Effects Of Temperature And Photoperiod On The Reproductive Biology Characteristics Of Euzophera Pyriella Yang

Euzophera pyriella Yang is the main stem borer on fruit trees in Xinjiang,it has a wide range of hosts and does harm to a variety of fruit trees,the larvae of the E.pyriella mainly bore in the branches of fruit trees,and the adults are the key period for the control work.In the process of indoor population feeding,it is found that temperature and photoperiod can regulate the eclosion,mating and oviposition of adults.At present,the regulation mechanism of temperature and photoperiod on the adult behavior of E.pyriella is not clear.Therefore,this experiment focuses on the effects of temperature and photoperiod on the eclosion,mating and reproduction of E.pyriella adults,compares the differences of adult eclosion,mating and reproductive ability under the conditions of five temperatures and five photoperiods,and clarifies the internal relationship between adult behavioral rhythm and temperature and photoperiod,build sexual life table age-stage,to provide reference conditions for indoor breeding of E.pyriella and make prediction and control more accurate and effective,mainly have the following conclusions:1.Effects of temperatures on reproductive biology characteristics of E.pyriella（1）25℃was suitable for adult eclosion.High temperature and low temperature will inhibit eclosion.High temperature makes eclosion activities earlier and more concentrated.Eclosion can occur all day,mainly in the daytime.Eclosion peak time of female and male adults was slightly different,but they concentrated in 11:00-14:00.（2）The mating duration of adults increased first and then decreased with increasing temperature,the longest was 2.13 h at 21℃.Adults can mate on the first day after eclosion,mating activity concentrated in18:00-03:00,there was no mating activity from 03:00 a.m.to 18:00 p.m.the next day,mating peak concentrated in 21:00-23:00.（3）The longevity of adults decreased with increasing temperature,the longevity of female was always greater than male.Preoviposition period of adults shortened with increasing temperature,the longest at 21℃,which was 4.17 d.The egg number per female and hatching rate reached the maximum at25℃,which were 47.82 grain and 89.22%.Oviposition activities of adults mainly concentrated in night,oviposition peak concentrated in 22:00-02:00.（4）The population trend index and net reproductive rate of E.pyriella increased first and then decreased with increasing temperature,reached highest at 25℃,19.33%and 19.66 respectively.The finite rate of increase and intrinsic rate of increase reached maximum at 29℃,which were 1.0638 d^-1 and 0.0618d^-1 respectively.At 25℃,population trend index,net reproductive rate,intrinsic rate of increase and finite rate of increase of E.pyriella were higher,mean generation time was also shorter,indicating that 25℃was suitable for development and reproduction of E.pyriella.2.Effects of photoperiods on reproductive biology characteristics of E.pyriella（1）The eclosion rate was the highest when photoperiod was 12L:12D.Medium light time was suitable for adult eclosion,and too long or too short photoperiod will inhibit eclosion.Increasing photoperiod can advance eclosion activity of adults,while shortening photoperiod is the opposite.Under different photoperiods,the eclosion peak of adults was advanced with increasing photoperiod.（2）The mating rate of adults was the highest when photoperiod was 14L:10D,which was 85.00%.The mating duration increased with increasing photoperiod,the longest was 1.83 h when photoperiod was16L:8D.The number of mating was the most when photoperiod was 16L:8D,which was 1.28 time.The mating activity under different photoperiods began about 2 h before the end of photoperiod,there was no eclosion activity in other photoperiods,mating peak was delayed with increasing photoperiod.（3）The longevity of adults increase with increasing photoperiod.Except 16L:8D,longevity of female was always greater than male.The preoviposition period increased first and then decreased with increasing photoperiod,and it was the longest when photoperiod was 10L:14D,which was 3.61 d.When photoperiod was 12L:12D,the egg number per female was the most,while was 51.02 grain.Hatching rate was the highest when photoperiod was 16L:8D,which was 91.13%.Oviposition activity of adults under different photoperiods mainly occurs at night,peak time of oviposition was delayed with increasing photoperiod.（4）The intrinsic rate of increase and finite rate of increase of E.pyriella reached the maximum when photoperiod was 16L:8D,which were 0.0712 d^-1 and 1.0712 d^-1 respectively.The net reproductive rate showed the highest trend with increasing photoperiod,and reached the highest at 14L:10D,which was19.66.The mean generation time and population trend index increased first and then decreased with increasing photoperiod,and reached the maximum at 12L:12D,which were 56.09 d and 19.56 respectively.When photoperiod was 14L:10D,population trend index,net reproductive rate,intrinsic rate of increase and finite rate of increase of E.pyriella population were higher,indicating that 14L:10D was the most suitable photoperiod for the survival and reproduction of E.pyriella.