锈赤扁谷盗非成熟发育阶段在3种谷物中的发育历期及预测模型研究

Developmental durations and prediction model of immature stage of the rusty grain beetle Cryptolestes ferrugineus(Stephens)in three kinds of grains

温度和食物是影响昆虫生长发育的两个重要因素。本文测定了24、28℃和32℃条件下锈赤扁谷盗Cryptolestes ferrugineus(Stephens)非成熟发育阶段(卵、幼虫和蛹)在全麦粉、玉米粉和糙米粉中的存活率和发育历期。研究结果显示,试验温度范围下,温度升高,锈赤扁谷盗幼虫和整个非成熟发育阶段的存活率显著升高,卵、幼虫、蛹及整个非成熟发育阶段的历期显著缩短。在32℃时全麦粉中非成熟阶段总发育历期最短、存活率最高,为34.2 d和60.9%。用最小二乘法计算各阶段发育起点温度和有效积温,结果显示,3种谷物对锈赤扁谷盗卵、幼虫、蛹及整个非成熟阶段的发育起点温度没有显著影响,但对幼虫阶段有效积温有显著影响;在全麦粉、玉米粉和糙米粉中锈赤扁谷盗整个非成熟发育阶段的发育起点温度分别为(17.4±0.3)(16.9±1.6)℃和(16.4±0.7)℃;有效积温分别为(773.4±0.1)(888.0±125.2)日·度和(1 009.3±61.9)日·度。最后,根据不同温度下锈赤扁谷盗各发育阶段在3种谷物中的发育速率分别建立了发育速率预测模型。研究结果为锈赤扁谷盗在不同储粮环境中发生的短期精准预报提供了科学依据。

Temperature and diet are two important factors affecting the development of stored-product pests.The survival rates and developmental durations of immature stage(egg,larva,and pupa)of Cryptolestes ferrugineus(Stephens)fed on whole wheat flour,corn flour and brown rice flour were examined at 24,28℃and 32℃.The results showed that the survival rate of larva and total immature stage significantly increased,and the developmental duration of egg,larva,pupa,and total immature stage of C.ferrugineus significantly shortened in the experimental temperature range.At 32℃,the total developmental duration of the immature stage in the whole wheat flour was the shortest(34.2 d),and the survival rate was the highest(60.9%).Then,the developmental threshold temperature and effective accumulative temperature for each developmental stages were calculated by least squares method.There were no significant differences in the developmental threshold temperature of egg,larva,pupa and the total immature stage in different cereals,but the effective accumulated temperature of the larval stage was significantly varied;the developmental threshold temperature and degree-day accumulation were different in different grains for total immature stage:(17.4±0.3)℃and(773.4±0.1)degree-days in whole wheat flour;(16.9±1.6)℃and(888.0±125.2)degree-days in corn flour;and(16.4±0.7)℃and(1009.3±61.9)degree-days in brown rice flour,respectively.Finally,the development rate prediction models were established according to the development rate of each stage in three kinds of grains at different temperatures.The results provide a scientific basis for the short-term accurate prediction of the occurrence of the rusty grain beetle in different grain storage bins.