Staygreen syndrome or Zhengqing in soybean has recently become a major issue for Chinese growers in the Huang-Huai-Hai river basin.Although previous studies revealed that staygreen can be induced when pods/seeds are d...Staygreen syndrome or Zhengqing in soybean has recently become a major issue for Chinese growers in the Huang-Huai-Hai river basin.Although previous studies revealed that staygreen can be induced when pods/seeds are damaged, it is unknown whether virus infection or insect infestation causes staygreen.To determine whether viral infection causes staygreen, a survey of soybean staygreen incidence in the Huang-Huai-Hai river basin was conducted in 2016 and 2017.Diseased samples were collected and analyzed using DAS-ELISA for Soybean mosaic virus, Watermelon mosaic virus, Bean pod mottle virus, Cucumber mosaic virus, and Bean common mosaic virus.The survey showed that the severity of soybean staygreen syndrome was most prevalent in Beijing, Henan, Shaanxi, and some parts of Shandong provinces, with yield losses from 0 to nearly 100%, but only a small fraction of samples were positive for the tested viruses.A field cage experiment and an insecticide treatment field trial were conducted to determine the contribution of the bean bug, Riptortus pedestris, to staygreen incidence.The field cage experiment showed that R.pedestris treatment resulted in shorter plants, more empty pods, increased numbers of abnormal seeds, and decreased yields.The field experiment showed that there were fewer R.pedestris and less soybean staygreen incidence in fields treated with insecticide than in untreated control fields.Together, these results suggest that R.pedestris infestation rather than virus infection induces staygreen syndrome and that growers in this region can mitigate staygreen syndrome via bean bug control.展开更多
The responses of three cultivars of Chinese cabbage (Brassica chmensis L.), one of the main vegetable crops in China, to different ratios of NH4+-N/NO3--N was investigated to find the optimal ratio of ammonium to nitr...The responses of three cultivars of Chinese cabbage (Brassica chmensis L.), one of the main vegetable crops in China, to different ratios of NH4+-N/NO3--N was investigated to find the optimal ratio of ammonium to nitrate for maximal growth and to explore ways of decreasing the nitrate content, increasing nitrogen use efficiency of Chinese cabbage, and determining distributions of nitrogen and carbon. Three cultivars of Chinese cabbage were hydroponically grown with three different NH4+-N/NO3--N ratios (0:10…展开更多
Seedlings of wheat (Triticum aestivum L.), Chinese cabbage (Brassica campestris L.) and mung bean (Phaseolus radiatus L.) were grown for 30 days in sterile sand media with 6 N treatments, i.e. NH4+-N, glycine-N, 3 dif...Seedlings of wheat (Triticum aestivum L.), Chinese cabbage (Brassica campestris L.) and mung bean (Phaseolus radiatus L.) were grown for 30 days in sterile sand media with 6 N treatments, i.e. NH4+-N, glycine-N, 3 different ratios of glycine-N:NH4+-N (NH4+-N was labeled with 15N) and a control receiving no N, to assess the importance of amino acids in excessive N nutrition along with inorganic N interactions. The contribution of nitrogen derived from glycine-N to total plant N was investigated. The total plant N of the three species treated with N was significantly greater (P < 0.05) than the control treatment. Also, seedlings from all the three species had significantly more total N as NH4+-N (P < 0.05) than at least two of the four treatments with glycine-N. However, for all species, differences in total N among treatments with a mixture of glycine-N and NH4+-N were mostly not significant. The contribution of N derived from glycine-N to plant total N content for all species increased with increasing glycine-N:NH4+-N ratio in the treatment solution. These results indicated that agricultural plants could effectively use organic nitrogen from organic nitrogen sources (e.g., glycine) and from organic and inorganic N mixtures (e.g., a glycine-N and NH4+-N mix). There were also genotypic differences in glycine-N and NH4+-N uptake by agricultural species.展开更多
高动态的计算环境使得QoS(qualicy of service)保障对于基于组件的分布式系统越来越重要,软件系统需要具备自我调整的能力以适应外部环境的变化.给出一种自适应的中间件配置框架,能够动态感知负载变化,并自动调整系统参数配置以保持用...高动态的计算环境使得QoS(qualicy of service)保障对于基于组件的分布式系统越来越重要,软件系统需要具备自我调整的能力以适应外部环境的变化.给出一种自适应的中间件配置框架,能够动态感知负载变化,并自动调整系统参数配置以保持用户所要求的服务质量.该框架的核心是一个基于分层排队网络的性能预测模型,用于指导搜索最优的资源配置,使性能需求得到最大的满足.在OnceAS应用服务器上进行原型实现,并以StockOnline应用做实验,比较了在使用和不使用该框架时的性能需求的满足情况.结果显示,在负载增加时,通过自配置框架的调控,应用性能需求的保障程度得到了较大的提升.展开更多
基金supported by the National Key Research and Development Program of China (2017YFD0101400) to T.HanChina Agriculture Research System (CARS-04) to T.Han and K.Li
文摘Staygreen syndrome or Zhengqing in soybean has recently become a major issue for Chinese growers in the Huang-Huai-Hai river basin.Although previous studies revealed that staygreen can be induced when pods/seeds are damaged, it is unknown whether virus infection or insect infestation causes staygreen.To determine whether viral infection causes staygreen, a survey of soybean staygreen incidence in the Huang-Huai-Hai river basin was conducted in 2016 and 2017.Diseased samples were collected and analyzed using DAS-ELISA for Soybean mosaic virus, Watermelon mosaic virus, Bean pod mottle virus, Cucumber mosaic virus, and Bean common mosaic virus.The survey showed that the severity of soybean staygreen syndrome was most prevalent in Beijing, Henan, Shaanxi, and some parts of Shandong provinces, with yield losses from 0 to nearly 100%, but only a small fraction of samples were positive for the tested viruses.A field cage experiment and an insecticide treatment field trial were conducted to determine the contribution of the bean bug, Riptortus pedestris, to staygreen incidence.The field cage experiment showed that R.pedestris treatment resulted in shorter plants, more empty pods, increased numbers of abnormal seeds, and decreased yields.The field experiment showed that there were fewer R.pedestris and less soybean staygreen incidence in fields treated with insecticide than in untreated control fields.Together, these results suggest that R.pedestris infestation rather than virus infection induces staygreen syndrome and that growers in this region can mitigate staygreen syndrome via bean bug control.
基金1 Project supported by the National Natural Science Foundation of China (No. 30270790).
文摘The responses of three cultivars of Chinese cabbage (Brassica chmensis L.), one of the main vegetable crops in China, to different ratios of NH4+-N/NO3--N was investigated to find the optimal ratio of ammonium to nitrate for maximal growth and to explore ways of decreasing the nitrate content, increasing nitrogen use efficiency of Chinese cabbage, and determining distributions of nitrogen and carbon. Three cultivars of Chinese cabbage were hydroponically grown with three different NH4+-N/NO3--N ratios (0:10…
基金1Project supported by the National Natural Science Foundation of China (No. 30370838) and the Specialized ResearchFund for the Doctoral Program of Higher Education (No. 20030335076).
文摘Seedlings of wheat (Triticum aestivum L.), Chinese cabbage (Brassica campestris L.) and mung bean (Phaseolus radiatus L.) were grown for 30 days in sterile sand media with 6 N treatments, i.e. NH4+-N, glycine-N, 3 different ratios of glycine-N:NH4+-N (NH4+-N was labeled with 15N) and a control receiving no N, to assess the importance of amino acids in excessive N nutrition along with inorganic N interactions. The contribution of nitrogen derived from glycine-N to total plant N was investigated. The total plant N of the three species treated with N was significantly greater (P < 0.05) than the control treatment. Also, seedlings from all the three species had significantly more total N as NH4+-N (P < 0.05) than at least two of the four treatments with glycine-N. However, for all species, differences in total N among treatments with a mixture of glycine-N and NH4+-N were mostly not significant. The contribution of N derived from glycine-N to plant total N content for all species increased with increasing glycine-N:NH4+-N ratio in the treatment solution. These results indicated that agricultural plants could effectively use organic nitrogen from organic nitrogen sources (e.g., glycine) and from organic and inorganic N mixtures (e.g., a glycine-N and NH4+-N mix). There were also genotypic differences in glycine-N and NH4+-N uptake by agricultural species.
基金Supported by the National Natural Science Foundation of China under Grant No.60573126(国家自然科学基金)the National Basic Research Program of China under Grant No.2002CB312005(国家重点基础研究发展计划(973))
文摘高动态的计算环境使得QoS(qualicy of service)保障对于基于组件的分布式系统越来越重要,软件系统需要具备自我调整的能力以适应外部环境的变化.给出一种自适应的中间件配置框架,能够动态感知负载变化,并自动调整系统参数配置以保持用户所要求的服务质量.该框架的核心是一个基于分层排队网络的性能预测模型,用于指导搜索最优的资源配置,使性能需求得到最大的满足.在OnceAS应用服务器上进行原型实现,并以StockOnline应用做实验,比较了在使用和不使用该框架时的性能需求的满足情况.结果显示,在负载增加时,通过自配置框架的调控,应用性能需求的保障程度得到了较大的提升.
