论文部分内容阅读
调查了南京地区2007～2008年灰飞虱Laodelphax striatellus(Fallén)全年的种群结构和数量动态,结合当地温度资料分析了灰飞虱虫量与温度间的关系。结果表明,灰飞虱在南京地区存在明显的春秋季高峰期及冬夏季的低谷期,且夏季的低谷出现在夏季高温时期。越冬种群以高龄若虫为主,越夏种群的年龄结构在年度间变化较大,2007年以高龄若虫为主,而2008年则以低龄若虫为主。夏季采于田间的灰飞虱若虫能在室内稻苗上连续生长发育,并且饲养一个世代后其产卵量显著提高。由此说明,南京地区灰飞虱不是以滞育形式越夏。灰飞虱若虫的耐寒性很强,在不同温度下饲养及田间越冬的不同时期,其过冷却点均在-22℃以下,且无显著差异。
The population structure and population dynamics of Laodelphax striatellus (Fallén) in Nanjing during 2007-2008 were investigated. The relationship between the temperature and the population of Laodelphax striatellus (Fallén) was analyzed. The results showed that there was a significant spring and autumn peak and winter and summer trough in the Nanjing area, and the low trough in summer appeared in the summer high temperature period. The overwintering population is dominated by nymphs. The age structure of the population of summergrowth varied greatly during the year. In 2007, nymphs were dominated by nymphs, while nymphs dominated in 2008. During the summer, the brown planthopper nymphs in the field could grow and develop continuously in the indoor rice seedlings, and the spawning amount after feeding one generation was significantly increased. This shows that, Laodelphax striatellus is not diapause in the form of summer in Nanjing. The cold tolerance of Laodelphax striatellus nymphs was very strong. The supercooling points were all below -22 ℃ in different periods of feeding and field overwintering, with no significant difference.