论文部分内容阅读
褐稻虱(Nilaparvata lugens Stal)系本区水稻穗期常易暴发的害虫。每年夏初自南方随西南气流渐次迁入虫源。成虫寿命和产卵历期很长,有两个产卵高峰,峰距为5天左右,峰期可持续10天左右。产卵最适温度为23°—26℃,与温度的关系为y=4.58x-0.07x~2-0.0006x~2-49.58(sT=±2.48,F<0.05),最利产卵的水稻生育期为孕穗抽穗期。 渴稻虱为害水稻所造成的损失与每穴实际虫量成正相关,其迴归方程为y=0.39+0.31x(r=0.92),在同虫量相同虫龄的为害下,中梗受害最烈,单杂次之,单晚最轻。双季后作中籼稻最易受害,中梗次之,晚粳最轻。各生育期中以孕穗至乳熟初期为害的损失最大,乳熟中、后期次之,分蘖末期至孕穗期较轻。当每穴虫量特高时,水稻在短期内枯死倒伏。从测定看出:水稻穗期因褐稻虱致枯死的损失与齐穗后的天数成反相关,方程为y=109.908-1.8175x(r=-0.9540)。 通过研究,认为本区褐稻虱为害的允许损失阈限以控制在5％以下为宜,每穴的虫量标准主代为8—10头:前一代为0.3—0.5头:主代防治应在若虫第一高孵期,前一代则在成虫羽化前夕。
Nilaparvata lugens Stal is a pest that is prone to outbreak in the heading stage of rice in this area. Beginning of summer each year with the Southwest airstream gradually moved into the source of insects. Adult life and oviposition duration is very long, there are two spawning peaks, the peak distance of about 5 days, the peak sustainable 10 days. The optimum temperature for spawning was 23 ° -26 ℃, and the relationship with temperature was y = 4.58x-0.07x ~ 2-0.0006x ~ 2-49.58 (sT = ± 2.48, F <0.05) Growth period booting heading. The loss caused by rice planthopper infestation was positively correlated with the actual insect quantity per hole, and the regression equation was y = 0.39 + 0.31x (r = 0.92). Under the damage of the same insect age, Strong, single second, the lightest night. After two seasons for indica rice is the most vulnerable, the secondary stem, late japonica lightest. In the whole growth period, the damage from booting to milk ripening was the largest, followed by milk ripening and later, and from the last tillering stage to the booting stage. When the amount of each worm is extremely high, the rice loses its weight in the short term. The results showed that the loss of withered rice caused by brown planthopper was inversely correlated with the number of days after heading, the equation was y = 109.908-1.8175x (r = -0.9540). Through the research, it is considered that the allowable loss threshold of brown planthopper damage in this area is controlled below 5%, and the standard number of the main insect in each hole is 8-10: the former generation is 0.3-0.5 head: the main prevention and control should be at Nymphs first hatching period, the former generation is on the eve of adult emergence.