Improving crop nutrient ef ficiency becomes an essential consideration for environmentally friendly and sustainable agriculture. Plant growth and development is dependent on 17 essential nutrient elements,among them,n...Improving crop nutrient ef ficiency becomes an essential consideration for environmentally friendly and sustainable agriculture. Plant growth and development is dependent on 17 essential nutrient elements,among them,nitrogen(N) and phosphorus(P) are the two most important mineral nutrients. Hence it is not surprising that low N and/or low P availability in soils severely constrains crop growth and productivity,and thereby have become high priority targets for improving nutrient ef ficiency in crops. Root exploration largely determines the ability of plants to acquire mineral nutrients from soils. Therefore,root architecture,the 3-dimensional con figuration of the plant's root system in the soil,is of great importance for improving crop nutrient ef ficiency. Furthermore,the symbiotic associations between host plants and arbuscular mycorrhiza fungi/rhizobial bacteria,are additional important strategies to enhance nutrient acquisition. In this review,we summarize the recent advances in the current understanding of crop species control of root architecture alterations in response to nutrient availability and root/microbe symbioses,through gene or QTL regulation,which results in enhanced nutrient acquisition.展开更多
Increasing crop yields can provide food,animal feed, bioenergy feedstocks and biomaterials to meet increasing global demand; however, the methods used to increase yield can negatively affect sustainability. For exampl...Increasing crop yields can provide food,animal feed, bioenergy feedstocks and biomaterials to meet increasing global demand; however, the methods used to increase yield can negatively affect sustainability. For example, application of excess fertilizer can generate and maintain high yields but also increases input costs and contributes to environmental damage through eutrophication, soil acidification and air pollution. Improving crop nutrient efficiency can improve agricultural sustainability by increasing yield while decreasing input costs and harmful environmental effects. Here, we review the mechanisms of nutrient efficiency(primarily for nitrogen, phosphorus, potassium and iron) and breeding strategies for improving this trait, along with the role of regulation of gene expression in enhancing crop nutrient efficiency to increase yields. We focus on the importance of root system architecture to improve nutrient acquisition efficiency, as well as the contributions of mineral translocation, remobilization and metabolic efficiency to nutrient utilization efficiency.展开更多
Nitrogen(N)and phosphorus(P)are two essential nutrients that determine plant growth and many nutrient cycling processes.Increasing N and P deposition is an important driver of ecosystem changes.However,in contrast to ...Nitrogen(N)and phosphorus(P)are two essential nutrients that determine plant growth and many nutrient cycling processes.Increasing N and P deposition is an important driver of ecosystem changes.However,in contrast to numerous studies about the impacts of nutrient addition on forests and temperate grasslands,how plant foliar stoichiometry and nutrient resorption respond to N and P addition in alpine grasslands is poorly understood.Therefore,we conducted an N and P addition experiment(involving control,N addition,P addition,and N+P addition)in an alpine grassland on Kunlun Mountains(Xinjiang Uygur Autonomous Region,China)in 2016 and 2017 to investigate the changes in leaf nutrient concentrations(i.e.,leaf N,Leaf P,and leaf N:P ratio)and nutrient resorption efficiency of Seriphidium rhodanthum and Stipa capillata,which are dominant species in this grassland.Results showed that N addition has significant effects on soil inorganic N(NO_(3)^(-)-N and NH_(4)^(+)-N)and leaf N of both species in the study periods.Compared with green leaves,leaf nutrient concentrations and nutrient resorption efficiency in senesced leaves of S.rhodanthum was more sensitive to N addition,whereas N addition influenced leaf N and leaf N:P ratio in green and senesced leaves of S.capillata.N addition did not influence N resorption efficiency of the two species.P addition and N+P addition significantly improved leaf P and had a negative effect on P resorption efficiency of the two species in the study period.These influences on plants can be explained by increasing P availability.The present results illustrated that the two species are more sensitive to P addition than N addition,which implies that P is the major limiting factor in the studied alpine grassland ecosystem.In addition,an interactive effect of N+P addition was only discernable with respect to soil availability,but did not affect plants.Therefore,exploring how nutrient characteristics and resorption response to N and P addition in the alpine grassland is important to understand nutrient use strategy of plants in terrestrial ecosystems.展开更多
The development of green super rice varieties with improved nutrient use efficiency(NuUE)is a vital target area to increase yield and make it more stable under rainfed conditions.In the present study, we followed an e...The development of green super rice varieties with improved nutrient use efficiency(NuUE)is a vital target area to increase yield and make it more stable under rainfed conditions.In the present study, we followed an early backcross(BC) breeding approach by using a highyielding and widely adapted Xian variety, Weed Tolerant Rice 1(WTR-1), as a recipient and a Geng variety, Hao-An-Nong(HAN), as a donor.Starting from the BC1F2 generation, the BC population went through one generation of selection under irrigated, low-input, and rainfed conditions, followed by four consecutive generations of screening and selection for high grain yield(GY) under six different nutrient conditions(NPK, 75 N,-N,-P,-NP, and-NPK), leading to the development of 230 BC1F6 introgression lines(ILs).These 230 ILs were evaluated under the same six nutrient conditions for 13 agro-morphological and grain yield component traits in comparison to four checks and parents.Significant trait variations were observed between the treatments and ILs.Positive correlations were identified for GY with biomass, panicle length, flag-leaf area, flag-leaf width, filled grain number per panicle,1000-grain weight, and tiller number under-N,-P,-NP, and-NPK conditions.Out of 230 ILs,12 were identified as promising under two or more nutrient deficiency conditions.The results demonstrated an efficient inter-subspecific BC breeding procedure with a first round of selection under rainfed-drought conditions, followed by four generations of progeny testing for yield performance under six nutrient conditions.The promising ILs can be useful resources for molecular genetic dissection and understanding the physiological mechanisms of NuUE.展开更多
The primary challenge of mineland revegetation is the establishment of species able to cope with low availability of nutrients,especially in steep slopes such as of mine pits.We evaluated plant growth response and nut...The primary challenge of mineland revegetation is the establishment of species able to cope with low availability of nutrients,especially in steep slopes such as of mine pits.We evaluated plant growth response and nutrient use efficiency(NUE)of two promising native Fabaceae species(Dioclea apurensis—liana from metalliferous savannas;Bauhinia longipedicellata—tree from Amazon rainforest)from the Caraja´s Mineral Province,eastern Amazon-Brazil.Plants were grown separately in 2-kg pots filled with mining waste.Substrates were fertilized with nitrogen,phosphorus,potassium(NPK),lime,and micronutrients.The results showed increments on growth of both species when nutrients were applied to the mining waste.D.apurensis showed increases in leaf area,plant height,stem diameter,and shoot dry mass production when NPK or NPK?micronutrients were applied,while B.longipedicelata was responsive to application of NPK?lime or NPK?lime?micronutrients.Further,D.apurensis showed higher NUE than B.longipedicelata,especially at the lowest doses of N,P and K.These findings may indicate a substantial advantage of D.apurensis for mineland revegetation,as this species may require lower nutrient inputs,being,therefore,a more sustainable way to revegetate degraded areas.展开更多
In Saint-Louis, Senegal, a constructed wetland with horizontal flow reed beds (FHa and FHb) has demonstrated significant efficacy in treating municipal wastewater. Analyzing various treatment stages, the system showed...In Saint-Louis, Senegal, a constructed wetland with horizontal flow reed beds (FHa and FHb) has demonstrated significant efficacy in treating municipal wastewater. Analyzing various treatment stages, the system showed only a slight temperature variation, from an influent average of 26.3°C to an effluent of 24.7°C. Electrical conductivity decreased from 1331 mS/cm to 974.5 mS/cm post-primary treatment, with suspended solids (SS) dramatically reduced from 718.9 mg/L to 5.7 mg/L in the final effluent. Biochemical oxygen demand (BOD5) and chemical oxygen demand (COD) saw a notable decrease, from initial levels of 655.6 mg/L and 1240 mg/L to 2.3 mg/L and 71.3 mg/L, respectively. Nitrogenous compounds (N-TN) and phosphates () also decreased significantly, indicating the system’s nutrient removal capacity. Microbiological analysis revealed a reduction in fecal coliforms from 7.5 Ulog/100ml to 1.8 Ulog/100ml and a complete elimination of helminth eggs. The presence of Phragmites and Typha was instrumental in enhancing these reductions. The system’s compliance with the Senegalese standards for disposal into natural environments, WHO recommendations for unrestricted water reuse in irrigation, and the European legislation for water reuse was established. The effluent quality met the stringent criteria for various classes of agricultural reuse, illustrating the system’s potential for sustainable water management. This wetland model presents a robust solution for water-stressed regions, ensuring environmental protection while supporting agricultural needs. The study calls for ongoing research to further refine the system for optimal, reliable wastewater treatment and water resource sustainability.展开更多
China is in a dominant position in apple production globally with both the largest apple growing area and the largest export of fresh apple fruits. However, the annual productivity of China's apple is significantly l...China is in a dominant position in apple production globally with both the largest apple growing area and the largest export of fresh apple fruits. However, the annual productivity of China's apple is significantly lower than that of other dominant apple producing countries. In addition, apple production is based on excessive application of chemical fertilizers and the nutrient use efficiency (especially nitrogen) is therefore low and the nutrient emissions to the environment are high. Apple production in China is considerably contributes to farmers' incomes and is important as export product. There is an urgent need to enhance apple productivity and improve nutrient use efficiencies in intensive apple production systems in the country. These can be attained by improved understanding of production potential, yield gaps, nutrient use and best management in apple orchards. To the end, priorities in research on apple production systems and required political support are described which may lead to more sustainable and environmental-friendly intensification of apple production in China.展开更多
The success of the Green Revolution largely relies on fertilizers, and a new Green Revolution is very much needed to use fertilizers more economically and efficiently, as well as with more environmental responsibility...The success of the Green Revolution largely relies on fertilizers, and a new Green Revolution is very much needed to use fertilizers more economically and efficiently, as well as with more environmental responsibility. The use efficiency of nitrogen, phosphorus, and potassium is controlled by complex gene networks that co-ordinate uptake, re-distribution, assimilation, and storage of these nutrients. Great progress has been made in breeding nutrient-efficient crops by molecularly engineering root traits desirable for efficient acquisition of nutrients from soil, transporters for uptake, redistribution and homeostasis of nutrients, and enzymes for efficient assimilation. Regulatory and transcription factors modulating these processes are also valuable in breeding crops with improved nutrient use efficiency and yield performance.展开更多
Optimal planting density and proper fertilization method are important factors to improve maize yield and nutrient utilization. A two-year(2016 and 2017) field experiment was conducted with three plant densities(6.0, ...Optimal planting density and proper fertilization method are important factors to improve maize yield and nutrient utilization. A two-year(2016 and 2017) field experiment was conducted with three plant densities(6.0, 7.5 and 9.0 plants m^-2) and three fertilization modes(no fertilizer, 0 F;one-off application of slow-released fertilizer, SF;twice application of conventional fertilizer, CF). Results indicated that the grain yields and N, P and K use efficiencies under SF with the optimal planting density(7.5 plants m^-2) were the highest among all the treatments in 2016 and 2017. Compared with CF, SF could increase post-silking dry matter accumulation and promote N, P and K uptake at pre-and post-silking stages;this treatment increased grain N, P and K concentrations and resulted in high N, P and K use efficiencies. Nutrient(N, P and K) absorption efficiencies and partial productivity, and nutrient(N and P) recovery efficiency in SF treatment were significantly higher than those in CF treatments under the planting density of 7.5 plants m^-2. Under both SF and CF conditions, the grain yield, total N accumulation and nutrient use efficiencies initially increased, peaked at planting density of 7.5 plants m^-2, and then decreased with increasing plant density. Based on the yield and nutrient use efficiency in two years, plant density of 7.5 plants m^-2 with SF can improve both the grain yield and N, P and K use efficiency of spring maize in Jiangsu Province, China.展开更多
We studied leaf litter fall, decomposition and nutrient release patterns of Shorea robusta and Tectona grandis by using a litter bag technique to better understand the release pattern of nutrients to soil from leaf li...We studied leaf litter fall, decomposition and nutrient release patterns of Shorea robusta and Tectona grandis by using a litter bag technique to better understand the release pattern of nutrients to soil from leaf litter. Annual litterfall varied from 13.40 ± 2.56 t ha-1 a-1 for S. robusta to 11.03 ± 3.72 t ha-1 a-1 for T. grandis and the decay constant (k) of decomposed leaf litter was distinctly higher for T. grandis (2.70 ± 0.50 a-1) compared to S. robusta (2.41 ±0.30 a-1). Biomass loss was positively correlated with the initial litter C, WSC, C/N and ash content in S. robusta and N, P and K concentration for T. grandis. Biomass was negatively correlated with lignin and L/N ratio for S. robusta and L, WSC, L/N and C/N ratio for T. grandis (P 〈 0.01). Nutrient use efficiency (NUE) and nutrient accumulation index (NAI) of S. robusta was higher than for T. grandis. The retranslocation of bioelements from senescent leaves ranked as P 〉 N 〉 K. Annual N, P and K input to soil through litterfall differed significantly between the two species in the following order: N〉K^P. S. robusta was superior in terms of K and P return and T. grandis was superior in terms of N return. The two tree species showed a similar patterns of nutrient release (K 〉 P 〉 N) during decomposition of their leaf litter.Nutrients of N, K and P were the primary limiting nutrients returned to soil through litterfall with important roles in soil fertility and forest productivity.展开更多
Nutrient balance is essential for attaining high yield and improving profits in agricultural farming systems,and crop nutrient uptake ratio and stoichiometry can indicate crop nutrient limitations in the field.We coll...Nutrient balance is essential for attaining high yield and improving profits in agricultural farming systems,and crop nutrient uptake ratio and stoichiometry can indicate crop nutrient limitations in the field.We collected a large amount of field data to study the variations in yield,nutrient uptake and nutrient stoichiometry of peanut(Arachis hypogaea L.)in Southeast China(SEC),North-central China(NCC),and Northeast China(NEC),during 1993 to 2018.Peanut pod yield gradually increased from 1993 to 2018,with average yields of 4148,5138,and 4635 kg ha–1 in SEC,NCC,and NEC,respectively.The nitrogen(N)internal efficiency(NIE,yield to N uptake ratio)was similar among the three regions,but phosphorus(P)IE(PIE,yield to P uptake ratio)changed from low to high among regions:NCC<SEC<NEC,while potassium(K)IE(KIE,yield to K uptake ratio)portrayed a different pattern of SEC<NCC<NEC.Based on the nutrient IE,to produce 1 Mg of pod yield,the average N,P,and K requirements of the above-ground parts of peanut were roughly 47.2,5.1,and 25.5 kg in SEC,44.8,5.7,and 20.6 kg in NCC,and 44.6,4.4,and 14.7 kg in NEC,respectively.The N/P ratio changed in the sequence NCC<SEC<NEC,and the N/K ratio was similar in NEC and NCC,but lower in SEC.The N harvest index(HI)and KHI declined with increasing nutrient uptake across all regions under high nutrient uptake.The low PIE and N/P ratios in NCC could be explained by the high P accumulation in stover,and high KIE and N/K ratios in NEC may be attributed to the low soil K supply.The frontier analysis approach provides a practical framework and allows documentation of a decline in nutrient HI as nutrient uptake increases.Lastly,this study reveals the limitation and surplus of nutrients of peanut in different regions of China.展开更多
This study was executed to offer the basis for optimized profit from fertilizer use for sorghum yield and to determine robust crop nutrient response function and economic rate for the production of sorghum at Miesso C...This study was executed to offer the basis for optimized profit from fertilizer use for sorghum yield and to determine robust crop nutrient response function and economic rate for the production of sorghum at Miesso Central Rift Valley of Ethiopia. Trails were conducted at six experimental sites, sorghum yield response to N and P fertilizers application and economically optimum rates of nitrogen (EONR) and phosphorus (EOPR) were evaluated on a vertisols within the semi-arid Miesso districts west Hararge zone of Oromia region. The nutrient rates in 2014 cropping season four levels of Nitrogen (N) alone, these levels with 20 <span style="white-space:nowrap;">kg·ha<sup>−1</sup></span> Phosphorus (P) and without N, 69 kg<span style="white-space:nowrap;">·</span>ha<sup><span style="white-space:nowrap;">−</span>1</sup> N with three levels of P treatments including the zero control were evaluated. In 2015, cropping season similar rates of N alone, the same rate N with 20 <span style="white-space:nowrap;">kg·ha<sup>−1</sup></span> P, 92 <span style="white-space:nowrap;">kg·ha<sup>−1</sup></span> N with three rates of P including the zero control were evaluated. The treatments were arranged in a randomized complete block with three replications in factorial design. Nutrient responses of sorghum were determined using asymptotic quadratic plateau functions. The significantly highest nitrogen rate was 46 <span style="white-space:nowrap;">kg·ha<sup>−1</sup></span> alone in 2014 season, which gave grain yield of 2.56 Mg<span style="white-space:nowrap;">·ha<sup>−1</sup></span><sup> </sup>with a maximum yield advantage of 43%. P rates in both seasons and combined (sites + seasons) were not significantly influenced sorghum yield. Nitrogen agronomic and partial factor productivity peaked at 23 kg N <span style="white-space:nowrap;">ha<sup>−1</sup></span> but declined with increasing N rate. The EONR combined (sites + seasons) were 37, 45, 52 and 60 <span style="white-space:nowrap;">kg·ha<sup>−1</sup></span><sup> </sup>and for the profit to cost ratio (PCR) were 2.43, 3.65, 4.86 and 5.79 at difference cost to grain price ratios (CP) = 3.6, 2.3, 1.6 and 1.2 respectively at Miesso Ethiopia. Nitrogen application had economically profitable than P. The study concluded that the application of N at 37 or 60 kg N <span style="white-space:nowrap;">ha<sup>−1</sup></span> to sorghum production could be economically profitable for those economically constrained farmers or economically not constrained farmers. Validation should be farther conducted on farmers’ fields for refining the results obtained.展开更多
Physiological characteristics of rice at different Zn^(2+) levels[pZn^(2+)>11.5, 11.3, 11.0, 10.6, 10.3, 9.7] were studied with the Zn-efficient rice cultivars IR34, IR36, IR8192, and Zn-inefficient rice cultivars ...Physiological characteristics of rice at different Zn^(2+) levels[pZn^(2+)>11.5, 11.3, 11.0, 10.6, 10.3, 9.7] were studied with the Zn-efficient rice cultivars IR34, IR36, IR8192, and Zn-inefficient rice cultivars IR26, Ce 64-7, Biyuzaonuo, which grew in chelator-buffered nutrient solution. There were significant differences in tolerance to zinc deficiency among different rice genotypes. Obvious effects of low zinc activity on the physiological characteristic of rice seedlings were noted. There were significant differences in chlorophyll content, photosynthesis rate, MDA concentration in rice leaf, and H^+ excretion of root. As pZn^(2+) decreased, chlorophyll content and photosynthesis rate decreased at a slower pace in Zn-efficient cultivars compared to Zn-inefficient ones, MDA concentration increased slower while H^+ excretion of root increased faster in Zn-efficient cultivars than those in Zn-inefficient ones. It was suggested that the above indications could be used as indexes to Zn-efficiency of rice.展开更多
Root system architecture(RSA)plays a pivotal role in efficient uptake of essential nutrients,such as phosphorous(P),nitrogen(N),and water In soils with heterogeneous nutrient distribution,root plasticity can optimize ...Root system architecture(RSA)plays a pivotal role in efficient uptake of essential nutrients,such as phosphorous(P),nitrogen(N),and water In soils with heterogeneous nutrient distribution,root plasticity can optimize acquisition and plant growth.Here,we present evidence that a constitutive RSA can confer benefits for sorghum grown under both sufficient and limiting growth conditions.Our studies,using P efficient SC103 and inefficient BTx635 sorghum cultivars,identified significant differences in root traits,with SC103 developing a larger root system with more and longer lateral roots,and enhanced shoot biomass,under both nutrient sufficient and deficient conditions.In addition to this constitutive attribute,under P deficiency,both cultivars exhibited an initial increase in lateral root development;however,SC103 still maintained the larger root biomass.Although N deficiency and drought stress inhibited both root and shoot growth,for both sorghum cultivars,SC103 again maintained the better performance.These findings reveal that SC103,a P efficient sorghum cultivar,also exhibited enhanced growth performance under N deficiency and drought.Our results provide evidence that this constitutive nature of RSA can provide an avenue for breeding nutrient-and drought-resilient crops.展开更多
Abiotic stresses and soil nutrient limitations are major environmental conditions that reduce plant growth,productivity and quality.Plants have evolved mechanisms to perceive these environmental challenges,transmit th...Abiotic stresses and soil nutrient limitations are major environmental conditions that reduce plant growth,productivity and quality.Plants have evolved mechanisms to perceive these environmental challenges,transmit the stress signals within cells as well as between cells and tissues,and make appropriate adjustments in their growth and development in order to survive and reproduce.In recent years,significant progress has been made on many fronts of the stress signaling research,particularly in understanding the downstream signaling events that culminate at the activation of stress-and nutrient limitation-responsive genes,cellular ion homeostasis,and growth adjustment.However,the revelation of the early events of stress signaling,particularly the identification of primary stress sensors,still lags behind.In this review,we summarize recent work on the genetic and molecular mechanisms of plant abiotic stress and nutrient limitation sensing and signaling and discuss new directions for future studies.展开更多
Three diploid (Triticum boeoticum, AA; Aegilops speltoides, BB and Ae. tauschii, DD), two tetraplold (T. dlcoccoides, AABB and T. dicoccon, AABB) and one hexapioid (T. vulgare, AABBDD) varieties of wheat, which ...Three diploid (Triticum boeoticum, AA; Aegilops speltoides, BB and Ae. tauschii, DD), two tetraplold (T. dlcoccoides, AABB and T. dicoccon, AABB) and one hexapioid (T. vulgare, AABBDD) varieties of wheat, which are very important In the evolution of wheat were chosen in this study. A pot experiment was carried out on the wheat under different water and nutrient conditions (i) to understand the differences in biomass, yield, water use efficiency (WUE), and nutrient (N, P and K) use efficiency (uptake and utilization efficiency) among ploidies in the evolution of wheat; (li) to clarify the effect of water and nutrient conditions on water and nutrient use efficiency; and (ill) to assess the relationship of water and nutrient use efficiency in the evolution of wheat. Our results showed that from diploid to tetraplold then to hexaploid during the evolution of wheat, both root biomass and above-ground biomass Increased Initially and then decreased. Water consumption for transpiration decreased remarkably, correlating with the decline of the growth period, while grain yield, harvest index, WUE, N, P and K uptake efficiency, and N, P and K utilization efficiency Increased significantly. Grain yield, harvest index and WUE decreased In the same order: T. vulgare 〉 T. dicoccon 〉 T. dicoccoides 〉 Ae. tauschii 〉 Ae. speltoides 〉 T. boeoticum. Water stress significantly decreased root blomass, above-ground biomass, yield, and water consumption for transpiration by 47-52%, but remarkably Increased WUE. Increasing the nutrient supply increased wheat above-ground biomass, grain yield, harvest Index, water consumption for transpiration and WUE under different water levels, but reduced root blomass under drought conditions. Generally, water stress and low nutrient supply resulted in the lower nutrient uptake efficiency of wheat. However, water and nutrient application had no significant effects on nutrient utilization efficiency, suggesting that wheat nutrient utilization efficiency is mainly controlled by genotypes. Compared to the other two diploid wheats, Ae. squarrosa (DD) had significant higher WUE and nutrient utilization efficiency, Indicating that the D genome may carry genes controlling high efficient utilization of water and nutrient. Significant relation- ships were found between WUE and N, P and K utilization efficiency.展开更多
We conducted a study to find out if arbuscular mycorrhizal(AM) fungi(Acaulospora scrobiculata,Scutellospora calospora) and phosphate solubilizing bacteria(PSB, Paenibacillus polymyxa) inoculation either individually o...We conducted a study to find out if arbuscular mycorrhizal(AM) fungi(Acaulospora scrobiculata,Scutellospora calospora) and phosphate solubilizing bacteria(PSB, Paenibacillus polymyxa) inoculation either individually or in combinations can improve Acacia auriculiformis seedling growth, uptake of nutrients and quality in a phosphorus deficient tropical Alfisol. The seedlings were assessed for various growth and nutrient uptake parameters after 60 days of treatment. Inoculation with P.polymyxa stimulated mycorrhizal formation. Seedling height, stem girth, taproot length, number of leaves and leaf area, plant dry matter production, nodulation, and nodular dry weight were significantly higher for seedlings that were either dual inoculated or triple inoculated compared to individual inoculation of AM fungi or PSB, and uninoculated seedlings. Dual and triple application of AM fungi and PSB also significantly improved the nutrient contents of shoots and roots and nutrient uptake efficiencies. The calculated seedling quality indexes of the AM fungi and PSB inoculated seedling were 25–208% higher than uninoculated seedlings. These findings show that A.auriculiformis seedlings when dual inoculated or triple inoculated performed better than seedlings inoculated with the microbes individually and compared with uninoculated control seedlings. We conclude that bioinoculation is important for the production of high-quality A.auriculiformis seedlings in tree nurseries for planting in nutrient deficient soils.展开更多
Teak (Tectona grandis Linn. f.) ranks among the top five tropical hardwood species and is being promoted for use in plantations in its non-native range due to its high economic value. However, there is a general lac...Teak (Tectona grandis Linn. f.) ranks among the top five tropical hardwood species and is being promoted for use in plantations in its non-native range due to its high economic value. However, there is a general lack of data on ecosystem functioning of teak plantations. We aimed at understanding storage and flux of nutrients related to young plantations of teak. Cycling of nitrogen (N) and phosphorus (P) in a chronosequence of plantations (1, 5, 11, 18, 24 and 30 years) was studied in the Moist Deciduous Forest Region of North India with the objective of investigating the nutrient cycling pattern at younger age since the current trend of harvesting age of the species in several tropical countries is being drastically reduced for quick return from this high value crop. Standing state, nutrient uptake, nutrient return and nutrient retransloca-tion in these plantations were estimated by tree harvesting and chemical analysis methods. The range of total standing nutrient across all these plantations was 20.3 to 586.6 kg?ha-1 for N and 5.3 to 208.8 kg?ha-1 for P. Net uptake of N ranged from 19.4 to 88.9 kg?ha-1?a-1 and P from 3.8 to 18.1 kg?ha-1?a-1. Retranslocation of N and P among all the stands ranged from 8.7 to 48.0 kg?ha-1?a-1 and 0.01 to 3.5 kg?ha-1?a-1, respectively. Range of total nutrient return was 25.8 to 91.3 kg?ha-1?a-1 for N and 2.7 to 10.1 kg?ha-1?a-1 for P. N and P use efficiency was between 107.4 and 192.5 g dry organic matter (OM) g-1N, and 551.9 and 841.1 g OM g-1P, respec-tively. The turnover time ranged from 2.04-13.17 years for N and be-tween 2.40-22.66 years for P. Quantity of N and P in the soil nutrient pool ranged from 2566.8 to 4426.8 kg?ha-1 and 372 to 520 kg?ha-1, re-spectively. Storage and flux of components in different plant parts of different aged plantations were assessed and depicted in compartment models. Percentage storage in soil, litter and vegetation ranged from 82% to 99%, 0.6% to 2.4% and 0.5% to 15% for N, respectively, and from 63% to 98%, 0.5% to 2% and 1% to 35% for P, respectively. This infor-mation could be useful in managing external nutrient manipulation to crops of different ages for optimum biomass production or carbon se-questration.展开更多
Given the central role of light in the algal photosynthesis,respiration,cell division,growth and the accumulation of value products,the effects of light-emitting diodes(LEDs)light wavelengths(blue,white,red and green)...Given the central role of light in the algal photosynthesis,respiration,cell division,growth and the accumulation of value products,the effects of light-emitting diodes(LEDs)light wavelengths(blue,white,red and green)were studied in Scenedesmus obliquus.Biomass,residual nutrient amount,soluble protein,astaxanthin and reactive oxygen species,superoxide dismutase(SOD),catalase(CAT)and peroxidase(POD)activity were analyzed to determine the effects of different monochromatic light wavelengths via biochemical methods.The results showed that blue light wavelength is the optimal light wavelength for phosphorus removal efficiency and the accumulation of biomass and astaxanthin in S.obliquus.Meanwhile,high reactive oxygen species content under the blue light might induce the accumulation of astaxanthin.The high activity of SOD,CAT and POD might participate in clearing the reactive oxygen species to facilitate the growth of microalgae.Furthermore,we found mixed blue/green lights treatment is the most appropriate mixture for the nitrogen removal.Under the blue light treatment,high light intensity and 18L:6D light cycle is the best condition for biomass and astaxanthin accumulation.Optimal nitrogen/phosphorus removal efficiency was observed under a 24L:0D light cycle.These results might provide a foundational data for the optimizing the productivity of high-value metabolites and treatment of wastewater.展开更多
[Objectives]To systematically study the effects of different nitrogen levels on the growth and nitrogen utilization of sugarcane in Guangxi.[Methods]Through field experiment and indoor analysis,different nitrogen appl...[Objectives]To systematically study the effects of different nitrogen levels on the growth and nitrogen utilization of sugarcane in Guangxi.[Methods]Through field experiment and indoor analysis,different nitrogen application levels were set up to determine soil nitrogen content and sugarcane nitrogen content.The effects of different nitrogen levels on sugarcane yield,agronomic characters and nitrogen utilization were studied.[Results]The effect of nitrogen application rate on sugarcane yield showed a quadratic curve,and nitrogen application could significantly increase sugarcane yield,and the sugarcane yield reached the maximum when the nitrogen application rate reached 714 kg/ha.[Conclusions]With the increase of nitrogen application rate,sugarcane yield increased,but when it exceeded a certain range,the sugarcane yield decreased significantly.展开更多
基金the National Natural Science Foundation of China (U1301212)the Strategic Priority Research Program of the Chinese Academy of Sciences (XDB15030202)
文摘Improving crop nutrient ef ficiency becomes an essential consideration for environmentally friendly and sustainable agriculture. Plant growth and development is dependent on 17 essential nutrient elements,among them,nitrogen(N) and phosphorus(P) are the two most important mineral nutrients. Hence it is not surprising that low N and/or low P availability in soils severely constrains crop growth and productivity,and thereby have become high priority targets for improving nutrient ef ficiency in crops. Root exploration largely determines the ability of plants to acquire mineral nutrients from soils. Therefore,root architecture,the 3-dimensional con figuration of the plant's root system in the soil,is of great importance for improving crop nutrient ef ficiency. Furthermore,the symbiotic associations between host plants and arbuscular mycorrhiza fungi/rhizobial bacteria,are additional important strategies to enhance nutrient acquisition. In this review,we summarize the recent advances in the current understanding of crop species control of root architecture alterations in response to nutrient availability and root/microbe symbioses,through gene or QTL regulation,which results in enhanced nutrient acquisition.
基金funding from the Ministry of Science and Technology Key R&D Program (2016YFD0100700)
文摘Increasing crop yields can provide food,animal feed, bioenergy feedstocks and biomaterials to meet increasing global demand; however, the methods used to increase yield can negatively affect sustainability. For example, application of excess fertilizer can generate and maintain high yields but also increases input costs and contributes to environmental damage through eutrophication, soil acidification and air pollution. Improving crop nutrient efficiency can improve agricultural sustainability by increasing yield while decreasing input costs and harmful environmental effects. Here, we review the mechanisms of nutrient efficiency(primarily for nitrogen, phosphorus, potassium and iron) and breeding strategies for improving this trait, along with the role of regulation of gene expression in enhancing crop nutrient efficiency to increase yields. We focus on the importance of root system architecture to improve nutrient acquisition efficiency, as well as the contributions of mineral translocation, remobilization and metabolic efficiency to nutrient utilization efficiency.
基金This research was supported by the National Natural Science Foundation of China(41807335)the Shandong Provincial Natural Science Foundation,China(ZR2020MC040)+2 种基金the National Key Technology Research and Development Program of China(2019YFC0507602-2)the Youth Innovation Promotion Association of the Chinese Academy of Sciences(2020434)the National Postdoctoral Program for Innovative Talents(BX201700279).
文摘Nitrogen(N)and phosphorus(P)are two essential nutrients that determine plant growth and many nutrient cycling processes.Increasing N and P deposition is an important driver of ecosystem changes.However,in contrast to numerous studies about the impacts of nutrient addition on forests and temperate grasslands,how plant foliar stoichiometry and nutrient resorption respond to N and P addition in alpine grasslands is poorly understood.Therefore,we conducted an N and P addition experiment(involving control,N addition,P addition,and N+P addition)in an alpine grassland on Kunlun Mountains(Xinjiang Uygur Autonomous Region,China)in 2016 and 2017 to investigate the changes in leaf nutrient concentrations(i.e.,leaf N,Leaf P,and leaf N:P ratio)and nutrient resorption efficiency of Seriphidium rhodanthum and Stipa capillata,which are dominant species in this grassland.Results showed that N addition has significant effects on soil inorganic N(NO_(3)^(-)-N and NH_(4)^(+)-N)and leaf N of both species in the study periods.Compared with green leaves,leaf nutrient concentrations and nutrient resorption efficiency in senesced leaves of S.rhodanthum was more sensitive to N addition,whereas N addition influenced leaf N and leaf N:P ratio in green and senesced leaves of S.capillata.N addition did not influence N resorption efficiency of the two species.P addition and N+P addition significantly improved leaf P and had a negative effect on P resorption efficiency of the two species in the study period.These influences on plants can be explained by increasing P availability.The present results illustrated that the two species are more sensitive to P addition than N addition,which implies that P is the major limiting factor in the studied alpine grassland ecosystem.In addition,an interactive effect of N+P addition was only discernable with respect to soil availability,but did not affect plants.Therefore,exploring how nutrient characteristics and resorption response to N and P addition in the alpine grassland is important to understand nutrient use strategy of plants in terrestrial ecosystems.
基金the Bill & Melinda Gates Foundation (BMGF) for providing a research grant to Z.L.for the Green Super Rice project under ID OPP1130530the Department of Agriculture of the Philippines for providing funds to J.A.under the Next-Gen project.
文摘The development of green super rice varieties with improved nutrient use efficiency(NuUE)is a vital target area to increase yield and make it more stable under rainfed conditions.In the present study, we followed an early backcross(BC) breeding approach by using a highyielding and widely adapted Xian variety, Weed Tolerant Rice 1(WTR-1), as a recipient and a Geng variety, Hao-An-Nong(HAN), as a donor.Starting from the BC1F2 generation, the BC population went through one generation of selection under irrigated, low-input, and rainfed conditions, followed by four consecutive generations of screening and selection for high grain yield(GY) under six different nutrient conditions(NPK, 75 N,-N,-P,-NP, and-NPK), leading to the development of 230 BC1F6 introgression lines(ILs).These 230 ILs were evaluated under the same six nutrient conditions for 13 agro-morphological and grain yield component traits in comparison to four checks and parents.Significant trait variations were observed between the treatments and ILs.Positive correlations were identified for GY with biomass, panicle length, flag-leaf area, flag-leaf width, filled grain number per panicle,1000-grain weight, and tiller number under-N,-P,-NP, and-NPK conditions.Out of 230 ILs,12 were identified as promising under two or more nutrient deficiency conditions.The results demonstrated an efficient inter-subspecific BC breeding procedure with a first round of selection under rainfed-drought conditions, followed by four generations of progeny testing for yield performance under six nutrient conditions.The promising ILs can be useful resources for molecular genetic dissection and understanding the physiological mechanisms of NuUE.
文摘The primary challenge of mineland revegetation is the establishment of species able to cope with low availability of nutrients,especially in steep slopes such as of mine pits.We evaluated plant growth response and nutrient use efficiency(NUE)of two promising native Fabaceae species(Dioclea apurensis—liana from metalliferous savannas;Bauhinia longipedicellata—tree from Amazon rainforest)from the Caraja´s Mineral Province,eastern Amazon-Brazil.Plants were grown separately in 2-kg pots filled with mining waste.Substrates were fertilized with nitrogen,phosphorus,potassium(NPK),lime,and micronutrients.The results showed increments on growth of both species when nutrients were applied to the mining waste.D.apurensis showed increases in leaf area,plant height,stem diameter,and shoot dry mass production when NPK or NPK?micronutrients were applied,while B.longipedicelata was responsive to application of NPK?lime or NPK?lime?micronutrients.Further,D.apurensis showed higher NUE than B.longipedicelata,especially at the lowest doses of N,P and K.These findings may indicate a substantial advantage of D.apurensis for mineland revegetation,as this species may require lower nutrient inputs,being,therefore,a more sustainable way to revegetate degraded areas.
文摘In Saint-Louis, Senegal, a constructed wetland with horizontal flow reed beds (FHa and FHb) has demonstrated significant efficacy in treating municipal wastewater. Analyzing various treatment stages, the system showed only a slight temperature variation, from an influent average of 26.3°C to an effluent of 24.7°C. Electrical conductivity decreased from 1331 mS/cm to 974.5 mS/cm post-primary treatment, with suspended solids (SS) dramatically reduced from 718.9 mg/L to 5.7 mg/L in the final effluent. Biochemical oxygen demand (BOD5) and chemical oxygen demand (COD) saw a notable decrease, from initial levels of 655.6 mg/L and 1240 mg/L to 2.3 mg/L and 71.3 mg/L, respectively. Nitrogenous compounds (N-TN) and phosphates () also decreased significantly, indicating the system’s nutrient removal capacity. Microbiological analysis revealed a reduction in fecal coliforms from 7.5 Ulog/100ml to 1.8 Ulog/100ml and a complete elimination of helminth eggs. The presence of Phragmites and Typha was instrumental in enhancing these reductions. The system’s compliance with the Senegalese standards for disposal into natural environments, WHO recommendations for unrestricted water reuse in irrigation, and the European legislation for water reuse was established. The effluent quality met the stringent criteria for various classes of agricultural reuse, illustrating the system’s potential for sustainable water management. This wetland model presents a robust solution for water-stressed regions, ensuring environmental protection while supporting agricultural needs. The study calls for ongoing research to further refine the system for optimal, reliable wastewater treatment and water resource sustainability.
基金the project "Cash Crops Research Network of China" of the Center for Resources, Environment and Food Security, China Agricultural UniversityProfessor Oene Oenema from Alterra Wageningnen University, the Netherlands, for his financial support of the research
文摘China is in a dominant position in apple production globally with both the largest apple growing area and the largest export of fresh apple fruits. However, the annual productivity of China's apple is significantly lower than that of other dominant apple producing countries. In addition, apple production is based on excessive application of chemical fertilizers and the nutrient use efficiency (especially nitrogen) is therefore low and the nutrient emissions to the environment are high. Apple production in China is considerably contributes to farmers' incomes and is important as export product. There is an urgent need to enhance apple productivity and improve nutrient use efficiencies in intensive apple production systems in the country. These can be attained by improved understanding of production potential, yield gaps, nutrient use and best management in apple orchards. To the end, priorities in research on apple production systems and required political support are described which may lead to more sustainable and environmental-friendly intensification of apple production in China.
基金supported by the National Key Research and Development Program of China (2016YFD0100706)the National Transgenic Key Project from the Ministry of Agriculture of China (2016ZX08002-005)
文摘The success of the Green Revolution largely relies on fertilizers, and a new Green Revolution is very much needed to use fertilizers more economically and efficiently, as well as with more environmental responsibility. The use efficiency of nitrogen, phosphorus, and potassium is controlled by complex gene networks that co-ordinate uptake, re-distribution, assimilation, and storage of these nutrients. Great progress has been made in breeding nutrient-efficient crops by molecularly engineering root traits desirable for efficient acquisition of nutrients from soil, transporters for uptake, redistribution and homeostasis of nutrients, and enzymes for efficient assimilation. Regulatory and transcription factors modulating these processes are also valuable in breeding crops with improved nutrient use efficiency and yield performance.
基金the financial support of the National Key Research and Development Program of China (2016YFD0300109 and 2018YFD0200703)the National Natural Science Foundation of China (31771709)+2 种基金the Jiangsu Agricultural Industry Technology System of China (JATS[2019]458)the High-end Talent Support Program of Yangzhou University, Chinathe Priority Academic Program Development of Jiangsu Higher Education Institutions, China。
文摘Optimal planting density and proper fertilization method are important factors to improve maize yield and nutrient utilization. A two-year(2016 and 2017) field experiment was conducted with three plant densities(6.0, 7.5 and 9.0 plants m^-2) and three fertilization modes(no fertilizer, 0 F;one-off application of slow-released fertilizer, SF;twice application of conventional fertilizer, CF). Results indicated that the grain yields and N, P and K use efficiencies under SF with the optimal planting density(7.5 plants m^-2) were the highest among all the treatments in 2016 and 2017. Compared with CF, SF could increase post-silking dry matter accumulation and promote N, P and K uptake at pre-and post-silking stages;this treatment increased grain N, P and K concentrations and resulted in high N, P and K use efficiencies. Nutrient(N, P and K) absorption efficiencies and partial productivity, and nutrient(N and P) recovery efficiency in SF treatment were significantly higher than those in CF treatments under the planting density of 7.5 plants m^-2. Under both SF and CF conditions, the grain yield, total N accumulation and nutrient use efficiencies initially increased, peaked at planting density of 7.5 plants m^-2, and then decreased with increasing plant density. Based on the yield and nutrient use efficiency in two years, plant density of 7.5 plants m^-2 with SF can improve both the grain yield and N, P and K use efficiency of spring maize in Jiangsu Province, China.
基金supported by The University of Burdwan in the form of Ph.D.work(2011-12/2)
文摘We studied leaf litter fall, decomposition and nutrient release patterns of Shorea robusta and Tectona grandis by using a litter bag technique to better understand the release pattern of nutrients to soil from leaf litter. Annual litterfall varied from 13.40 ± 2.56 t ha-1 a-1 for S. robusta to 11.03 ± 3.72 t ha-1 a-1 for T. grandis and the decay constant (k) of decomposed leaf litter was distinctly higher for T. grandis (2.70 ± 0.50 a-1) compared to S. robusta (2.41 ±0.30 a-1). Biomass loss was positively correlated with the initial litter C, WSC, C/N and ash content in S. robusta and N, P and K concentration for T. grandis. Biomass was negatively correlated with lignin and L/N ratio for S. robusta and L, WSC, L/N and C/N ratio for T. grandis (P 〈 0.01). Nutrient use efficiency (NUE) and nutrient accumulation index (NAI) of S. robusta was higher than for T. grandis. The retranslocation of bioelements from senescent leaves ranked as P 〉 N 〉 K. Annual N, P and K input to soil through litterfall differed significantly between the two species in the following order: N〉K^P. S. robusta was superior in terms of K and P return and T. grandis was superior in terms of N return. The two tree species showed a similar patterns of nutrient release (K 〉 P 〉 N) during decomposition of their leaf litter.Nutrients of N, K and P were the primary limiting nutrients returned to soil through litterfall with important roles in soil fertility and forest productivity.
基金supported by the National Key Research and Development Program of China(2018YFD0201001 and 2016YFD0200102)the Kansas Agricultural Experiment Station,USA(21-079-J)。
文摘Nutrient balance is essential for attaining high yield and improving profits in agricultural farming systems,and crop nutrient uptake ratio and stoichiometry can indicate crop nutrient limitations in the field.We collected a large amount of field data to study the variations in yield,nutrient uptake and nutrient stoichiometry of peanut(Arachis hypogaea L.)in Southeast China(SEC),North-central China(NCC),and Northeast China(NEC),during 1993 to 2018.Peanut pod yield gradually increased from 1993 to 2018,with average yields of 4148,5138,and 4635 kg ha–1 in SEC,NCC,and NEC,respectively.The nitrogen(N)internal efficiency(NIE,yield to N uptake ratio)was similar among the three regions,but phosphorus(P)IE(PIE,yield to P uptake ratio)changed from low to high among regions:NCC<SEC<NEC,while potassium(K)IE(KIE,yield to K uptake ratio)portrayed a different pattern of SEC<NCC<NEC.Based on the nutrient IE,to produce 1 Mg of pod yield,the average N,P,and K requirements of the above-ground parts of peanut were roughly 47.2,5.1,and 25.5 kg in SEC,44.8,5.7,and 20.6 kg in NCC,and 44.6,4.4,and 14.7 kg in NEC,respectively.The N/P ratio changed in the sequence NCC<SEC<NEC,and the N/K ratio was similar in NEC and NCC,but lower in SEC.The N harvest index(HI)and KHI declined with increasing nutrient uptake across all regions under high nutrient uptake.The low PIE and N/P ratios in NCC could be explained by the high P accumulation in stover,and high KIE and N/K ratios in NEC may be attributed to the low soil K supply.The frontier analysis approach provides a practical framework and allows documentation of a decline in nutrient HI as nutrient uptake increases.Lastly,this study reveals the limitation and surplus of nutrients of peanut in different regions of China.
文摘This study was executed to offer the basis for optimized profit from fertilizer use for sorghum yield and to determine robust crop nutrient response function and economic rate for the production of sorghum at Miesso Central Rift Valley of Ethiopia. Trails were conducted at six experimental sites, sorghum yield response to N and P fertilizers application and economically optimum rates of nitrogen (EONR) and phosphorus (EOPR) were evaluated on a vertisols within the semi-arid Miesso districts west Hararge zone of Oromia region. The nutrient rates in 2014 cropping season four levels of Nitrogen (N) alone, these levels with 20 <span style="white-space:nowrap;">kg·ha<sup>−1</sup></span> Phosphorus (P) and without N, 69 kg<span style="white-space:nowrap;">·</span>ha<sup><span style="white-space:nowrap;">−</span>1</sup> N with three levels of P treatments including the zero control were evaluated. In 2015, cropping season similar rates of N alone, the same rate N with 20 <span style="white-space:nowrap;">kg·ha<sup>−1</sup></span> P, 92 <span style="white-space:nowrap;">kg·ha<sup>−1</sup></span> N with three rates of P including the zero control were evaluated. The treatments were arranged in a randomized complete block with three replications in factorial design. Nutrient responses of sorghum were determined using asymptotic quadratic plateau functions. The significantly highest nitrogen rate was 46 <span style="white-space:nowrap;">kg·ha<sup>−1</sup></span> alone in 2014 season, which gave grain yield of 2.56 Mg<span style="white-space:nowrap;">·ha<sup>−1</sup></span><sup> </sup>with a maximum yield advantage of 43%. P rates in both seasons and combined (sites + seasons) were not significantly influenced sorghum yield. Nitrogen agronomic and partial factor productivity peaked at 23 kg N <span style="white-space:nowrap;">ha<sup>−1</sup></span> but declined with increasing N rate. The EONR combined (sites + seasons) were 37, 45, 52 and 60 <span style="white-space:nowrap;">kg·ha<sup>−1</sup></span><sup> </sup>and for the profit to cost ratio (PCR) were 2.43, 3.65, 4.86 and 5.79 at difference cost to grain price ratios (CP) = 3.6, 2.3, 1.6 and 1.2 respectively at Miesso Ethiopia. Nitrogen application had economically profitable than P. The study concluded that the application of N at 37 or 60 kg N <span style="white-space:nowrap;">ha<sup>−1</sup></span> to sorghum production could be economically profitable for those economically constrained farmers or economically not constrained farmers. Validation should be farther conducted on farmers’ fields for refining the results obtained.
文摘Physiological characteristics of rice at different Zn^(2+) levels[pZn^(2+)>11.5, 11.3, 11.0, 10.6, 10.3, 9.7] were studied with the Zn-efficient rice cultivars IR34, IR36, IR8192, and Zn-inefficient rice cultivars IR26, Ce 64-7, Biyuzaonuo, which grew in chelator-buffered nutrient solution. There were significant differences in tolerance to zinc deficiency among different rice genotypes. Obvious effects of low zinc activity on the physiological characteristic of rice seedlings were noted. There were significant differences in chlorophyll content, photosynthesis rate, MDA concentration in rice leaf, and H^+ excretion of root. As pZn^(2+) decreased, chlorophyll content and photosynthesis rate decreased at a slower pace in Zn-efficient cultivars compared to Zn-inefficient ones, MDA concentration increased slower while H^+ excretion of root increased faster in Zn-efficient cultivars than those in Zn-inefficient ones. It was suggested that the above indications could be used as indexes to Zn-efficiency of rice.
文摘Root system architecture(RSA)plays a pivotal role in efficient uptake of essential nutrients,such as phosphorous(P),nitrogen(N),and water In soils with heterogeneous nutrient distribution,root plasticity can optimize acquisition and plant growth.Here,we present evidence that a constitutive RSA can confer benefits for sorghum grown under both sufficient and limiting growth conditions.Our studies,using P efficient SC103 and inefficient BTx635 sorghum cultivars,identified significant differences in root traits,with SC103 developing a larger root system with more and longer lateral roots,and enhanced shoot biomass,under both nutrient sufficient and deficient conditions.In addition to this constitutive attribute,under P deficiency,both cultivars exhibited an initial increase in lateral root development;however,SC103 still maintained the larger root biomass.Although N deficiency and drought stress inhibited both root and shoot growth,for both sorghum cultivars,SC103 again maintained the better performance.These findings reveal that SC103,a P efficient sorghum cultivar,also exhibited enhanced growth performance under N deficiency and drought.Our results provide evidence that this constitutive nature of RSA can provide an avenue for breeding nutrient-and drought-resilient crops.
文摘Abiotic stresses and soil nutrient limitations are major environmental conditions that reduce plant growth,productivity and quality.Plants have evolved mechanisms to perceive these environmental challenges,transmit the stress signals within cells as well as between cells and tissues,and make appropriate adjustments in their growth and development in order to survive and reproduce.In recent years,significant progress has been made on many fronts of the stress signaling research,particularly in understanding the downstream signaling events that culminate at the activation of stress-and nutrient limitation-responsive genes,cellular ion homeostasis,and growth adjustment.However,the revelation of the early events of stress signaling,particularly the identification of primary stress sensors,still lags behind.In this review,we summarize recent work on the genetic and molecular mechanisms of plant abiotic stress and nutrient limitation sensing and signaling and discuss new directions for future studies.
文摘Three diploid (Triticum boeoticum, AA; Aegilops speltoides, BB and Ae. tauschii, DD), two tetraplold (T. dlcoccoides, AABB and T. dicoccon, AABB) and one hexapioid (T. vulgare, AABBDD) varieties of wheat, which are very important In the evolution of wheat were chosen in this study. A pot experiment was carried out on the wheat under different water and nutrient conditions (i) to understand the differences in biomass, yield, water use efficiency (WUE), and nutrient (N, P and K) use efficiency (uptake and utilization efficiency) among ploidies in the evolution of wheat; (li) to clarify the effect of water and nutrient conditions on water and nutrient use efficiency; and (ill) to assess the relationship of water and nutrient use efficiency in the evolution of wheat. Our results showed that from diploid to tetraplold then to hexaploid during the evolution of wheat, both root biomass and above-ground biomass Increased Initially and then decreased. Water consumption for transpiration decreased remarkably, correlating with the decline of the growth period, while grain yield, harvest index, WUE, N, P and K uptake efficiency, and N, P and K utilization efficiency Increased significantly. Grain yield, harvest index and WUE decreased In the same order: T. vulgare 〉 T. dicoccon 〉 T. dicoccoides 〉 Ae. tauschii 〉 Ae. speltoides 〉 T. boeoticum. Water stress significantly decreased root blomass, above-ground biomass, yield, and water consumption for transpiration by 47-52%, but remarkably Increased WUE. Increasing the nutrient supply increased wheat above-ground biomass, grain yield, harvest Index, water consumption for transpiration and WUE under different water levels, but reduced root blomass under drought conditions. Generally, water stress and low nutrient supply resulted in the lower nutrient uptake efficiency of wheat. However, water and nutrient application had no significant effects on nutrient utilization efficiency, suggesting that wheat nutrient utilization efficiency is mainly controlled by genotypes. Compared to the other two diploid wheats, Ae. squarrosa (DD) had significant higher WUE and nutrient utilization efficiency, Indicating that the D genome may carry genes controlling high efficient utilization of water and nutrient. Significant relation- ships were found between WUE and N, P and K utilization efficiency.
文摘We conducted a study to find out if arbuscular mycorrhizal(AM) fungi(Acaulospora scrobiculata,Scutellospora calospora) and phosphate solubilizing bacteria(PSB, Paenibacillus polymyxa) inoculation either individually or in combinations can improve Acacia auriculiformis seedling growth, uptake of nutrients and quality in a phosphorus deficient tropical Alfisol. The seedlings were assessed for various growth and nutrient uptake parameters after 60 days of treatment. Inoculation with P.polymyxa stimulated mycorrhizal formation. Seedling height, stem girth, taproot length, number of leaves and leaf area, plant dry matter production, nodulation, and nodular dry weight were significantly higher for seedlings that were either dual inoculated or triple inoculated compared to individual inoculation of AM fungi or PSB, and uninoculated seedlings. Dual and triple application of AM fungi and PSB also significantly improved the nutrient contents of shoots and roots and nutrient uptake efficiencies. The calculated seedling quality indexes of the AM fungi and PSB inoculated seedling were 25–208% higher than uninoculated seedlings. These findings show that A.auriculiformis seedlings when dual inoculated or triple inoculated performed better than seedlings inoculated with the microbes individually and compared with uninoculated control seedlings. We conclude that bioinoculation is important for the production of high-quality A.auriculiformis seedlings in tree nurseries for planting in nutrient deficient soils.
文摘Teak (Tectona grandis Linn. f.) ranks among the top five tropical hardwood species and is being promoted for use in plantations in its non-native range due to its high economic value. However, there is a general lack of data on ecosystem functioning of teak plantations. We aimed at understanding storage and flux of nutrients related to young plantations of teak. Cycling of nitrogen (N) and phosphorus (P) in a chronosequence of plantations (1, 5, 11, 18, 24 and 30 years) was studied in the Moist Deciduous Forest Region of North India with the objective of investigating the nutrient cycling pattern at younger age since the current trend of harvesting age of the species in several tropical countries is being drastically reduced for quick return from this high value crop. Standing state, nutrient uptake, nutrient return and nutrient retransloca-tion in these plantations were estimated by tree harvesting and chemical analysis methods. The range of total standing nutrient across all these plantations was 20.3 to 586.6 kg?ha-1 for N and 5.3 to 208.8 kg?ha-1 for P. Net uptake of N ranged from 19.4 to 88.9 kg?ha-1?a-1 and P from 3.8 to 18.1 kg?ha-1?a-1. Retranslocation of N and P among all the stands ranged from 8.7 to 48.0 kg?ha-1?a-1 and 0.01 to 3.5 kg?ha-1?a-1, respectively. Range of total nutrient return was 25.8 to 91.3 kg?ha-1?a-1 for N and 2.7 to 10.1 kg?ha-1?a-1 for P. N and P use efficiency was between 107.4 and 192.5 g dry organic matter (OM) g-1N, and 551.9 and 841.1 g OM g-1P, respec-tively. The turnover time ranged from 2.04-13.17 years for N and be-tween 2.40-22.66 years for P. Quantity of N and P in the soil nutrient pool ranged from 2566.8 to 4426.8 kg?ha-1 and 372 to 520 kg?ha-1, re-spectively. Storage and flux of components in different plant parts of different aged plantations were assessed and depicted in compartment models. Percentage storage in soil, litter and vegetation ranged from 82% to 99%, 0.6% to 2.4% and 0.5% to 15% for N, respectively, and from 63% to 98%, 0.5% to 2% and 1% to 35% for P, respectively. This infor-mation could be useful in managing external nutrient manipulation to crops of different ages for optimum biomass production or carbon se-questration.
基金This research was supported by National Natural Science Foundation of China(41806168)Agriculture Research System of China(CARS-50)+2 种基金Start-Up funding of Shantou University(NTF18004)Department of Education of Guangdong Province(2017KQNCX076)International cooperation research project of Shantou University(NC2017001).
文摘Given the central role of light in the algal photosynthesis,respiration,cell division,growth and the accumulation of value products,the effects of light-emitting diodes(LEDs)light wavelengths(blue,white,red and green)were studied in Scenedesmus obliquus.Biomass,residual nutrient amount,soluble protein,astaxanthin and reactive oxygen species,superoxide dismutase(SOD),catalase(CAT)and peroxidase(POD)activity were analyzed to determine the effects of different monochromatic light wavelengths via biochemical methods.The results showed that blue light wavelength is the optimal light wavelength for phosphorus removal efficiency and the accumulation of biomass and astaxanthin in S.obliquus.Meanwhile,high reactive oxygen species content under the blue light might induce the accumulation of astaxanthin.The high activity of SOD,CAT and POD might participate in clearing the reactive oxygen species to facilitate the growth of microalgae.Furthermore,we found mixed blue/green lights treatment is the most appropriate mixture for the nitrogen removal.Under the blue light treatment,high light intensity and 18L:6D light cycle is the best condition for biomass and astaxanthin accumulation.Optimal nitrogen/phosphorus removal efficiency was observed under a 24L:0D light cycle.These results might provide a foundational data for the optimizing the productivity of high-value metabolites and treatment of wastewater.
基金Guangxi Key R&D Program(GuiKe AB18221027)Guangxi Natural Science Foundation(2018GXNSFAA281027)Basic Scientific Research Program of Guangxi Academy of Agricultural Sciences(2020YM110,2021YT036).
文摘[Objectives]To systematically study the effects of different nitrogen levels on the growth and nitrogen utilization of sugarcane in Guangxi.[Methods]Through field experiment and indoor analysis,different nitrogen application levels were set up to determine soil nitrogen content and sugarcane nitrogen content.The effects of different nitrogen levels on sugarcane yield,agronomic characters and nitrogen utilization were studied.[Results]The effect of nitrogen application rate on sugarcane yield showed a quadratic curve,and nitrogen application could significantly increase sugarcane yield,and the sugarcane yield reached the maximum when the nitrogen application rate reached 714 kg/ha.[Conclusions]With the increase of nitrogen application rate,sugarcane yield increased,but when it exceeded a certain range,the sugarcane yield decreased significantly.