【摘要】 对褐飞虱各虫态和不同生育期水稻过冷却点的测定及在人工模拟低温条件下耐寒力的比较表明:褐飞虱各虫态的耐寒力明显高于水稻。证明在冬季低温降临后,水稻先行枯萎,褐飞虱在食料缺乏和低温的共同影响下相继死亡。 水稻生存的下限温度在0—-2℃间,可作为褐飞虱在我国越冬的温度指标。据此,对褐飞虱在我国大陆的越冬北界提出了讨论意见。更多还原

【Abstract】 The supercooling temperature of both the brown planthopper and the rice plant have been determined. The supercooling point of the insect is - 8.89±0.99, - 9.81±0.72. 9.70±0.86, - 7.66℃ for the macropterous female, the broachypterous female, the nymph in 5th instar and the egg. respectively. The supercooling point of long-shaped rice is -6.75±0.65, -5.64±0.48, -4.49±0.95, - 2.04±0.34℃ for the seedling, tellering, early spike formation and late spike formation stages respectively; the supercooling point of the round-shaped rice is - 5.12±0.43, - 5.80±0.79℃ for seedling and tellering stages respectively. The results show that the cold hardiness of brown planthopper is greater than that of rice plant. Because the brown planthopper can not survive without the living rice plants, the study of the cold hardiness of plants is more important than that of the brown planthopper. The different developmental stages of both the brown planthopper and rice plants were treated under various levels of low temperature. The results show that the critical low temperature for survival of various rice plants is about 0 to -2℃ in winter, and is higher than that of brown planthopper. Under conditions where rice is lacking the insect can survive only for 7 to 13 days in winter. The overwintering eggs of brown planthopper in the rice stem will fail to survive when the water content of the stem drops to 20%.Based on the results mentioned above, the northern boundary of overwintering of the brown planthopper in China has been discussed in the paper.更多还原