浙江中部地区水稻黑条矮缩病的发生流行

报道了水稻黑条矮缩病再次回升流行的发生规律、分布格局、介体昆虫灰飞虱的种群动态及其相互关系、病害与产量的关系。感病秧苗、大田前期介体灰飞虱密度以及本田期再侵染是本田病害流行的３个重要部分，但早、晚稻有所不同；秧田期介体密度与移栽时、移栽后病害程度，本田初前期介体密度与抽穗期病害程度，株发病率与丛病率，病害程度与最终产量均有显著的关系。

EPIDEMICS OF RICE BLACK STRIP DWARF VIRUS IN CENTRAL PART OF ZHEJIANG PROVINCE

The regular pattern of repeaded infection of rice black strip dwarf virus distribution, population variation of the copula, Laodelphax striatella Fallen and their relation, relation between disease and yield are reported. Contagious seedlings, density of copula during earlier period and repeated infection during growth period were three inportant parts of prevalence, but early rice was different from late rice. The density of Copula during seedling, degree of disease before and after transplanting, density of copula during early growth, degree of disease during earing period, disease rate per plant, disease rate per cluster were positively or related with the yield.