Effect Of Temperature And Photoperiod On Development And Reproduction Of Athetis Lepigone (Moschler)

Athetis lepigon（eM schler）belong to Lepidoptera, Noctuidae, becoming a new kindof pest on the corn in our country in resent years. The damagement caused by A. lepigoneis serious gradually since broke out in Hebei provence in2005. In order to evaluate theeffects of the temperature and the photoperiod on the developmental and reproduction ofA. lepigone, the developmental duration, fecundity, development threshold temperatureand effective accumulated temperature, population parameter of A. lepigone werestudied and the life tables were constructed, at six different temperatures (16,20,24,28,32and36℃) and at20℃and24℃, combined with seven treatments of photoperiod(6L：18D,8L：16D,10L：14D,12L：12D,14L：10D,16L：8D,18L：6D), the results wereas follows:A. lepigone could not complete its life cycle at36℃. The developmental durationdecreased while the temperature was increased from16to32℃, and the shortestdevelopmental duration exited at32℃with27.2d. The development thresholdtemperature was8.69℃, and the effective accumulated temperature required for thewhole generation was604.45degree-days. The lifespan of the adults decreased with thetemperature increasing in the range of20~32℃, and there was no significant differencein terms of the lifespan between the male and female adults. The number of eggs laid perfemale were283.8and261.8at20℃and24℃, respectively, which was higher than thatat the other temperatures. Innate capacity of82.0and index of population trend of0.15were higher at24℃than that at the other temperatures, indicating that the optimumtemperature for the development and fecundity of A. lepigone was24℃.Photoperiod had significant influence on the growth and development of A. lepigone.Short photoperiod (light hours<10h) accelerated the development of the1st~4th larvalinstar. While the hours of light per day was ranged from6to14, some individuals of A.Lepigone at last larval instar, prepupa stage and pupa stage were developmental delay,most were at the prepupa stage. All individuals developed normally under the longphotoperiod (light hours≥16h).The hightest ratio of individuals of developing slowly was79.58%under thephotoperiod of6L:18D,8L:16D,10L:14D and12L:12D at24℃. The obtained ratio ofpupa, adult and emergency rate were the hightest under the photoperiod of16L:8D at24℃, were76.00%、73.00%、95.70%. Oviposition period and No. of eggs laid perfemalewere higher than that under the other photoperiods. More than90%of A. Lepigone were developmental delay under the photoperiod of6L:18D,8L:16D,10L:14D and12L:12Dat20℃. The obtained ratio of pupa, adult were the hightest under the photoperiod of16L:8D at60.33%and52.00%. The emergency were higher under the photoperiod of16L:8D and18L:6D at20℃, were86.43%、98.66%. The result showed that optimumphotoperiod for the development and fecundity of A. lepigone was16L:8D.Under the same photoperiod, with the the temperature increased, the developmentalduration decreased, the number of individuals developmental delay decreased, theobtained ratio of pupa, adult, emergency, oviposition and No. of eggs laid perfemaleincreased. Indicating that low temperature restrain the development and fecundity of A.lepigone.