褐飞虱的迁人和翅型分化规律的研究

褐飞虱Nilaparvata lugens(Stal)属迁飞性水稻害虫，其成虫有短翅和长翅两种翅型。 褐飞虱迁入雌虫均未经过交配，其短翅型由一对显性等位基因控制。翅型分化同时受到遗传和内分泌系统的协调控制，外界条件如密度和寄主等因子通过内分泌系统来影响翅型的分化。褐飞虱翅型分化的敏感龄期雌虫为1～3龄，而雄虫为1-5龄；不同若虫蜜度处理对褐飞虱成虫的前翅形成有一定的影响。分蘖期水稻饲养的褐飞虱短翅型比例明显高于孕穗期水稻饲养的褐飞虱。不同密度下各生物型间的翅型分化差异不显著。迁入地的浙江各种群属温带型，其雌虫短翅率低且与密度呈显著负相关；菲律宾热带种群雌虫在不同密度下均为短翅型，而雄虫的短翅率随密度增加而上升。广西种群接近热带型，其雌虫短翅率高但不随密度而变化。试验各种群的雄虫在中等密度甚至高密度时其短翅率出现最高。

STUDIES ON THE IMMIGRATION AND THE WING-FORM DEVELOPMENT OF BROWN PLANTHOPPER, NILAPARVATA LUGENS (STAL)

Nilaparvata lugens (Stal), has two wing-forms, macropterous andbrachypterous. The brown planthopper (BPH) controlled by a pair of dominant genes,and coordinated by hormones excreted by endocrine which is affected by external factors, such as nymphal density and plant nutrients. The sensitive instars of BPH nymph for wing-form development are the Ist - 3rd instars in female and 1st - 5th instars in male respectively. The forewing length of BPH is affected by nymphal density. BPH feeding on rice plants at various stages have dfferent brachypterous ratios, tillering plants cause more brachypterous females than booting rice plants. There are no significant difference between the wing-form development and various BPH biotypes under various nymphal densities. The Zhejiang populations show low brachypterous ratios and have a negative correlation with nymphal density, belonging to the temperate type. The Philippine populations are almost brachypterous, however, the bracheypterous ratio of BPH males raise with the increase of nymphal density. The Guangxi population have a high brachypterous ratio,being similar to the tropical type. The results also indicate that the brachypterous ratios of males are the highest when the nymphal populations are at the medium (54-10 per tiller) or high (＞20 per tiller) densities.