Effect of Different Arbuscular Mycorrhizal Fungi Strains on Mineral Nutrition and Antioxidant Enzymes of Chrysanthemum morifolium

[Objective] The purpose was to study the effects of different arbuscular mycorrhizal fungi strains（AMF）on the mineral nutrition and antioxidant enzymes of Chrysanthemum morifolium.[Method] The pot experiment was conducted in the greenhouse,C.morifolium ＇Jinba＇ was inoculated with five kinds of AMF,N,P,K,malondial dehyde（MDA）content,as well as the superoxide dismutase（SOD）,peroxidase（POD） and catalase（CAT） activity in roots,leaves and petals of C.morifolium were measured at seedling and flowering stages.[Result] The G.i,G.e and G.m treatments could promote mineral nutrient absorption,increase N,P,K content in roots,leaves and petals of C.morifolium compared with the control without inoculation.The G.d、G.e and G.m treatments could significantly reduce MDA content in roots and petals,thus alleviating membrane permeability and lipid peroxidation.The G.i treatments could also improve the SOD,POD and CAT activities of C.morifolium,thereby increasing the capability of scavenging oxygen free radicals.[Conclusion] According to the comprehensive analysis,G.i was screened out as the best strain to improve mineral nutrition and antioxidant enzyme activities of C.morifolium.

Effects of Seedling-cake Integrated with Arbuscular Mycorrhizal Fungi on Resistance of Bacterial Wilt in Pepper (Capsicum annuum L.)

[Objective] The aim was to investigated the effects of seedling-cake with AMF on resistance of pepper （Capsicum annuum L.） to bacterial wilt. [Methods] A pot experiment was conducted to evaluate the dynamics of mycorrhizal colonization, disease index, morbidity rate, control effect and several agronomic traits of mycorrhizal seedlings after inoculation with RS in two kinds of seeding-cakes with AMF. [Results] Two kinds of seedling-cakes formed steadily mycorrhizal colonization after inoculation, which enhanced disease-resistance and decreased morbidity rate and disease index in different degrees. What’s more, the performance of self-made seedling-cakes was obviously better than that of commercial seedling-cakes. [Conclusions] Self-made seedling-cakes with AMF have superior performance on bacterial wilt resistance of pepper, which should be made use of in other crops extensively.

海南省统一战线服务科学发展实践基地揭牌

"海南省统一战线服务科学发展实践基地"揭牌暨第一批项目启动仪式日前在琼中黎族苗族自治县营根中学举行。

刊中报

西双版纳垦区2003年橡胶干胶总产量10.8万吨 2002年,云南西双版纳垦区橡胶干胶总产10.4万吨,首次突破10万吨。2003年该垦区干胶生产又有新增长,总产10.8万吨,比上年增产4000余吨,实现再过10万吨的目标。 该垦区2003年橡胶生产的气候和物候条件虽然不如2002年,相比开割时间晚,停割时间早,却仍然实现了生产总量的增长,其直接原因有三,一是经营政策调动,推行职工岗位承包、家庭经营的改革政策。

Effects of Nutrient Solution pH on the Growth of Seedlings of Sugarcane

The impacts of pH on roots growth of sugarcane seedlings were explored by a pot test. The nutrient solution with three pH levels, Le., 5.0, 7.0 and 8.5 were applied to culture five combination seedlings, including A （RB85-5156 × YR05-407）, B （YR06-3501 ×Tolodo）, C （YT94-128 × GZ75-65）, D （ROC6 × YR05-733） and E （VMC87-95 ×YR05-171）. The result indicated that root length, root surface, root volume and root diameter were all in the largest in B combination with solution pH= 7.0, and the root length, root surface, root volume were in the largest in combination A, C, D and E with solution pH=8.5. Root activity in combination C, D and E were in the highest with solution pH=5.0, while it was in the highest for combination B when pH=7.0. In general, the root growth and morphology in all five combinations were better in the solutions with pH of 7.0 and 8.5.

Effect of Potassium and Moisture on Rape Growth and Its Nutrient Uptake

The Interaction between potassium and moisture during the growth of and nutrient uptake by rapeseed plants grown on K-deficient soils has been investigated in this Study. The results show that the dry weight of the above-ground parts of the plant appears to be somewhat reduced when the volume water content of the soil remains 0.15 for 3 successive days. As the shortage in the soil water continues, the height of the plant root and the permeability of the root plasmalemma are markedly affected; the stem thickness and leaf area are reduced. However, K application can increase the dry matter weight of the above-ground parts, the thickness of the stem, and the area of the leaf. Application of K can also maintain a comparatively low water potential(ψ) and a comparatively high moisture content in the leaves, thus increasing the drought-resisting ability of the plant. When the volume water content of the soil is raised to 0.30, leaf yellowing as a symptom of nutrient deficiency appears on rapeseed plants grown on K-deficient soils. With increase in soil moisture content, the Ca concentration of the aerial parts of the rapeseed plant without K application increases while the K concentration decreases. Both K application and the soil moisture regime have very little effect on the Mg concentration in the plant. Under soil moisture stress, the nitrogen content and total amount of alnino acids in rape leaves increases; and thus more proline and glutamic acid is formed. On the other hand, the impact of soil moisture on plant's dry matter is governed by the status of potassium nutrition. On soils with low K, the moisture content has very little effect on yield; when K fertilizer is applied, however, the moisture content shows a very significant effect on yield increase.

Influences of Root Zone Restriction and Nitrogen Nutrition on Hybrid Wheat Growth

To study the physiological effects of small root zonel plants of a hybrid wheat variety (Triticum aestivnmL.cv. Meiyou 4) were grown in small pots (1 litre) or large pots (8 litre) with 1ow nitrogen (50 mg kg-1 soil)and high nitrogen (200 mg kg-1 soil). Restricting root zone decreased dry weight of plants at the stages ofstem elongation and flowering, compared to those of control plants grown in the large pots (P<0.01). Sprayingof 6-benzylaminopurine (50 μmol L-1) increased dry weight of plants and chlorop hyll concentration in leaves.Restriction of root zone decreased the concentrations of total nitrogen, chlorophyll and soluble protein in thefiag leaf and acce1erated senescence of the leaves. Supply of high nitrogen delayed senescence of the fiag leafThe results suggested that the shortage of nutrients, especially nitrogen deficiency was the primary reasonfor the decreased growth of plant in the treatment of root zone restriction.

Effect of Different Organic Nutrient Sources and Two NPK Rates on the Performance and Nutrient Contents of A Newly Released Cassava Variety

A field experiment was conducted to determine the response of a newly released cassava variety （TMS 98/0510） in Nigeria to three sources of organic manure （poultry waste, pig dung and goat dung at 10 t/ha）, two levels inorganic fertilizer （N：P：K 15：15：15 at 200 and 400 kg/ha） and a control treatment. The six treatments were compared in a randomized complete block design with three replications. Data were collected on yields and yield related agronomic and morphological traits. Data were also collected on soil nutrient content at planting and the content of N, P, K, Ca and Mg in the leaf stem and roots. The results showed that the soil used in this experiment was low in organic matter and other nutrients except available P. Inorganic and organic fertilizers significantly increased leaf area, however yield and growth related traits like plant height, number of leaves, stem yield, tuber girth, number of roots and harvest index were not significantly different among the treatments. Contrary to expectations manure and fertilizer treatments did not increase fresh root yield in this cassava variety. They did not also influence the content of N, P, K, Ca and Mg in the stem, leaf and root. This response suggests that cassava varieties bred for farmers＇ conditions in Nigeria, which are inherently low in soil nutrients, may not respond to additional nutrient input. Breeders should therefore select cassava for dual adaptation to low and high nutrient levels in the soil to meet the needs of a wider spectrum of farmers and to justify government and extension support for the use of input by farmers in Nigeria.

Effects of Spraying Plant Nutrient, Slaked Lime and Pokeberry Root Powder on Cadmium Reduction in Rice

The pot experiment was carried out in this study to further explore the impact of plant nutrient, slaked lime, pokeberry root powder on cadmium （Cd） absorption by rice, and to screen practical agronomic measures which could reduce the accumulation of cadmium. In the control treatment nothing but water was sprayed into rice, while in other treatments, plant nutrient, slaked lime and pokeberry root powder were sprayed on rice at the tillering stage, the heading stage and the dough stage, respectively. The plant samples and soil samples were collected after the harvest and then analyzed on aimed indexes. The results showed that Cd contents in rice plants were significantly decreased, total Cd contents in brown rice were significantly （P〈0.05） decreased after rice was sprayed with plant nutrient, slaked lime and pokeberry root powder at different growing stages. However, while rice was sprayed with the three materials all at the tillering stage, the heading stage and the dough stage, the total Cd contents in brown rice were decreased by a maximum reduction that was 53.4% to 57.5% below that of the control, which was signifcantly （P〈0.05） lower than other treatments. Meanwhile, the biggest reduction of Cd inrice sprayed with the three materials at the tillering stage was 19.6% to 35.1% below that of the control, which was signifcantly （P〈0.05） lower than other treatments. In conclusion, spraying plant nutrient, slaked lime and pokeberry root powder on rice at different growing stages could not only reduce the absorption accumulation of Cd by root system, but also change the activities of rice and physical and chemical properties of soil, and then inhibit the absorption of Cd by the root system and the transfer of Cd in the rice plant. Therefore, the multiple factors may be the main causes of reducing Cd contents in the brown rice when the three materials are sprayed on rice at different growing stages.

Effect of Manure on Distribntion of Micronutrients in Rhizosphere of Wheat

A rhizobox system was used to determine the distribution of micronutrients (Fe, Mn, Cu and Zn) acrossthe rhmosphere of wheat (Triticum aestivum). The available contents of Fe and Mn in the rhizosphere wereraised by addition of manure or chemical fertilizer combined with manure, but those of Cu and Zn werehardly affected, which might be an important reason why manure addition could improve the Fe and Mnnutrition status of plants. Several possible mechanisms for the increase of the availabilities of Fe and Mn inthe rhizosphere due to manuring are discussed as well.

Phosphorus fertilizer induced changes in the soil available P,the P nutrition and the growth of Pinus radiata seedlings grown in association with understory

A study was carried out to investigate changes in the soil plant-available P,the P nutrition and the growth of Pinus radiata seedlings grown in association with understory,broom（Cytisus scoparius L.） or ryegrass（Lolium multiflorum） on Orthic Allophanic Soil,following the application of three rates of triple superphosphate（TSP）（0,50,and 100 mg·kg^-1P） under a glasshouse condition.The application of P fertilizer enhanced P availability in the rhizospheric of radiata seedlings and the bulk soils in a P-deficient site.P availability in the rhizospheric soils of ryegrass and broom,grown in association with radiata,were also increased by the presence of radiata roots.P concentrations in new shoot needles,old shoot needles,stem and roots of radiata pine increased with increase rates of TSP application,but the effects of ryegrass and broom on P nutrition of radiata seedlings depended on the soil P status.In the absence of P fertilizer addition（control treatment）,P concentrations in new shoot needles,old shoot needles,stem,and roots of radiata grown in association with broom were higher than those with ryegrass,whereas,when P fertilizer was added（50 and 100 mg·kg^-1） the P concentration was lower.This is probably related to the growth of broom that may have removed much of the plant-available P in the soil as indicated by the consistently lower Bray-2 P concentration in the rhizosphere soil of radiata in association with broom than that in the rhizosphere soil of radiata in association with grass at the two high P rates.Furthermore,in the high P fertile soil（application rate of 100 mg·kg^-1）,the dry matter yield of radiata was lower when it was grown with broom than with ryegrass.This result suggests that in moderate to high P fertile soils,P.radiata seedlings grow better with ryegrass than with broom,because broom grows vigorously in high P fertile soil and competes with P.radiata for P and perhaps for other nutrients as well.

Plant Enzymes, Root Exudates, Cluster Roots and Mycorrhizal Symbiosis are the Drivers of P Nutrition in Native Legumes Growing in P Deficient Soil of the Cape Fynbos in South Africa

The Cape fynbos is characterised by highly leached, sandy, acidic soils with very low nutrient concentrations. Plant-available P levels range from 0.4 μg P g-1 to 3.7 μg P g-I soil, and 1-2 mg N gl soil. Despite these low nutrient concentrations, the fynbos is home to 9,030 vascular plant species with 68.7% endemicity. How native plant species survive such low levels of available P is intriguing, and indeed the subject of this review. In the fynbos soils, P is easily precipitated with cations such as Fe and Al, forming AI-P and Fe-P in acidic soils, or Ca-P in neutral-to-alkaline soils. The mechanisms for promoting P availability and enhancing P nutrition include the development of mycorrhizal symbiosis （with 80%-90% of higher plants, e.g., Cyclopia, Aspalathus, Psoralea and Leucadendron etc.） which exhibits 3-5 times much greater P acquisition than non-mycorrhizal roots. Formation of cluster roots by the Leguminosae （Fabaceae） and their exudation of Kreb cycle intermediates （organic acids） for solubilizing P, secretion of root exudate compounds （organic acids, phenolics, amino acids, etc.） that mobilize P. The synthesis and release of acid and alkaline phosphatase enzyme that catalyze the cleavage of mineral P from organic phosphate esters in acidic and alkaline soils, and the development of deep tap roots as well as massive secondary roots within the uppermost 15 cm of soil for capturing water and nutrients. Some fynbos legumes employ all these adaptive mechanisms for enhancing P nutrition and plant growth. Aspalathus and Cyclopia species typically form mycorrhizal and rhizobial symbiosis for improving P and N nutrition, produce cluster roots and acid phosphatases for increasing P supply, and release root exudates that enhance P solubilisation and uptake.

Effect of Spraying Liquorices Root Extract on Vegetative Growth, Chemical Characters and Photosynthetic Pigments of Chrysanthemum （Chrysanthemum morifolium L.） Grown under Salt Stress

This experiment was conducted in Horticulture Department, School of Plant Production, Faculty of Agriculture and Forestry, University of Duhok, Iraq in 2010 on Chrysanthemum plants, in order to mitigate the adverse influence of salinity by the use of liquorice root extract and study its effect on vegetative growth, chlorophyll content in leaves from chlorophyll and assistant pigment, carbohydrate and starch. Subsequently, the trail consisted of three levels of salinity （0, 4 and 8 ds m^-1） and three concentrations of the liquorice root extract 0, 2.5 and 5 g L^-1. Results showed that salinity （4 ds m^-1） rate caused significant increases in certain vegetative characteristics （branches number, plant height, leaves number and leaf area）, photosynthetic pigments （Chl a, Chl b, total chlorophyll, a-carotene, β-carotene, zeaxanthin, astaxanthin）, fresh shoot weight, fresh root weight, shoot dry weight, root dry weight, shoot： root ratio, carbohydrate dry weight percentage and starch percentage as compared to untreated check. However, increasing salinity rate to 8 ds m^-1 resulted in substantial reductions in all above mentioned Waits. Treatment with liquorices root extract, in particular, 5 g L^-1 manifested a potent capability in ameliorating the salinity negative effects in terms of vegetative and photosynthetic pigments aspects.

Isolation of Six Phosphate Dissolving Rhizosphere Bacteria （Bacillus subtilis） and Their Effects on the Growth, Phosphorus Nutrition and Yield of Maize （Zea mays L.） in Mali

The disadvantages of the long term application of Tilemsi natural phosphate （TNP） on maize （Zea mays L.） production has come out because of its low P availability. Some functional soil microbes, such as phosphate dissolving bacteria, have great potential in improvement of P solubility from TNP and P uptake by plants. The present study aimed to isolate and characterize typical phosphate dissolving bacterial strains （Bacillus subtilis） from Malian soils, and investigate their role in P uptake by maize grown in soils amended with TNP. The experimental design was a split plot with three main plots of fertilizers sources, i.e., natural phosphate, commercial fertilizer and without fertilizer, and with seven sub-plots of six microorganisms plus the control. The field experiment results have shown that the maize inoculated with the phosphate dissolving bacteria was improved in seed germination, plant growth, plant production （increase yield by 42%）, grain and aerial dry biomass （P） content of 34% and 64%, respectively. They have also shown that the locally available TNP can be used by the Malians farmers in maize culture and have comparable production to the one obtained with the costly imported commercial phosphate fertilizer, like the complex cereal. The project has provided information for the combined use of the Mali TNP and phosphate dissolving bacteria Bacillus subtilis subsp, subtilis （T）： DSM 10 in improvement of maize production in the country.

Unit Root Analysis of Traffic Time Series in Toll Highways

Concession contracts in highways often include some kind of clauses （for example, a minimum traffic guarantee） that allow for better management of the business risks. The value of these clauses may be important and should be added to the total value of the concession. However, in these cases, traditional valuation techniques, like the NPV （net present value） of the project, are insufficient. An alternative methodology for the valuation of highway concession is one based on the real options approach. This methodology is generally built on the assumption of the evolution of traffic volume as a GBM （geometric Brownian motion）, which is the hypothesis analyzed in this paper. First, a description of the methodology used for the analysis of the existence of unit roots （i.e., the hypothesis of non-stationarity） is provided. The Dickey-Fuller approach has been used, which is the most common test for this kind of analysis. Then this methodology is applied to perform a statistical analysis of traffic series in Spanish toll highways. For this purpose, data on the AADT （annual average daily traffic） on a set of highways have been used. The period of analysis is around thirty years in most cases. The main outcome of the research is that the hypothesis that traffic volume follows a GBM process in Spanish toll highways cannot be rejected. This result is robust, and therefore it can be used as a starting point for the application of the real options theory to assess toll highway concessions.

A New Host for Meloidogyne incognita （Kofoid ＆ White 1919） Chitwood, 1949 （Nemata： Tylenchida） in Turkey： Potato

Potato is the main material of nutrition comes after the wheat and, is subjected to attacks of different plant parasitic nematodes which cause serious damages in our country. Especially, root-knot nematodes cause serious crop losses on them. Due to usage oflnfested seeds, parasitic nematodes are increasing from year to year. In our country, so far, many infested hosts of Meloidogyne incognita （Kofoid ＆White, 1919） Chitwood, 1949 were detected but there is no report on investigation on potato. During this study, adult females of root-knot nematodes were obtained via extracting gals of 133 tuber samples, collected potatoes fields in the Marmara region especially Balikesir, Bilecik, Bursa, Canakkale, Edirne, Istanbul, Kirklareli, Kocaeli, Sakarya and Tekirdag provinces during 2007-2008. During identification the species, second stage larvae were taken into consideration as well as genital preparations of adult females. For the identification classical methods were used together with molecular methods. As result, M. incognita was detected, only species detected among the Meloidogyne genus upon the 10 provinces investigated in Edirne province, Bosna village. This is the first report of the infestation of this species potato and also in Marmara Region.

Contribution of Root Proliferation in Nutrient-Rich Soil Patches to Nutrient Uptake and Growth of Maize

Root proliferation can be stimulated in a heterogeneous nutrient patch; however, the functions of the root proliferation in the nutrient-rich soil patches are not fully understood. In the present study, a two-year field experiment was conducted to examine the comparative effects of localized application of ammonium and phosphorus (P) at early or late stages on root growth, nutrient uptake, and biomass of maize (Zea mays L.) on a calcareous soil in an intensive farming system. Localized supply of ammonium and P had a more evident effect on shoot and root growth, and especially stimulated fine root development at the early seedling stage, with most of the maize roots being allocated to the nutrient-rich patch in the topsoil. Although localized ammonium and P supply at the late stage also enhanced the fine root growth, the plant roots in the patch accounted for a low proportion of the whole maize roots in the topsoil at the flowering stage. Compared with the early stage, fine root length in the short-lived nutrient patch decreased by 44%-62% and the shoot dry weight was not different between heterogeneous and homogeneous nutrient supply at the late growth stage. Localized supply of ammonium and P significantly increased N and P accumulation by maize at 35 and 47 days after sowing (DAS); however, no significant difference was found among the treatments at 82 DAS and the later growth stages. The increased nutrient uptake and plant growth was related to the higher proportion of root length in the localized nutrient-enriched patch. The results indicated that root proliferation in nutrient patches contributed more to maize growth and nutrient uptake at the early than late stages.

The sexual dimorphism displayed by the roots of mulberry(Morus alba)saplings depends on the sex of the neighboring plants

Aims Dioecious plants present sexual dimorphism,but how the root traits and nutrient uptake of female and male plants in dioecious species response to the sexual identity change of the neighbor plants are poorly understood.Methods Mulberry(Morus alba L.),a dioecious plant widely distributed in China,was employed in our study.Male and female plants were grown with neighbors of the same and opposite sex for 3 months.At harvest,the root anatomy,root morphology,nutrient concentrations and biomass accumulation were measured.Important Findings When grown with the opposite sex,the males showed decreases in root xylem size,biomass of root and stem and increases in root N,P and K concentrations compared with grown with the same sex.By contrast,females showed significant increases in xylem size,fine root system(e.g.fine root length,root surface area and root volume),root carbon isotope composition(δ13C)and root N,P and K concentrations.The changes in theδ13C and N,P and K concentrations in male and female plants were associated with the changes of root traits.These results demonstrated that the sexual identity of the neighboring plants affected root anatomy and morphology of female and male mulberry plants.Meanwhile,the responses of female and male plants to the sex change of the neighboring plants showed sexual dimorphism,which influenced water-use efficiency and resource acquisition.These findings are important for understanding the population dynamics of other dioecious species in forestry and natural systems.