Occurrence and Chemical Control Techniques of Rice Black-streaked Dwarf Disease in Rongshui County

The chemical control technologies of southern rice black-streaked dwarf disease in hybrid rice were studied in Rongshui County,Guangxi,through a combination of investigation,observation and experiments.Three treatments were set up,namely,no water,shallow water and deep water,and each of which had a treatment area of 67 m^(2).Each treatment was sprayed once with 40 g of 200 million/g Bacillus subtilis wettable powder and 20-30 g of 25%pymetrozine wettable powder per 667 m^(2) in a mixture with 30 kg of water.On the day of spraying,100 diseased rice hills in each treatment were marked for field observation.The test results showed that the control of southern rice black-streaked dwarf disease should be done by draining the field water and spraying the mixture of B.subtilis and pymetrozine evenly,and a better effect can be achieved by keeping the field moist for 6-7 d after spraying.

Prevalence Characteristics of Rice Black-streaked Dwarf Virus Disease and Continuous Control Strategies

Through summarizing the prevalence characteristics of rice black-streaked dwarf virus disease(RBSDVD)in Linyi City of Shandong Province,this paper analyzed its prevalence is related to changes in farming and cultivation systems,the increase in the population of venomous Laodelphax striatellus Fallén and its own migration and spread,the poor disease resistance of cultivated varieties,and inadequate time of prevention and control.Besides,based on the practice of local control,it came up with some comprehensive control measures including strengthening monitoring,early warning and forecasting,planting resistant(tolerant)rice varieties according to local conditions,appropriately delaying the sowing(planting)period,supplemented by insect nets to cover seedlings,and making scientific use of chemical control.It is expected to provide a reference for the prevention and control of RBSDVD.

Detection,Occurrence,and Survey of Rice Stripe and BlackStreaked Dwarf Diseases in Zhejiang Province,China

The major viral diseases that occur on rice plants in Zhejiang Province, eastern China, are stripe and rice black-streaked dwarf diseases. Rice stripe disease is only caused by rice stripe tenuivirus （RSV）, while rice black-streaked dwarf disease can be caused by rice black-streaked dwarf fijivirus （RBSDV） and/or southem rice black-streaked dwarf fijivirus （SRBSDV）. Here we review the characterization of these viruses, methods for their detection, and extensive surveys showing their occurrence and spread in the province.

Resistance of Major Rice Cultivars in Hangzhou Area of China against Southern Rice Black-streaked Dwarf Virus

Resistance of 17 major rice cultivars in Hangzhou region of China against southern rice black-streaked dwarf virus was tested in the paper. The results showed that the incidence rate of southern rice black-streWed dwarf virus had certain positive correlation with quantity of white-backed planthopper （Sogatellafurci-fera） and resistance among various cultivars was significant. Two varieties, Yueyou 9113 and Tianyouhuazhan, were most susceptible ; Yongyou 8, Jiayou 2 and Xi-ushui 134 had best resistance and could be used as disease-resistant varieties to prevent the disease.

Disaster Prevention and Mitigation Technologies of Rice Virus Diseases Spread by Small Brown Planthopper (SBPH)

Rice stripe virus disease （RSVD） and rice black-streaked dwarf virus disease （RBSDVD） are two epidemic diseases in Yancheng City, Jiangsu Province in the last decade. The authors investigated the disaster regularity, prevention and control technology of RSVD and RBSDVD systematically. The occurrence and virus transmission of SBPH and disaster regularity of virus diseases were studied; the resistance of some rice varieties was cleared; the effects of physical and agricultural measures such as insect net blocking, appropriate late sowing and plowing on controlling occurrence and virus transmission of SBPH were figured out; a hatch of chemical agents were screened, providing efficient and harmless pesticides for effective control against SBPH and prevention against virus diseases. A set of disaster control and mitigation technologies was proposed in this paper, which was practical, sustainable, and easy to operate for the local planting patterns.

Epidemiological Characteristics of Maize Rough Dwarf Disease in Huang-Huai-Hai Plain

Maize rough dwarf disease is a common epidemic disease in large areas.Its epidemic and occurrence mechanism is a complex process.In this paper,the epidemiological characteristics and influencing factors of maize rough dwarf disease in Huang-Huai-Hai plain were elaborated based on the research results of maize rough dwarf disease at home and abroad for many years.The epidemic of maize rough dwarf disease is affected by many factors,such as the occurrence and virus carrying rate of the first generation small brown planthopper,accumulation of virus sources on gramineous crops and weed hosts,maize variety resistance,maize sowing date,maize growth period,crop layout,tillage system,climate and ecological environment.The key factors causing the outbreak and epidemic of maize rough dwarf disease are the planting of maize susceptible varieties,the meeting of maize seedling stage and the peak period of adult spread of the first generation of small brown planthopper.

水稻黑条矮缩病抗性遗传研究进展

水稻黑条矮缩病(RBSDVD,rice black-streaked dwarf virus disease)是以灰飞虱为主要传毒介体,由水稻黑条矮缩病毒(RBSDV,rice black-streaked dwarf virus)引起的一种水稻病毒性病害。介体灰飞虱一经染毒,终身带毒,但不能通过虫卵传毒。近十几年水稻黑条矮缩病在中国南方稻区广为流行,造成了水稻的严重减产。目前主要通过使用农药来防治其传毒介体灰飞虱,但由于灰飞虱种群数量大,导致其防治效果不佳,而且存在环境污染的忧患,故培育和利用抗水稻黑条矮缩病的水稻品种是综合防治水稻黑条矮缩病的基础。本文对水稻黑条矮缩病的分布及危害、抗病种质资源、抗性鉴定方法、抗病基因/QTL的定位、抗病分子机理及育种进行综述,为开展水稻黑条矮缩病抗性遗传研究和品种选育提供参考。