大豆田中蚜虫发生与大豆花叶病毒流行的研究

STUDIES ON THE RELATIONSHIP BETWEEN THE APHIDS AND EPIDEMIC OF SMV IN THE SOYBEAN FIELD

大豆田中有40余种蚜虫,其中出现频率在0.1％以上的有18种。传毒的大豆蚜和豆蚜7月中旬是发生高峰期;桃蚜是6月末、7月中旬和7月末3个发生高峰期。田间病株在7月下旬以后大量出现。田间早期病株是蚜传毒原。田间种传病株和早期蚜传病株对产量和种传率的影响较大。7月9日(R_2期)以后各期发病株的单株均产显著地高于以前各期发病株的产量。7月16日以前发病株的种传率明显地高于以后各期发病株的种传率,并且随发病时间的提早,种传率逐渐增高。6月末(R_1期)和7月初(R_2期)的病株种传率高达26％左右。

There are more than 40 species of aphids in the Soybean field. The frequency of 18 species were aboue 0.1 percent. The Soybean aphid and peanaphid are vectors of SMV which peaked in the middle of July. Spinach aphid, has three peak stages include the end of june, middle of July and end of July. Diseaced plants appearred largely after 20th july. Plants infected primarily by SMV were the virus source transmitted by aphid. Seedlings of seed-borne SMV and plants infected early by aphids carrying SMV decreased yield seriously and affected greatly percentage of seed-borne SMV.Yield of aplant which appearred diseased after 9th July(R_2 period) were much higher than before. Percentage of seed-borne SMV of plants which appearred diseased before 16 th July was hiyher clearly than Cater. The earlier disease developement, the more percentage of seed-borne SMV. It reached to the highest about 26 per cent at the end of June and early in July.