction.Both treatments significantly increased core endosperm Zn concentration.Foliar Zn had no effect on grain N and Zn distribution.Soil N application made N concentrated in the aleurone,promoted Zn translocation to the core endosperm and also increased N remobilization and its efficiency from the shoot to the grain,but no improved contribution to grain was found.N concentration in grain and its fractions were positively correlated with N in vegetative organs at anthesis and maturity,while positive correlations were obtained between N concentration in the pericarp and progressive central area of the endosperm and Zn concentration in the core endosperm.Thus,foliar Zn and soil N applications effectively increased yield and N and Zn concentrations in the wheat grain,particularly in the endosperm,and could be promising strategies to address Zn deficiency.
基金financially supported by the National Natural Science Foundation of China (U1203283, 31260295)the Special Launching Funds for High-Level Talents of Shihezi University, China (RCZX201005)the Australian Research Council (DP1093827)
文摘Water deficit is one of the most important causes of decreased yield in cultivated plants. Non-foliar green organs in cotton play an important role in yield formation at the late growth stage. Although better photosynthetic performance was observed in a non-foliar organ (bract) compared with leaves under water deficit. However, the physiological response of each organ in cotton to water deficit has not been comprehensively studied in relation to the water status and photosynthesis characteristics. We studied the maintenance of water status of each organ in cotton by measuring their relative water content, proline content and stomatal characteristics. Water deficit significantly decreased the surface area of each organ, but to a lesser extent in non-foliar organs. Our results showed that the relative contribution of biomass accumulation of non-foliar organs increased under water deficit. Non-foliar organs (bracts and capsule wall) showed less ontogenetic decrease in O2 evolution capacity and in RuBPC activity (per dry weight) as well as better antioxidant systems than leaves at various days after anthesis. We conclude that the photosynthesis from non-foliar organs is important for increasing cotton yield especially under water deficit conditions.
基金supported by the University Grants Commission Rajiv Gandhi National Fellowship(RGNF) of India
文摘A field study was undertaken to ascertain the effects of elicitors viz. benzothiadiazole (BTH) and salicylic acid (SA) on defense related enzymes viz. peroxidase, phenylalanine ammonia lyase, superoxide dismutase, chitinase and 13-1,3-glucanase, and phenols in rice (Pusa Basmati I) plants. First foliar spray of BTH (50 mg/kg) and SA (50 mg/kg) was done at the maximum tillering stage and inoculation with Rhizoctonia solani was carried 24 h after elicitor treatment. Elicitors were further sprayed at every growth stage. Time course analysis showed peak accumulation of defense related enzymes and phenols in the rice leaves treated with BTH and SA, and accumulation was the highest at the flowering stage. Higher enzymatic activity was observed in elicitor treated plants inoculated with R. solani. Compared to the untreated control plants, application of elicitors before R. solani inoculation significantly elicited the defense related enzymes and phenols. Moreover, application of elicitors had a positive effect on yield and disease reduction. It is suggested that pretreatment of rice leaves with BTH and SA could be used to enhance the level of protection against sheath blight and to improve rice yield in the fields.
基金sponsored by Department of Agriculture and Co-operation and Farmer Welfare(DAC&FW),Ministry of Agriculture,Government of India and Mars Wrigley,USAthe award of Junior/Senior Research Fellowship from Department of Biotechnology,Government of Indiapart of the CGIAR Research Program on Grain Legumes and Dryland Cereals(GLDC)
文摘Foliar fungal diseases(rust and late leaf spot)incur large yield losses,in addition to the deterioration of fodder quality in groundnut worldwide.High oleic acid has emerged as a key market trait in groundnut,as it increases the shelf life of the produce/products in addition to providing health benefits to consumers.Marker-assisted backcrossing(MABC)is the most successful approach to introgressing or pyramiding one or more traits using traitlinked markers.We used MABC to improve three popular Indian cultivars(GJG 9,GG 20,and GJGHPS 1)for foliar disease resistance(FDR)and high oleic acid content.A total of 22 BC3F4 and 30 BC2F4 introgression lines(ILs)for FDR and 46 BC3F4 and 41 BC2F4 ILs for high oleic acid were developed.Recurrent parent genome analysis using the 58 K Axiom_Arachis array identified several lines showing upto 94%of genome recovery among second and third backcross progenies.Phenotyping of these ILs revealed FDR scores comparable to the resistant parent,GPBD 4,and ILs with high(~80%)oleic acid in addition to high genome recovery.These ILs provide further opportunities for pyramiding FDR and high oleic acid in all three genetic backgrounds as well as for conducting multi-location yield trials for further evaluation and release for cultivation in target regions of India.
文摘[Objectives] The effects of copper-based nutrient foliar fertilizer on photosynthetic characteristics,yield,accumulation and distribution of trace elements in various organs,disease prevention effect and soil enzyme activity were studied,so as to provide a theoretical basis for the application of foliar fertilizers in cotton production. [Methods]Through two years of field experiments,six treatments were set in total,namely spraying water( CK),traditional Bordeaux mixture( BDM),Kocide 2000( KCD),copper-based nutrient foliar fertilizer( CF),iron-copper-based nutrient foliar fertilizer( CFFe),and zinc-boron-copper-based nutrient foliar fertilizer( CFZnB). Randomized block arrangement was adopted. Chlorophyll content in leaves was measured at each growth stage of the cotton. Photosynthetic characteristics of leaves were measured at the peak bolling stage. Plants were sampled at initial boll opening stage. The whole plant was divided into root,stem,leaf and cotton boll parts,in which the total copper,total zinc,total iron contents and accumulations were determined. Soil samples were collected from each plot,followed by the determination of soil enzyme activity. Disease index was investigated at bud,flowering and boll-forming and boll opening stage. [Results]( 1) Spraying CFFe,CFZnB,CF and KCD could significantly improve chlorophyll content of cotton leaves,and the CFFe treatment had the highest increase up to13. 30%,followed by the CFZnB treatment,which was 11. 40% higher than the CK; and photosynthetic rate,stomata conductance and transpiration rate could be improved significantly,and the CFFe treatment showed the highest photosynthetic rate,which increased by 26. 35% compared with the CK,followed by the CFZnB treatment,which increased by 17. 96% compared with CK; and intercellular CO2 concentration was significantly reduced.( 2) Spraying BDM,KCD,CF,CFFe and CFZnB can significantly increase total copper content and accumulation in various cotton organs( except the total copper content in the stem part of the CFZnB treatment; the CFZnB and CFFe treatments can significantly increase total zinc content and accumulation in various cotton organs; and spraying CFFe,CFZnB and CF can significantly increase total iron content and accumulation in various cotton organs( except the total iron content in the stem part of the CF treatment).( 3)Spraying CFFe,CFZnB,CF,KCD and BDM greatly reduced the disease index at flowering and boll-forming and boll opening stages.( 4) The CFZnB and CFFe treatments had the highest soil urease activity,which was 7. 14% higher than that of the CK,but the difference from the CK was not significant; the catalase activity of each treatment was significantly higher than that of the BDM treatment; and the sucrase activity of each treatment was significantly higher than that of the CK.( 5) Spraying CFFe,CFZnB,CF and KCD significantly improved lint yield of cotton,and the CFZnB treatment showed the highest yield increase up to 12. 34%,followed by the CFFe treatment,with an increase in the range of 8. 77%-10. 20%. [Conclusions]Copper-based nutrient foliar fertilizers have dual functions of disease control and prevention and plant nutrition and health care,and not only can significantly increase cotton yield,but also has certain disease prevention effect.It is recommended to use copper-based nutrient foliar fertilizers.
文摘In Kenya, foliar fertilizers have not found use in tea production despite their numerous advantages as exhibited in other crops. A fertilizer trial test was established in three sites of the major tea growing regions, with 36 plots per site to determine the effects of foliar fertilizer application on tea quality. Two foliar fertilizers were tested;foliar fertilizer 1 (FF1) and foliar fertilizer 2 (FF2), with a positive control of soil fertilizer (SF) and a blank. Two leaves and a bud tea samples were collected every two weeks after each foliar fertilizer application. These were then analyzed for tea quality (total polyphenols, TP), nutrient residues for the different clones and geographical locations. The TP contents for clone TRFK 31/8 were as follows: FF1 = 17.8%, FF2 = 17.9%, SF = 16.56% and Zero = 17.4%. Tukey-Kramer pair wise comparison test results between the foliar fertilizers and SF showed that the FF1 (HSD = 4.78) and FF2 (HSD = 5.27) fertilizers had significantly (P < 0.05) higher levels of TP content as compared to control SF fertilizer. Nutrients analyzed had average means as follows: N = 4% - 5%, P = 0.25% - 0.28%, K = 1.35% - 1.69%, Ca = 0.3 - 0.5 ppm, Mg = 0.19 - 0.27 ppm, Mn = 0.05 - 0.13 ppm, Zn = 25 - 40.5 ppm, Cu = 11 - 17 ppm and Fe = 72 - 122 ppm. The nutrient residue levels had non-significantly statistical differences at P < 0.05 level between pairs of zero applied plots and the FF1, FF2 and SF applied plots respectively. It was concluded that the foliar fertilizers increased the TP content in tested tea samples and the nutrients analyzed were all within the dietary reference intake (DRI) levels for SF, FF1 and FF2. Overall, the foliar fertilizer increased the quality of the tested tea samples.
文摘Water is essential for the growth period of crops;however,water unavailability badly affects the growth and physiological attributes of crops,which considerably reduced the yield and yield components in crops.Therefore,a pot experiment was conducted to investigate the effect of foliar phosphorus(P)on morphological,gas exchange,biochemical traits,and phosphorus use efficiency(PUE)of maize(Zea mays L.)hybrids grown under normal as well as water deficit situations at the Department of Agronomy,University of Agriculture Faisalabad,Pakistan in 2014.Two different treatments(control and P@8 kg ha^(−1))and four hybrids(Hycorn,31P41,65625,and 32B33)of maize were tested by using a randomized complete block design(RCBD)with three replications.Results showed that the water stress caused a remarkable decline in total soluble protein(9.7%),photosynthetic rate(9.4%)and transpiration rate(13.4%),stomatal conductance(10.2%),and internal CO_(2)rate(20.4%)comparative to well-watered control.An increase of 37.1%,36.8%,and 24.5%were recorded for proline,total soluble sugar,and total free amino acid,respectively.However,foliar P application minimized the negative impact of drought by improving plant growth,physio-biochemical attributes,and PUE in maize plants under water stress conditions.Among the hybrids tested,the hybrid 6525 performed better both under stress and non-stress conditions.These outcomes confirmed that the exogenous application of P improved drought stress tolerance by modulating growth,physio-biochemical attributes,and PUE of maize hybrids.
文摘Anand, the milk capital of India, is a developing city with increasing vehicles and developmental activities going on at a fast pace. This study attempts to investigate the zinc and chromium concentration in street dust, suspended particulate matter and in foliar dust deposits. Ten sampling locations were selected based on the traffic density on the roads and different anthropogenic activity. Sampling was carried out in the dry months of January to March 2011. The range of Zn and Cr was 16.82 - 108.29 ppm and 118 - 151.5 ppm in the street dust respectively. Zn concentration in Suspended particulate matter lies in the range of 12.41 to 86 ppm and Cr concentration between 75 to 130 ppm. The range of Cr in foliar deposited dust varied from 79.54 ppm to 31 ppm. Whereas, for Zn maximum concentration was in S10 which is 42.34 ppm and minimum was in site S9, 23.73 ppm. ANOVA single factor showed that at 0.05 level of significance site wise variation of zinc and chromium concentration in SPM, Street dust and foliar deposited dust was not significant signifying similar source of contamination. Which is further strengthened by the good positive correlation found between the Zn and Cr concentration of street dust, leaf deposited dust and SPM. The Contamination Factor in the sites where metal concentration was high was 1.24 in S10 and 1.06 in S5 for Zn. For chromium the value of CF was 1.77 in S10 and 1.67 in S5. These values indicate that street dust is moderately contaminated with respect to zinc and chromium.
文摘Glimpses of unusual climatic conditions such as high summer temperature, heavy rainfall as well as snowfall and low winter temperature were noticed during 2010-2011 in subalpine-timberline (2700 - 3600 m) zones of Western Himalaya. Abundant winter injury to the current year (2010) foliage and shoot of Rhododendron arboretum and Quercus semecarpifolia became apparent in winters of 2010-2011. The foliar and bud mortality both increased with elevation beyond 2800 m and maximum along the edges of forest. Rhododendron campanulatum was another species which also got affected throughout the Western Himalaya. Such events were not reported earlier from the region and current observations indicate the high sensitivity of the plant species to the extreme inter-annual climatic variations.
文摘Nitrogen is a major nutrient involved in plant growth and yield. Plants cannot get the nutrients from the soil medium under water stress condition to testify foliar application in stress condition to fulfil plant need for better performance. In this regard, a field study was conducted to evaluate the effect of foliar-applied nitrogen (0, water and 1% urea) on sunflower (cv. Hysun-33) under normal and water stress at reproductive stage. Two soil applied nitrogen levels control (0 kg·ha-1) and recommended dose (115 kg·ha-1). Supplemental foliar application of nitrogen in the form of urea significantly increased the growth, yield and yield components of sunflower under water stress. The increase in yield with 1% urea spray was recorded up to 1.37 t·ha-1 in comparison to water spray (1.07 t·ha-1) and no spray (1.00 t·ha-1). While maximum values of all factors were obtained where 1% urea spray with soil applied nitrogen was used in both stresses as well as in non-stress condition. Therefore, reasonable yield can be achieved by applying foliar application of urea (1%) as a supplemental source to soil applied nitrogen under water stress.
基金Guangxi Science and Technology Major Project(GK AA17202037-2,GK AA17202026)Guangxi Mango Innovation Team Cultivation Post Project of National Modern Agriculture Industrial Technology System(nycytxgxcxtd-06-02)+4 种基金Special Fund of Central Government for Local Science and Technology Development(GK ZY19183007)Special Action of the Science and Technology Vanguard of Guangxi Academy of Agricultural Sciences(GNK JZ202016)Guangxi Key R&D Program(GK AB16380164)Guangxi Selenium-enriched Crop Experiment Station(GTS2016011)Fundamental Scientific Research Fund of Guangxi Academy of Agricultural Sciences(GNK 2020YM109)。
文摘[Objectives]This study was conducted to explore the treatment methods of amino acid selenium fertilizer suitable for increasing the selenium content of mangoes and improving the quality of mangoes,so as to provide a theoretical basis for the production of selenium-enriched mangoes.[Methods]With Tainong mango as a test material,the amino acid selenium foliar fertilizer was applied by eight treatment methods to investigate the changes of selenium,soluble solid,vitamin C,and titratable acid contents in mango flesh and peel.[Results]Spraying amino acid selenium foliar fertilizer increased the selenium content of mango flesh.The selenium contents of the treatment groups T2,T3,T4 and T5 reached the selenium-enriched standard,and the T2 treatment group had the highest selenium content(0.020 mg/kg).The selenium contents in the peel of all treatment groups were greater than the corresponding selenium content in the flesh.Except for T1,the vitamin C contents of other treatment groups sprayed with amino acid selenium fertilizer increased compared with the control,and that of the T2 treatment group increased significantly(P<0.05).Compared with the control,the soluble solids of the treatment groups sprayed with amino acid selenium fertilizer once also increased.The treatment method of spraying amino acid selenium fertilizer with a dosage of 12000 ml/hm2 once(T2)achieved the best effect of increasing the selenium content and improving the quality of mangoes.[Conclusions]This study provides a scientific basis for increasing the selenium content of mangoes and improving the current situation of insufficient selenium intake.
文摘Khaya belongs to the family Meliaceae. In Nigeria the genus is represented by three species viz; K. senegalensis A. Juss.,K. grandifoliola C. DC. and K. ivorensis A. Chev. Comparative foliar anatomy of the three Khaya species was carried out to identify and describe distinctive anatomical characters that could possibly be used to delimit the three taxa. Transverse section, epidermal peels and cleared leaves of these three species were made. Characteristic similarity and disparity in the tissues arrangement as well as cell inclusions were noted for description and delimitation. The three Khaya species studied had essentially the same anatomical features, e.g., venation pattern having open polygonal areoles and the veins terminals biforkated. However, there were characters that seem to be species specific, e.g., vien termination number and areole width. The leaf epidermal studies of the three species revealed similarities in stomatal type which are generally staurocytic,epidermal cells and undulating anticlinal cell walls but stomata density varied. Hexacytic stomata is only observed in the abaxial surface of K. grandifoliola which distinguished this species from the others. The leaf petiole shape of the three species are round and difficult to distinguish into adaxial and abaxial surfaces. The cuticle is striated, vascular bundles are heart shape, conjoint, concentric and amphivasal, but are different in epidermal and collenchyma cell layer numbers. The leaf transverse sections of the three Khaya species studied have conjoint, concentric and amphicribral bundles while the leaf cuticle of K. senegalensis and K. grandifoliola are striated but that of Khaya ivorensis is non-striated.
基金Supported by the Scientific Research Project of Hebei Higher Education(QN2015306)National Key Technology Research and Development Program of China during the 12th Five-Year Plan(2012BAD16B0302)
文摘Water was a key factor restricting the plantation in sandy areas. Foliar δ^(13)C value regarded as an indicator of longterm water use efficiency(WUE) of plants was generally used to evaluate the adaptability of plants to arid and semi-arid environment. In Horqin sandy land of China, the foliar δ^(13)C values of 114 species in 35 families naturally growing in the area, and 15 species of sand-fixing trees and shrubs were measured and analyzed in 2012. The results showed that 97 species in all 114 species were C_3 plants and only 17 species were C_4 plants. Most C_4 plants belonged to Gramineae family. The foliar δ^(13)C value of C_3 plants was between -25.000 and -31.075‰ with an average of-28.226‰, while those of C_4 plants between -12.578 and -16.334‰, with an average of -13.678‰. The δ^(13)C values of mature leaves collected in August were averagely 0.85‰ less than that of juvenile leaves collected in June. The foliar δ^(13)C values and WUE of 15 sand-fixing tree species in Horqin sandy land ranked in the order as: S.vulgaris >H.rhamnoides >C.ovata >P.mongolica >T.chinensis >R.typhina >S.matsudana >E.angustifolia >U.pumila >S.gordejevii >X.sorbifolia >C.microphylla >H.fruticosum >C.korshinskii >E.bungeanus.
基金supported by the National Key Research and Development Program of China(2018YFD0300705 and 2017YFD0301101)the National Key Technologies R&D Program of China during the 13th Five-Year Plan period(2013BAD07B14)+1 种基金the Key Science and Technology Program of Higher Education Institutions in Henan Province,China(20B210017)the Scientific and Technological Project of Henan Province,China(202102110168)。
文摘Grain zinc(Zn) and iron(Fe) concentrations and their responses to foliar application of micronutrients in 28 Chinese wheat landraces and 63 cultivars were investigated in a two-year field experiment. The average grain Zn and Fe concentrations were 41.8 mg kg^(-1)(29.0-63.3 mg kg^(-1)) and 39.7 mg kg^(-1)(27.9-67.0 mg kg^(-1)), respectively. Compared with cultivars, landraces had greater grain Zn(11.0%) and Fe(4.8%) concentrations but lower harvest index(HI), grain weight per spike(GWS), grain number per spike(GNS) and thousand grain weight(TGW). Both Zn and Fe concentrations were negatively and significantly correlated with HI, GWS, and GNS, while showed a poor association with TGW, suggesting that lower HI, GWS, and GNS, but not TGW, accounted for higher Zn and Fe concentrations for landraces than for cultivars. Grain Zn concentrations of both cultivars and landraces significantly increased after foliar Zn spray and the increase was two-fold greater for landraces(12.6 mg kg^(-1)) than for cultivars(6.4 mg kg^(-1)). Foliar Fe spray increased grain Fe concentrations of landraces(3.4 mg kg^(-1)) and cultivars(1.2 mg kg^(-1)), but these increases were not statistically significant. This study showed that Chinese wheat landraces had higher grain Zn and Fe concentrations than cultivars, and greater increases occurred in grain Zn concentration than in grain Fe concentration in response to fertilization, suggesting that Chinese wheat landraces could serve as a potential genetic source for enhancing grain mineral levels in modern wheat cultivars.
文摘Bt cotton hybrids require large supply of metabolites to support their greater boll load and commonly suffer from premature leaf senescence. A field experiment was conducted to study the nutritional status of Bt cotton leaves during boll development stage and to evaluate the most profitable source of foliar fertilizers. Treatments included basal application of 0 and 60 kg·K2O·ha-1 as muriate of potash (MOP) in main plots and foliar spray treatments viz: 4 & 6 sprays of 2% potassium nitrate (Multi-K, 13-00-45), 4 & 6 sprays of NPK Blend (Polyfed, 19-19-19), 4 sprays of MOP, 4 sprays of MOP + urea (to supply same amount of N & K as in potassium nitrate) and unsprayed control in sub plots. The results revealed that only N and K contents of premature senesced leaves were below the sufficiency range for cotton sufficient levels of P, Fe, Mn, Zn and Cu were observed. Though the concentrations of N and K in both the petiole and leaf blade initially improved with foliar spray, N content declined below the unsprayed control at later stages. Basal application of MOP increased seed cotton yield by 19%. Four foliar sprays of KNO3, NPK, MOP and MOP + urea recorded yield increase in seed cotton yield of 22.8%, 22.4%, 18.5% and 24.5%, respectively over unsprayed control. Six sprays of KNO3 and NPK had no yield advantage over four sprays and rather proved economically less viable.
文摘The objective of this research was to evaluate the effectiveness of soil and foliar application of potassium (K) on leaf and seed mineral concentration levels, and seed composition (protein, oil, fatty acids, and minerals). Soybean cultivar (Pioneer 95470) of maturity group 5.7 was grown in a repeated greenhouse experiment in a randomized complete block design. Treatment consisted of two concentrations of foliar K application (T1, rate of 1.75% and T2, rate of 2.5%) and soil application (T3, rate of 190 mg/kg and T4, rate of 380 mg/kg). Potassium was applied for each type at V3 (vegetative) and R3 (beginning of seed pod initiation) stages. The results showed higher K and S concentrations in leaves in T1 and T2. The concentrations of B and Zn decreased in all treatments, whereas Fe concentration increased in T1 and T3. In seeds, most mineral concentrations were stable, except for Fe which increased in both T1 and T3. Seed protein percentage increased 3.0% in T3 compared with the control (no K application). Seed oil percentage showed a general decrease in all the treatments, except for 3.2% increase in T4. Palmitic acid percentages showed significant increase in all concentrations, the highest percentage increase of 16.9% was observed in T4. Stearic acid increased in T2 and T3. Linoleic acid percentages increased in both foliar treatments, but linolenic acid percentage increased in high soil treatment T4 alone, with an increase of 12.2% in comparison to the control. Significant decrease (15.8%) in linoleic acid was found in foliar application, T2. Oleic acid decreased uniformly in all treatments, where the highest decrease (19.2%) was observed in soil application, T4. Our research demonstrated that both foliar and soil application of K were found to selectively alter seed composition. Further research is needed to be conducted under field conditions before conclusions can be made.