种子带毒率及有翅蚜降落量对SMV流行的影响

EFFECTS OF THE SEED-BORNE RATE AND LANDING AMOUNT OF ALATAE ON THE EPIDEMICS OF SOYBEAN MOSAIC VIRUS

大豆田主要迁飞降落的蚜虫有大豆蚜、棉蚜、玉米蚜、桃蚜、禾谷缢管蚜、豆蚜等,而大豆蚜的数量占绝对优势。当有翅蚜迁飞降落量大,同时田间病株率高时,SMV日侵染率高,最高达49.57%。田间有翅蚜发生和迁飞降落高峰一般在7月份,此时的迁飞降落蚜量和SMV的种子带毒率决定病害流行的程度。0.5%种子带毒率显著推迟SMV流行的时期。田间有翅蚜发生和飞翔高峰期推迟到8月份,0.2%和0.1%种子带毒率可控制SMV的流行为害。

The main species of alatae in soybean field in Harbin Region,Heilongjiang Province are Aphis glycines,A.gossypii,Rhopalosiphummaidis,Myzus persicae,R.padi,and A.craccivora,etc.,in which the A. glycines is predominant.There is close correlation between the alataenumber on soybean plants and the landing amount caught in green-pantrap.The infectivity of soybean mosaic virus(SMV),its highest re-cord is up to 49 57%,increased with the landing amount of alatae andfield incidence of soybean seedling(i.e.seed-borne ate).Generally,the peak period of alatae migration and alighting in soybean field is inJune;therefore,it is in this period that the extent of SMV occurrenceis determined by the situation of the two factors mentioned above.As the seed-borne rate of SMV decreased to 0.5%,the epidemic time ofthe disease is delayed significantly.It is indicated that if the peakflight peak period of alatae is postponed to August,and the seed-bornerate of SMV is lower than 0.2%,the prevalence of SMV can be pre-vented.