[Objective] studying the influences of different UV-B radiation treatments in short time on some physiological characteristics of winter wheat seedlings was to provide reference for the mechanism of plant response to ...[Objective] studying the influences of different UV-B radiation treatments in short time on some physiological characteristics of winter wheat seedlings was to provide reference for the mechanism of plant response to ultraviolet irradiation in short time. [Method] The winter wheat taken as materials were treated with 15 and 30 pW/cm^2 UV-B radiation, then the physiological indexes such as pigment content and photosynthetic rate were determined. [ Results] The UV-B treatment caused the declines of chlorophyll content, soluble protein content and water content of leaves, besides, dose-effect was existed. The decline of 30 pW/cm^2 treatment was bigger than that of 15 μW/cm^2 treatment. The influences of UV-B radiation on carotenoid content and anthocyanidin content were similar; the change trends were declined firstly then increased. The UVB treatment with two doses restrained the electron transport of PSⅡ, particularly; the inhibitory effect was biggest after treated 2 h, and then this effect was declined in 4, 6 and 8 h, so the dose-effect was existed. The UV-B radiation with two doses restricted photosynthetic rate and the inhibitory effect increased with the increase of treatment time. The high dose treatment caused huge damage to membrane system, while the result of low dose treatment was not obvious. [ Conclusion] UV-B radiation treatment had dose-effect on winter wheat seedlings in short time and the influence of high dose was bigger than that of low dose. With the increase of treatment time, the damage was alleviated; besides, the result was not similar to that of UV-B radiation in long time.展开更多
New lines of wheat ( Triticum aestivum L.) was obtained by introducing the DNA of sorghum (Sorghum vulgare Pers.) into wheat cultivar 'Longchun 13'. The changes of respiratory pathway, contents of protein, Na+...New lines of wheat ( Triticum aestivum L.) was obtained by introducing the DNA of sorghum (Sorghum vulgare Pers.) into wheat cultivar 'Longchun 13'. The changes of respiratory pathway, contents of protein, Na+ and K+ in the leaves and roots of the new lines of wheat under salt stress were determined and compared with the control cultivar, 'Longchun 13'. The decrease of the content of K+ was observed with the increase of NaCl concentrations, but the decrease was more in the control than that in the new lines, and more in roots than in leaves. Content of proline and Na+ in both two wheats lines increased greatly, but the former increased more significantly in the new lines and the latter more significantly in control both in leaves and roots. The operation of the cyanide-resistant pathway of respiration was enhanced at different degrees after salt stress and it increased much more in roots and leaves of the control plant than that in the new lines, but the cytochrome pathway of electron transport was still the main one consistently. The possible significance of these changes was discussed.展开更多
[ Objective] The study aimed to reveal the effects of hypergravity on salt tolerance of wheat seedlings. [ Method ] The seed germination rate (Gr) and germination index (Gi) of wheat seedlings were measured under ...[ Objective] The study aimed to reveal the effects of hypergravity on salt tolerance of wheat seedlings. [ Method ] The seed germination rate (Gr) and germination index (Gi) of wheat seedlings were measured under hypergravity of 600 × g or 1 000 × g for 4 h and under the stress of 0.4% or 0.9% salt solution. The catalase (CAT) activity and malondialdehyde (MDA) content of wheat seedlings were also measured under 0.4% salt stress. [Result] Compared with seedlings in CK group (no hypergravity or salt stress), the Gr and Gi of the seedlings in salt stress treatment decreased to different extents; while the Gr and Gi of the seedlings in treatment group (hypergravity and salt stress) increased compared with that in salt stress group. CAT in seedlings of hypergravity treatment was higher than that of CK group and 0.4% salt treatment group, meanwhile the MDA showed an opposite result. [ Conclusion] Hypergravity could enhance the salt resistance of wheat in specific range, and hypergravity of 600 × g for 4 h performed better than that of 1 000 ×g for 4 h.展开更多
A knowledge model with temporal and spatial characteristics for the quantitative design of a cultural pattern in wheat production, using systems analysis and dynamic modeling techniques, was developed for wheat manage...A knowledge model with temporal and spatial characteristics for the quantitative design of a cultural pattern in wheat production, using systems analysis and dynamic modeling techniques, was developed for wheat management, as a decision-making tool in digital farming. The fundamental relationships and algorithms of wheat growth indices and management criteria to cultivars, ecological environments, and production levels were derived from the existing literature and research data to establish a knowledge model system for quantitative wheat management using Visual C^++. The system designed a cultural management plan for general management guidelines and crop regulation indices for timecourse control criteria during the wheat-growing period. The cultural management plan module included submodels to determine target grain yield and quality, cultivar choice, sowing date, population density, sowing rate, fertilization strategy, and water management, whereas the crop regulation indices module included submodels for suitable development stages, dynamic growth indices, source-sink indices, and nutrient indices. Ewluation of the knowledge model by design studies on the basis of data sets of different eco-sites, cultiwrs, and soil types indicated a favorable performance of the model system in recommending growth indices and management criteria under diverse conditions. Practical application of the knowledge model system in comparative field experiments produced yield gains of 2.4% to 16.5%. Thus, the presented knowledge model system overcame some of the difficulties of the traditional wheat management patterns and expert systems, and laid a foundation for facilitating the digitization of wheat management.展开更多
The aim of this work was to study the reactions of wheat (T. aestivum L.) and its wild congeners under salt stress. Physiological mechanisms that underlie traits for salt tolerance plantlets have been used to test s...The aim of this work was to study the reactions of wheat (T. aestivum L.) and its wild congeners under salt stress. Physiological mechanisms that underlie traits for salt tolerance plantlets have been used to test some wheat species and to identify sources of salty tolerance. Stress conditions were founded by means of exposure of the plantlets in NaCI water solution, 1.68% that demonstrably differentiates the samples by growth parameters. Under laboratory conditions the ability of seedlings to bear a significant shortage of water, their ability to accumulate biomass, changing the parameters of linear growth processes and changes in water content in leaves and roots of seedlings under stress was determined. Interest is also the rate of growth of root fibrils in saline conditions. These experiments allowed to provide a comprehensive diagnosis of studied forms of wheat and make an initial opinion on their salt tolerance. Different features of abiotic stress responses of some wheat species at the early stages of development were shown that testifies necessi~ of great number of approaches at selection of genetic material for improvement of modern wheat eultivars. This work is the first phase of research for practical breeding.展开更多
Wheat straw biodegradability during anaerobic digestion was improved by treatment with potassium hydroxide (KOH) to decrease digestion time and enhance biomethane production and fertility value. KOH concentrations o...Wheat straw biodegradability during anaerobic digestion was improved by treatment with potassium hydroxide (KOH) to decrease digestion time and enhance biomethane production and fertility value. KOH concentrations of 1% (KI), 3% ([(2), 6% (K3) and 9% (l(4) were tested for wheat straw pretreatment at ambient temperature with a C:N ratio of 25:1.86% of total solids (TS), 89% of volatile solids (VS) and 22% of lignocellulose, cellulose and hemi- cellulose (LCH) (22%) were decomposed effectively with the wheat straw pretreated by 6% KOH. Enhanced bio- gas production and cumulative biomethane yield of 258 ml. (g VS)-1 were obtained increased by 45% and 41% respectively, compared with untreated wheat straw. Pretreated wheat straw digestion also yielded a digestate with higher fertilizer values potassium (l 38%), calcium (22%) and magnesium (16%). These results show that TS, VS and LCH can be effectively removed from wheat straw pretreated with KOH, improving biodegradability biomethane production and fertilizer value.展开更多
Proline has been proposed to be an osmoprotector and scavenger of reactive oxygen species in plants subjected to water deficit. The aim of this work was to study the effects of drought on each wheat phenological stage...Proline has been proposed to be an osmoprotector and scavenger of reactive oxygen species in plants subjected to water deficit. The aim of this work was to study the effects of drought on each wheat phenological stage (tillering, booting, heading, flowering and grain-filling) using stress parameters such as the relative water content (RWC), membrane stability index (MSI), lipid peroxidation through malondialdehyde levels (MDA) and determination of proline content (PRO). The Brazilian commercial elite cultivar Triticum aestivum cv. CD 200126 was submitted to eight days of water deficit stress at each stage. The perception of stress was low at tillering and high at the final stages of growth, as verified by the reduction in the MSI and RWC. However, an increase in the MDA was clearly observed. We observed a high proline accumulation when stress was applied, although it was not sufficient to prevent damages. These results indicate that the relevant stages to evaluate the effect of water shortage during wheat plant development are booting, heading and flowering.展开更多
Pakistani wheat varieties are grown over a wide agro-climatic range and as such are anticipated to exhibit yield and quality differences. It is therefore necessary to investigate the nutritional status of wheat variet...Pakistani wheat varieties are grown over a wide agro-climatic range and as such are anticipated to exhibit yield and quality differences. It is therefore necessary to investigate the nutritional status of wheat varieties in terms of biochemical and physiochemical characteristics available for food and nutritional purposes in Pakistan. The result shows that wheat grains of different varieties contain a net protein level of 9.15%~10.27%, 2.15%~2.55% total fats, 1.72%~1.85% dietary fibers, 77.65×10-6~84.25×10-6 of potassium and 7.70×10-6~35.90×10-6 of sodium ions concentration, 0.24×10-6~0.84×10-6 of phosphorus, 1.44%~2.10% ash, 31.108~43.602 g of thousand grain mass (TGM) and 8.38%~9.67% moisture contents. This study is significant in providing an opportunity to explore the available wheat varieties and to further improve their nutritional excellence and also essential for setting nutritional regulations for domestic and export purposes.展开更多
[Objective] In this study, the aim was to explore the annual dosage and allocation proportion of nitrogenous fertilizer for Zhoumai 22 in the condition of wheat-maize integration. [Method] The rules of growth and yiel...[Objective] In this study, the aim was to explore the annual dosage and allocation proportion of nitrogenous fertilizer for Zhoumai 22 in the condition of wheat-maize integration. [Method] The rules of growth and yield variation of Zhoumai 22 under different dosages of nitrogenous fertilizer and different distribution ratios were studied. [Result] With the increase of nitrogenous fertilizer application and distribution rate from maize to wheat, the physiological indexes of Zhoumai 22 population showed an increasing trend, while the yield presented the variation trend of increasing firstly and decreasing then. [Conclusion] Annual amount of nitrogenous fertilizer of 600 kg/hm2 and the distribution ratio of 5:5 in the condition of wheat- maize integration was beneficial to the high yield of the whole year's crops and Zhoumai 22.展开更多
Yellow Rust (stripe) rust (Puccinia striiformis West. f. sp. tritici) is one of the most epidemic diseases infect wheat in cold and wet regions. In 1988, this disease caused a loss of seasonal production amounted ...Yellow Rust (stripe) rust (Puccinia striiformis West. f. sp. tritici) is one of the most epidemic diseases infect wheat in cold and wet regions. In 1988, this disease caused a loss of seasonal production amounted 70% on wheat variety Mexipak in Syria, and recurrent infection in 2010, caused by a virulent race called Yr27, caused a considerable loss in the production of bread wheat cultivars (Cham 8, Cham 6 particularly) amounted 90%. Recently, 15 races of yellow rust had been addressed in Syria for seasons 2010-2014; 159E256, 166E254, 166E256, 255 E112, 0 E0, 64 E 6, 230 El50, 0 E 18, 198 El30, 166 El50, 102 El60, 128 E0, 126 El50, 214E150, and 6E16. The race 6E16 was the most frequent during the two seasons, while the race 255El12 was the most virulent, followed by the race 230E222 and the race 0E0 was the weakest one. This study revealed the presence of fourteen newly observed races in Syria. Molecular Variance Analysis of Molecular Variance (AMOVA) of 55 yellow rust Puccinia striiformis f.sp tritici isolates examined by Amplify Fragment Length Polymorphism (AFLP) revealed high genetic variation within population, and the dimensional scale analysis (MSD) and tree diagram showed that the Syrian yellow rust isolates were clustered in three groups: the first group contained isolates derived from durum wheat, the second one contained bread wheat isolates, but the third was made of isolates derived from both durum and bread wheat species.展开更多
A greenhouse experiment was conducted to test and compare the suitability of saline compost and saline irrigation water for nutrient status amendment of a slightly productive sandy clay loam soil, to study the macronu...A greenhouse experiment was conducted to test and compare the suitability of saline compost and saline irrigation water for nutrient status amendment of a slightly productive sandy clay loam soil, to study the macronutrient utilization and dry matter production of wheat (Triticum aestivum c.v. Gemmiza 7) grown in a modified soil environment and to determine the effects of compost and saline irrigation water on soil productivity. The sandy clay loam soil was treated with compost of five rates (0, 24, 36, 48, and 60 m3 ha-1, equivalent to 0, 3, 4.5, and 6 g kg-1 soil, respectively) and irrigation water of four salinity levels (0.50 (tap water), 4.9, 6.3, and 8.7 dS m-l). The results indicated that at harvest, the electrical conductivity (EC) of the soil was significantly (P 〈 0.05) changed by the compost application as compared to the control. In general, the soil salinity significantly increased with increasing application rates of compost. Soluble salts, K, C1, HCO3, Na, Ca, and Mg, were significantly increased by the compost treatment. Soil sodium adsorption ratio (SAR) was significantly affected by the salinity levels of the irrigation water, and showed a slight response to the compost application. The soil organic carbon content was also significantly (P 〈 0.05) affected by application of compost, with a maximum value of 31.03 g kg-1 recorded at the compost rate of 60 m3 ha-1 and the irrigation water salinity level of 8.7 dS m-1 and a minimum value of 12.05 g kg-1 observed in the control. The compost application produced remarkable increases in wheat shoot dry matter production. The maximum dry matter production (75.11 g pot-1) occurred with 60 ma ha-1 compost and normal irrigation water, with a minimum of 19.83 g pot-1 with no addition of compost and irrigation water at a salinity level of 8.70 dS m-1. Significant increases in wheat shoot contents of K, N, P, Na, and C1 were observed with addition of compost. The relatively high shoot N values may be attributed to increases in N availability in the tested soil caused by the compost application. Similarly, significant increases in the shoot contents of Na and C1 may be ascribed to the increase in soil soluble K and Cl. The increases in shoot P, N, and K contributed to the growth stimulation since P supplied by the compost was probably responsible in saline and alkaline soils where P solubility was very low.展开更多
基金Supported by Natural Science Foundation of China(Grant:30771156)Student Technology New Ideas Project of Liaocheng University(Grant:SRT08111SM2)~~
文摘[Objective] studying the influences of different UV-B radiation treatments in short time on some physiological characteristics of winter wheat seedlings was to provide reference for the mechanism of plant response to ultraviolet irradiation in short time. [Method] The winter wheat taken as materials were treated with 15 and 30 pW/cm^2 UV-B radiation, then the physiological indexes such as pigment content and photosynthetic rate were determined. [ Results] The UV-B treatment caused the declines of chlorophyll content, soluble protein content and water content of leaves, besides, dose-effect was existed. The decline of 30 pW/cm^2 treatment was bigger than that of 15 μW/cm^2 treatment. The influences of UV-B radiation on carotenoid content and anthocyanidin content were similar; the change trends were declined firstly then increased. The UVB treatment with two doses restrained the electron transport of PSⅡ, particularly; the inhibitory effect was biggest after treated 2 h, and then this effect was declined in 4, 6 and 8 h, so the dose-effect was existed. The UV-B radiation with two doses restricted photosynthetic rate and the inhibitory effect increased with the increase of treatment time. The high dose treatment caused huge damage to membrane system, while the result of low dose treatment was not obvious. [ Conclusion] UV-B radiation treatment had dose-effect on winter wheat seedlings in short time and the influence of high dose was bigger than that of low dose. With the increase of treatment time, the damage was alleviated; besides, the result was not similar to that of UV-B radiation in long time.
文摘New lines of wheat ( Triticum aestivum L.) was obtained by introducing the DNA of sorghum (Sorghum vulgare Pers.) into wheat cultivar 'Longchun 13'. The changes of respiratory pathway, contents of protein, Na+ and K+ in the leaves and roots of the new lines of wheat under salt stress were determined and compared with the control cultivar, 'Longchun 13'. The decrease of the content of K+ was observed with the increase of NaCl concentrations, but the decrease was more in the control than that in the new lines, and more in roots than in leaves. Content of proline and Na+ in both two wheats lines increased greatly, but the former increased more significantly in the new lines and the latter more significantly in control both in leaves and roots. The operation of the cyanide-resistant pathway of respiration was enhanced at different degrees after salt stress and it increased much more in roots and leaves of the control plant than that in the new lines, but the cytochrome pathway of electron transport was still the main one consistently. The possible significance of these changes was discussed.
基金the Start-up Research Grant of Excellent Talent in ZhongKai University of Agriculture and Engineering (G2360250)Shanxi Natural Science Foundation (20031067)~~
文摘[ Objective] The study aimed to reveal the effects of hypergravity on salt tolerance of wheat seedlings. [ Method ] The seed germination rate (Gr) and germination index (Gi) of wheat seedlings were measured under hypergravity of 600 × g or 1 000 × g for 4 h and under the stress of 0.4% or 0.9% salt solution. The catalase (CAT) activity and malondialdehyde (MDA) content of wheat seedlings were also measured under 0.4% salt stress. [Result] Compared with seedlings in CK group (no hypergravity or salt stress), the Gr and Gi of the seedlings in salt stress treatment decreased to different extents; while the Gr and Gi of the seedlings in treatment group (hypergravity and salt stress) increased compared with that in salt stress group. CAT in seedlings of hypergravity treatment was higher than that of CK group and 0.4% salt treatment group, meanwhile the MDA showed an opposite result. [ Conclusion] Hypergravity could enhance the salt resistance of wheat in specific range, and hypergravity of 600 × g for 4 h performed better than that of 1 000 ×g for 4 h.
基金Project supported by the National High-Technology Research and Development Program of China (863 Program) (No. 2003AA209030)the National Natural Science Foundation of China (No. 30030090)and the Hi-Tech Research and Development Program of Jiangsu Province (No. BG2004320).
文摘A knowledge model with temporal and spatial characteristics for the quantitative design of a cultural pattern in wheat production, using systems analysis and dynamic modeling techniques, was developed for wheat management, as a decision-making tool in digital farming. The fundamental relationships and algorithms of wheat growth indices and management criteria to cultivars, ecological environments, and production levels were derived from the existing literature and research data to establish a knowledge model system for quantitative wheat management using Visual C^++. The system designed a cultural management plan for general management guidelines and crop regulation indices for timecourse control criteria during the wheat-growing period. The cultural management plan module included submodels to determine target grain yield and quality, cultivar choice, sowing date, population density, sowing rate, fertilization strategy, and water management, whereas the crop regulation indices module included submodels for suitable development stages, dynamic growth indices, source-sink indices, and nutrient indices. Ewluation of the knowledge model by design studies on the basis of data sets of different eco-sites, cultiwrs, and soil types indicated a favorable performance of the model system in recommending growth indices and management criteria under diverse conditions. Practical application of the knowledge model system in comparative field experiments produced yield gains of 2.4% to 16.5%. Thus, the presented knowledge model system overcame some of the difficulties of the traditional wheat management patterns and expert systems, and laid a foundation for facilitating the digitization of wheat management.
文摘The aim of this work was to study the reactions of wheat (T. aestivum L.) and its wild congeners under salt stress. Physiological mechanisms that underlie traits for salt tolerance plantlets have been used to test some wheat species and to identify sources of salty tolerance. Stress conditions were founded by means of exposure of the plantlets in NaCI water solution, 1.68% that demonstrably differentiates the samples by growth parameters. Under laboratory conditions the ability of seedlings to bear a significant shortage of water, their ability to accumulate biomass, changing the parameters of linear growth processes and changes in water content in leaves and roots of seedlings under stress was determined. Interest is also the rate of growth of root fibrils in saline conditions. These experiments allowed to provide a comprehensive diagnosis of studied forms of wheat and make an initial opinion on their salt tolerance. Different features of abiotic stress responses of some wheat species at the early stages of development were shown that testifies necessi~ of great number of approaches at selection of genetic material for improvement of modern wheat eultivars. This work is the first phase of research for practical breeding.
基金Supported by Specialized Research Fund for the Doctoral Program of Higer Education(20120010110004)the Natural Science Foundation of Beijing(8142030)
文摘Wheat straw biodegradability during anaerobic digestion was improved by treatment with potassium hydroxide (KOH) to decrease digestion time and enhance biomethane production and fertility value. KOH concentrations of 1% (KI), 3% ([(2), 6% (K3) and 9% (l(4) were tested for wheat straw pretreatment at ambient temperature with a C:N ratio of 25:1.86% of total solids (TS), 89% of volatile solids (VS) and 22% of lignocellulose, cellulose and hemi- cellulose (LCH) (22%) were decomposed effectively with the wheat straw pretreated by 6% KOH. Enhanced bio- gas production and cumulative biomethane yield of 258 ml. (g VS)-1 were obtained increased by 45% and 41% respectively, compared with untreated wheat straw. Pretreated wheat straw digestion also yielded a digestate with higher fertilizer values potassium (l 38%), calcium (22%) and magnesium (16%). These results show that TS, VS and LCH can be effectively removed from wheat straw pretreated with KOH, improving biodegradability biomethane production and fertilizer value.
文摘Proline has been proposed to be an osmoprotector and scavenger of reactive oxygen species in plants subjected to water deficit. The aim of this work was to study the effects of drought on each wheat phenological stage (tillering, booting, heading, flowering and grain-filling) using stress parameters such as the relative water content (RWC), membrane stability index (MSI), lipid peroxidation through malondialdehyde levels (MDA) and determination of proline content (PRO). The Brazilian commercial elite cultivar Triticum aestivum cv. CD 200126 was submitted to eight days of water deficit stress at each stage. The perception of stress was low at tillering and high at the final stages of growth, as verified by the reduction in the MSI and RWC. However, an increase in the MDA was clearly observed. We observed a high proline accumulation when stress was applied, although it was not sufficient to prevent damages. These results indicate that the relevant stages to evaluate the effect of water shortage during wheat plant development are booting, heading and flowering.
基金Project (No. HEC/FD/2007/670) supported by the Higher EducationCommission (HEC), Pakistan
文摘Pakistani wheat varieties are grown over a wide agro-climatic range and as such are anticipated to exhibit yield and quality differences. It is therefore necessary to investigate the nutritional status of wheat varieties in terms of biochemical and physiochemical characteristics available for food and nutritional purposes in Pakistan. The result shows that wheat grains of different varieties contain a net protein level of 9.15%~10.27%, 2.15%~2.55% total fats, 1.72%~1.85% dietary fibers, 77.65×10-6~84.25×10-6 of potassium and 7.70×10-6~35.90×10-6 of sodium ions concentration, 0.24×10-6~0.84×10-6 of phosphorus, 1.44%~2.10% ash, 31.108~43.602 g of thousand grain mass (TGM) and 8.38%~9.67% moisture contents. This study is significant in providing an opportunity to explore the available wheat varieties and to further improve their nutritional excellence and also essential for setting nutritional regulations for domestic and export purposes.
基金Supported by the Project of National Wheat Industry Technology System in the"Twelfth Five-Year Plan"(CARS-3-2-34)~~
文摘[Objective] In this study, the aim was to explore the annual dosage and allocation proportion of nitrogenous fertilizer for Zhoumai 22 in the condition of wheat-maize integration. [Method] The rules of growth and yield variation of Zhoumai 22 under different dosages of nitrogenous fertilizer and different distribution ratios were studied. [Result] With the increase of nitrogenous fertilizer application and distribution rate from maize to wheat, the physiological indexes of Zhoumai 22 population showed an increasing trend, while the yield presented the variation trend of increasing firstly and decreasing then. [Conclusion] Annual amount of nitrogenous fertilizer of 600 kg/hm2 and the distribution ratio of 5:5 in the condition of wheat- maize integration was beneficial to the high yield of the whole year's crops and Zhoumai 22.
文摘Yellow Rust (stripe) rust (Puccinia striiformis West. f. sp. tritici) is one of the most epidemic diseases infect wheat in cold and wet regions. In 1988, this disease caused a loss of seasonal production amounted 70% on wheat variety Mexipak in Syria, and recurrent infection in 2010, caused by a virulent race called Yr27, caused a considerable loss in the production of bread wheat cultivars (Cham 8, Cham 6 particularly) amounted 90%. Recently, 15 races of yellow rust had been addressed in Syria for seasons 2010-2014; 159E256, 166E254, 166E256, 255 E112, 0 E0, 64 E 6, 230 El50, 0 E 18, 198 El30, 166 El50, 102 El60, 128 E0, 126 El50, 214E150, and 6E16. The race 6E16 was the most frequent during the two seasons, while the race 255El12 was the most virulent, followed by the race 230E222 and the race 0E0 was the weakest one. This study revealed the presence of fourteen newly observed races in Syria. Molecular Variance Analysis of Molecular Variance (AMOVA) of 55 yellow rust Puccinia striiformis f.sp tritici isolates examined by Amplify Fragment Length Polymorphism (AFLP) revealed high genetic variation within population, and the dimensional scale analysis (MSD) and tree diagram showed that the Syrian yellow rust isolates were clustered in three groups: the first group contained isolates derived from durum wheat, the second one contained bread wheat isolates, but the third was made of isolates derived from both durum and bread wheat species.
文摘A greenhouse experiment was conducted to test and compare the suitability of saline compost and saline irrigation water for nutrient status amendment of a slightly productive sandy clay loam soil, to study the macronutrient utilization and dry matter production of wheat (Triticum aestivum c.v. Gemmiza 7) grown in a modified soil environment and to determine the effects of compost and saline irrigation water on soil productivity. The sandy clay loam soil was treated with compost of five rates (0, 24, 36, 48, and 60 m3 ha-1, equivalent to 0, 3, 4.5, and 6 g kg-1 soil, respectively) and irrigation water of four salinity levels (0.50 (tap water), 4.9, 6.3, and 8.7 dS m-l). The results indicated that at harvest, the electrical conductivity (EC) of the soil was significantly (P 〈 0.05) changed by the compost application as compared to the control. In general, the soil salinity significantly increased with increasing application rates of compost. Soluble salts, K, C1, HCO3, Na, Ca, and Mg, were significantly increased by the compost treatment. Soil sodium adsorption ratio (SAR) was significantly affected by the salinity levels of the irrigation water, and showed a slight response to the compost application. The soil organic carbon content was also significantly (P 〈 0.05) affected by application of compost, with a maximum value of 31.03 g kg-1 recorded at the compost rate of 60 m3 ha-1 and the irrigation water salinity level of 8.7 dS m-1 and a minimum value of 12.05 g kg-1 observed in the control. The compost application produced remarkable increases in wheat shoot dry matter production. The maximum dry matter production (75.11 g pot-1) occurred with 60 ma ha-1 compost and normal irrigation water, with a minimum of 19.83 g pot-1 with no addition of compost and irrigation water at a salinity level of 8.70 dS m-1. Significant increases in wheat shoot contents of K, N, P, Na, and C1 were observed with addition of compost. The relatively high shoot N values may be attributed to increases in N availability in the tested soil caused by the compost application. Similarly, significant increases in the shoot contents of Na and C1 may be ascribed to the increase in soil soluble K and Cl. The increases in shoot P, N, and K contributed to the growth stimulation since P supplied by the compost was probably responsible in saline and alkaline soils where P solubility was very low.