温度对桃蛀螟生长发育和繁殖的影响

 为了明确温度对桃蛀螟Conogethes punctiferalis (Guenée)生长发育和繁殖的影响， 本实验在恒温条件（15， 19， 23， 27和31℃共5个温度梯度）下， 以板栗为寄主食料， 研究了温度对桃蛀螟实验种群生长发育和繁殖的影响。结果表明： 温度对桃蛀螟各虫态的发育历期、 存活率、 蛹重以及种群繁殖力有显著影响。在15~27℃范围内， 各虫态的发育历期均随温度的升高而缩短， 发育速率与温度呈显著正相关。但是， 当温度上升至31℃时， 幼虫生长发育受到抑制， 其发育历期比27℃时延长了1.11 d， 而卵期、 蛹期和产卵前期仍符合随温度升高趋于缩短的趋势。此外， 15℃下桃蛀螟5龄幼虫发育停滞， 表明老熟幼虫的发育起点温度高于其他低龄幼虫。桃蛀螟世代存活率随环境温度变化的大小顺序为23℃>27℃>19℃>31℃， 其中， 23~27℃的存活率较高， 为54.44%~63.56%， 31℃时为4.30%， 说明温度过高或过低均不利于其生长发育。成虫产卵量在23℃时最高， 单雌平均产卵量达55.00粒， 其次为19℃和27℃， 单雌平均产卵量分别为43.30和39.70粒； 31℃下产卵量最少， 仅为20.90粒。由直接最优法计算得到桃蛀螟卵期、 幼虫期、 蛹期、 产卵前期及全世代的发育起点温度分别为10.37， 10.06， 14.27， 7.47和11.85℃， 有效积温依次为70.84， 287.71， 118.42， 58.33和509.06日度。研究结果为桃蛀螟发生期的预测预报提供了基础参考数据， 对指导生产实践有实际的应用意义。

Effects of temperature on the development and reproduction of the yellow peach moth, Conogethes punctiferalis (Lepidoptera: Pyralidae)

To illustrate the influences of temperature on development and reproduction of the yellow peach moth, Conogethes punctiferalis (Guenée), the development and fecundity of C. punctiferalis were investigated at five temperatures (15, 19, 23, 27 and 31℃), with chestnut served as food. The results showed that temperature had significant effects on the developmental duration, survival rate, pupal weight and reproduction of C. punctiferalis. The developmental duration of every stage of C. punctiferalis reduced with increasing temperatures from 15 to 27℃, and there was a positive relationship between developmental rate and temperature. Further increase of temperature to 31℃, however, is unfavorable to its larval development. The larval developmental duration at 31℃ was 1.11 d longer than that at 27℃, while the developmental durations of egg, pupa and preoviposition stages kept shorter at high temperature (31℃) than those at low temperatures. In addition, the development of the 5th instar larva ceased at 15℃, indicating that a higher threshold temperature was needed for the development of mature larva than lower instar larva. The generation survival rate of the yellow peach moth at different temperatures decreased in the order of 23℃>27℃>19℃>31℃, of which the survival rate was high (54.44%-63.56%) at 23-27℃ and low (4.30%) at 31℃, suggesting that excessively high or low temperature was unfavorable to its survival. The oviposition amount of C. punctiferalis was the largest (averagely 55.00 eggs laid by per female) at 23℃, followed by those at 19℃ and 27℃ (43.30 and 39.70 eggs laid by per female, respectively), and the least was 20.90 eggs per female at 31℃. Based on the direct optimal method, the developmental threshold temperatures for egg stage, larval stage, pupal stage, preoviposition stage and the whole generation were 10.37, 10.06, 14.27, 7.47 and 11.85℃, respectively, and the corresponding effective accumulated temperatures were 70.84, 287.71, 118.42, 58.33 and 509.06 degree-days, respectively. The results provide the basis for forecasting the occurrence of the yellow peach moth and are applicable in agricultural practices.