油菜病毒病流行规律研究

在10省(区)12县(市)按共同计划研究油菜病毒病流行规律结果:(1)品种的感染指数与病害成正相关,并与下述因素连应而对病害起作用。(2)油菜播种期与病害成负相关,回归斜率则因地区、年度等不同而变化。(3)油菜苗期蚜虫迁飞量与油菜角果发育期的发病量成极显著正相关。(4)秋季蔬菜(主要是萝卜、大白菜等)面积和发病率,与油菜发病成正相关。(5)夏季气温和降雨通过影响传毒蚜虫量和毒源发病量而影响油菜发病量。本研究在数量关系水平上,阐述了上述五项因素与病害的关系,建立了相应的数学模型。

EPIDEMIOLOGICAL STUDIES OF RAPESEED VIRUS DISEASE

The experiments were carried out in twelve counties (or cities ) of ten provinces for study of epidemical law of rapeseed virus disease.The results revealed that the following factors dominated the diseased epidemic: (a) The infectional index of variety was possitive correlation to disease incidence.It influenced disease incidence by it's interaction with following factors.(b) Relationship between sowing date and disease incidence showed negatire correlation.The interceptive variation changed by different arias and years. (c)Ths number of migratory aphids at seedling stage correlated significantly to PDP at silique development stage. (d) Both of area and PDP of virus source crops ( Cruciferous vegetable, for example, Raphanus sativus and Brassica bekinesis ) in the regions of winter rapeseed correlated to PDP of rapeseed in Winter. (e) Temperature and rainfall in Summer and Autumn influenced the number of migratory virus-borne aphids and disease incidence of virus soure crops, and further influenced PDp of rapeseed.The quantitative relationships between PDP and the above factors have been elucidated and their mathematics models were established in this paper.