Leveraging the achievements of the smart meteorological system nationwide,a meteorological monitoring and early warning system for alfalfa pests and diseases can be formed through the establishment of four systems,nam...Leveraging the achievements of the smart meteorological system nationwide,a meteorological monitoring and early warning system for alfalfa pests and diseases can be formed through the establishment of four systems,namely,"real-time monitoring system,forecasting and prediction system,monitoring and early warning system,and smart service system".It will enable intelligent,dynamic meteorological monitoring,early warning,and forecasting services for the occurrence and development of alfalfa pests and diseases,providing technical support for scientifically controlling their harm and improving yield and quality.展开更多
[Objective] The aim of this study was to investigate the effect of space flight factors on plant biomass in the generation of alfalfa carried by the satellite.[Method]Seeds from three lines of alfalfa were carried by ...[Objective] The aim of this study was to investigate the effect of space flight factors on plant biomass in the generation of alfalfa carried by the satellite.[Method]Seeds from three lines of alfalfa were carried by the seed-breeding satellite Shijian-8.After the satellite returned to the ground,stem diameter,primary branch number and current-year individual biomass of alfalfa were studied.[Result]After space flight,primary branch number and current-year individual biomass of alfalfa increased significantly,while the stem diameter had no significant change.Using the value over(the mean value of control + three standard deviation)as a criterion to screen,the variants with enlarged stem diameter,increased primary branch number and individual biomass was two,five and twelve respectively.[Conclusion]The obtained variants can be used in the variety improvement of alfalfa and its new variety breeding,but whether its favorable variation can inherit stably to the progenies needs further study.展开更多
[Objective]The aim was to solve the weeds existed in seedling period of alfalfa in Chongqing.[Method]The naked oat and common oat were selected.Through the analysis of determiners such as plant number,plant height,yie...[Objective]The aim was to solve the weeds existed in seedling period of alfalfa in Chongqing.[Method]The naked oat and common oat were selected.Through the analysis of determiners such as plant number,plant height,yield and weeds ratio,the oat type and sowing method were screened through all the accompany sowing crops to better control weeds in the seedling period of alfalfa.[Result]Compared with common oat,the tested naked oat as the companion crop of alfalfa seeding can prevent weeds more effectively;the proper companion-seeding disposal of alfalfa sowed in spring in Chongqing area was 15 kg/hm2 of alfalfa and 120 kg/hm2 of naked oat,sowing in strip in 40 cm row spacing;the proper mowing period of oat was during the time from May 11th to May 21st;the proper mowing period of alfalfa was ten days later.[Conclusion]Spring sowing oats with alfalfa can control seedling weeds effectively.展开更多
The agronomic and qualitative traits of 17 alfalfa varieties were analyzed in field and lab from 2006 to 2008, and these traits were evaluated by principal component analysis and cluster analysis. A total of 10 main t...The agronomic and qualitative traits of 17 alfalfa varieties were analyzed in field and lab from 2006 to 2008, and these traits were evaluated by principal component analysis and cluster analysis. A total of 10 main traits were classified as five factors： growth factor, quality factor, stem and leaf factors, plant factor and yield factor. These five factors and their correlation were selected for breeding. These 17 varieties can be divided into five clusters. The domestic varieties have better agronomic traits, while the introduced ones have better qualitative traits.展开更多
Nitrogen addition is rather important to the growth of alfalfa. In this study, the effects of different nitrogen application levels on various growth characteristics of alfalfa were investigated. The results showed th...Nitrogen addition is rather important to the growth of alfalfa. In this study, the effects of different nitrogen application levels on various growth characteristics of alfalfa were investigated. The results showed that nitrogen application exhibited no significant effects on plant height and stem diameter but posed significant effects on branch number of alfalfa. Branch number of alfalfa in each cutting raised with the increasing application level of nitrogen, with significant differences among different treatments （P〈0.05）; individual aboveground biomass increased with the increasing application level of nitrogen, but the increasing trend gradually tended to be steady from the first to the fourth cutting. Nitrogen application affected significantly （P〈0.05） individual aboveground biomass of alfalfa in the first, second and fourth cutting, but exhibited no significant effects on individual aboveground biomass of alfalfa in the third cutting. With the increase of nitrogen application level, total surface area, total volume, collar diameter and crossing number of alfalfa roots increased gradually, but total length, average diameter and furcating number of alfalfa roots increased first and then declined. Total length, average diameter and furcating number of alfalfa roots reached the maximum in N60 treatment.展开更多
[Objective] This study was to reveal the correlation between leaf area and drought resistance in different varieties of alfalfa.[Method] Using various alfalfa varieties as experimental materials,the drought resistance...[Objective] This study was to reveal the correlation between leaf area and drought resistance in different varieties of alfalfa.[Method] Using various alfalfa varieties as experimental materials,the drought resistance of leaves of drought-stressed alfalfa plants was assessed by measuring the content of free proline for analyzing its correlation with leaf area.[Result] Under drought condition,the drought resistance of alfalfa is directly related to leaf area in a positive correlation.[Conclusion] Leaf area could be used as an institutional assistant index to reflect the resistance of different alfalfa varieties.展开更多
[Objective] The aim of this study was to reveal and analyze the spatial distribution pattern of thrip（Odentot hrips lati） on alfalfa（Medicago sativa）.[Method] Within alfalfa plantation areas,experimental plots wit...[Objective] The aim of this study was to reveal and analyze the spatial distribution pattern of thrip（Odentot hrips lati） on alfalfa（Medicago sativa）.[Method] Within alfalfa plantation areas,experimental plots with the sizes of 10×10,10×20,10×30,20×30,20×40,20×80,30×30,30×40,30×50,40×40,40×50,40×80 and 50×50 m2 respectively were set up in the randomly selected sampling sites of 1 m ×2 m in size.During bud-emerging period and florescence period of alfalfa in the experimental plots,the number of thrips was counted and their distribution pattern was measured using XU Ru-mei＇s method.[Result] During bud-emerging period of alfalfa,the spatial distribution of thrips assumed an elliptic shape sized of 40×30-40×40 cm2 at horizontal level and that presented an ascending-falling trend of tress density down from the top at vertical level.During the florescence period of alfalfa,it showed a homogeneous distribution or randomly distributed pattern at horizontal level and a falling trend of tress density from the top to the apex to the root at vertical level.[Conclusion] Our results provide theoretical basis for field selection of insect-resistant alfalfa varieties.展开更多
文摘Leveraging the achievements of the smart meteorological system nationwide,a meteorological monitoring and early warning system for alfalfa pests and diseases can be formed through the establishment of four systems,namely,"real-time monitoring system,forecasting and prediction system,monitoring and early warning system,and smart service system".It will enable intelligent,dynamic meteorological monitoring,early warning,and forecasting services for the occurrence and development of alfalfa pests and diseases,providing technical support for scientifically controlling their harm and improving yield and quality.
基金Supported by the Special Fund of Basic Scientific Research-Related Subsidy of State-Level Scientific Research Institute for Public InterestKey Project of National Science and Technology Planning during"the Eleventh Five-year Plan"(2008BADB3B04)~~
文摘[Objective] The aim of this study was to investigate the effect of space flight factors on plant biomass in the generation of alfalfa carried by the satellite.[Method]Seeds from three lines of alfalfa were carried by the seed-breeding satellite Shijian-8.After the satellite returned to the ground,stem diameter,primary branch number and current-year individual biomass of alfalfa were studied.[Result]After space flight,primary branch number and current-year individual biomass of alfalfa increased significantly,while the stem diameter had no significant change.Using the value over(the mean value of control + three standard deviation)as a criterion to screen,the variants with enlarged stem diameter,increased primary branch number and individual biomass was two,five and twelve respectively.[Conclusion]The obtained variants can be used in the variety improvement of alfalfa and its new variety breeding,but whether its favorable variation can inherit stably to the progenies needs further study.
文摘[Objective]The aim was to solve the weeds existed in seedling period of alfalfa in Chongqing.[Method]The naked oat and common oat were selected.Through the analysis of determiners such as plant number,plant height,yield and weeds ratio,the oat type and sowing method were screened through all the accompany sowing crops to better control weeds in the seedling period of alfalfa.[Result]Compared with common oat,the tested naked oat as the companion crop of alfalfa seeding can prevent weeds more effectively;the proper companion-seeding disposal of alfalfa sowed in spring in Chongqing area was 15 kg/hm2 of alfalfa and 120 kg/hm2 of naked oat,sowing in strip in 40 cm row spacing;the proper mowing period of oat was during the time from May 11th to May 21st;the proper mowing period of alfalfa was ten days later.[Conclusion]Spring sowing oats with alfalfa can control seedling weeds effectively.
基金Supported by National Basic Research Program of China ( 973 Program) ( 2007CB108906)~~
文摘The agronomic and qualitative traits of 17 alfalfa varieties were analyzed in field and lab from 2006 to 2008, and these traits were evaluated by principal component analysis and cluster analysis. A total of 10 main traits were classified as five factors： growth factor, quality factor, stem and leaf factors, plant factor and yield factor. These five factors and their correlation were selected for breeding. These 17 varieties can be divided into five clusters. The domestic varieties have better agronomic traits, while the introduced ones have better qualitative traits.
基金Supported by National Natural Science Foundation of China(Grant No.31372370)~~
文摘Nitrogen addition is rather important to the growth of alfalfa. In this study, the effects of different nitrogen application levels on various growth characteristics of alfalfa were investigated. The results showed that nitrogen application exhibited no significant effects on plant height and stem diameter but posed significant effects on branch number of alfalfa. Branch number of alfalfa in each cutting raised with the increasing application level of nitrogen, with significant differences among different treatments （P〈0.05）; individual aboveground biomass increased with the increasing application level of nitrogen, but the increasing trend gradually tended to be steady from the first to the fourth cutting. Nitrogen application affected significantly （P〈0.05） individual aboveground biomass of alfalfa in the first, second and fourth cutting, but exhibited no significant effects on individual aboveground biomass of alfalfa in the third cutting. With the increase of nitrogen application level, total surface area, total volume, collar diameter and crossing number of alfalfa roots increased gradually, but total length, average diameter and furcating number of alfalfa roots increased first and then declined. Total length, average diameter and furcating number of alfalfa roots reached the maximum in N60 treatment.
基金Supported by National Nonprofit Institute Research Grant(BRF090202)~~
文摘[Objective] This study was to reveal the correlation between leaf area and drought resistance in different varieties of alfalfa.[Method] Using various alfalfa varieties as experimental materials,the drought resistance of leaves of drought-stressed alfalfa plants was assessed by measuring the content of free proline for analyzing its correlation with leaf area.[Result] Under drought condition,the drought resistance of alfalfa is directly related to leaf area in a positive correlation.[Conclusion] Leaf area could be used as an institutional assistant index to reflect the resistance of different alfalfa varieties.
基金Supported by Natural Science Foundation of Guizhou Province(J[2010]2248)~~
文摘[Objective] The aim of this study was to reveal and analyze the spatial distribution pattern of thrip（Odentot hrips lati） on alfalfa（Medicago sativa）.[Method] Within alfalfa plantation areas,experimental plots with the sizes of 10×10,10×20,10×30,20×30,20×40,20×80,30×30,30×40,30×50,40×40,40×50,40×80 and 50×50 m2 respectively were set up in the randomly selected sampling sites of 1 m ×2 m in size.During bud-emerging period and florescence period of alfalfa in the experimental plots,the number of thrips was counted and their distribution pattern was measured using XU Ru-mei＇s method.[Result] During bud-emerging period of alfalfa,the spatial distribution of thrips assumed an elliptic shape sized of 40×30-40×40 cm2 at horizontal level and that presented an ascending-falling trend of tress density down from the top at vertical level.During the florescence period of alfalfa,it showed a homogeneous distribution or randomly distributed pattern at horizontal level and a falling trend of tress density from the top to the apex to the root at vertical level.[Conclusion] Our results provide theoretical basis for field selection of insect-resistant alfalfa varieties.
