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为了探讨低温在灰飞虱Laodelphax striatellus(Fallén)种群发生发展中的作用,本文以南京冬季的旬平均最低温为依据,设定出-6～2℃的低温,研究了用该低温处理3～4龄若虫不同时间后,灰飞虱的存活、生长与繁殖特性。结果表明,灰飞虱3～4龄若虫有较强的耐低温能力,-6～2℃的温度下,其半致迷和半致死时间分别为1.22和20.49d。低温抑制了若虫的生长发育,发育历期明显延长。低温处理后成虫的性比有所提高,并且短翅率显著增加。3～4龄若虫低温处理1～7d后羽化的成虫有产卵前期缩短、寿命延长的趋势,但对繁殖力没有显著影响,并且低温处理2d后的产卵量要稍高于没有处理的对照。由此可见,-6～2℃低温的短期胁迫对灰飞虱种群的发生发展不会产生抑制作用。
In order to investigate the role of hypothermia in the occurrence and development of Laodelphax striatellus (Fallén) population in this study, a low temperature of -6 ~ 2 ℃ was set on the basis of the average daily minimum temperature in Nanjing in winter. The survival, growth and reproduction of Laodelphax striatellus in different instars after 4 instar nymphs. The results showed that the 3rd to 4th instar nymphs of Laodelphax striatellus had strong resistance to low temperature. The half-lethal and semi-lethal time of 3rd and 4th instar nymphs of Laodelphax striatellus were 1.22 and 20.49 days respectively at -6 ~ 2 ℃. Low temperature inhibited the growth and development of nymphs, the developmental duration was significantly prolonged. The adult sex ratio increased after low temperature treatment, and the short-winged rate increased significantly. After 3 ~ 4 instar nymphs were exposed to hypoxia for 1 ~ 7 days, the emergence of adult females had the tendency of shortening the spawning period and prolonging their life span, but had no significant effect on fecundity, and the fecundity after 2 days of low temperature treatment was slightly higher than that of the untreated control . Thus, short-term cold stress of -6 ~ 2 ℃ did not inhibit the occurrence and development of SBPH population.