Mating Behavior And Internal Reproductive System Of The Ostrinia Furnacalis

To reduce the resistance of pesticide and environmental risk,the application of synthetic sex pheromone plays the important role in the control of pest and monitoring and pre-alarming system.The Asian corn borer,Ostrinia furnacalis(Guenée),is the primary pest on corn.Its serious harm has become the main factor affecting the high yield and quality of corn and national food security,which is a major problem in production.However,due to the unclear mating mechanism of Asian corn borers,there are some problems in the efficacy of the synthetic sex pheromone for trapping.This study investigated the mating preference and reproductive fitness of male moth as influenced by mating experience and age,and established the method of judging the mating status of male moths by observing and compareed the characteristics of male reproductive system of male moths with different mating status and age.On this basis,we investigate mating status of male moth trapped by sex pheromone.The results will provide the reference for the control of Asian corn borers by using synthetic sex pheromone.The main results showed:1.In the two-way spouse selection test,the mating success rate was significantly affected by mating age and mating experience(?2 = 4.442,df = 1,P = 0.035).When faced with newly emerged and male moths that emerged for 48 h,61.90% of female moths chose to mate with newly emerged male moths;when faced with males after 48 h and 48 h after emergence,57.69% females Mating with unmated male moths;when confronted with male moths newly mated and 48 h after mating,13.64% of females choose males that have just been mated,significantly less than 50%(?2 = 11.636,df = 1,P <0.001).Female moths that mate with male moths 48 hours after mating have the longest lifespan,and female moths that mate with newly emerged unmated male moths have the shortest lifespan;male moths and newly emerged male moths that have experienced mating have significantly prolonged female moth spawn Period(P < 0.05).2.The internal reproductive system of the O.furnacalis male moth includes testis,vas deferens,seminal vesicles,ductus ejaculatorius duplexes,accessory glands,primary simplex.According to the constriction,the primary simplex can be divided into 5 segments(PS1-PS5)The PS1 segment and the PS5 segment significantly changed after mating,and the intensity was used to represent the liquid transparency in the single ejaculatory duct.According to the liquid intensity PS1 segment and PS5 segment can be divided into PS1 a,PS1p,PS5 a,PS5p four parts.The PS1 segment of the primary simplex of the unmated male moth is transparent,and there is white liquid in the PS5 segment.The age has no obvious effect on the intensity of the liquid in the primary simplex.The intensity of PS1 and PS5 changed significantly after mating.As the time after mating increases,the intensity of the liquid gradually recovers,but the recovery speed of each part is different.The liquid in the primary simplex returns to the unmated state after 68 hours after mating.However,the PS5 segment occasionally retains a gap.If the gap disappears,the length of the PS5 p is greater than 1 mm,which is different from the unmated male moth.3.Male O.furnacalis moth sperm size is independent of body size.The testis size affected by age and mating status(P< 0.05).The diameter and volume of the testis of male moths with mating experience decreased significantly with increasing age(P< 0.001),which was significantly greater than that of unmated male moths.4.By investigating the mating status of sex pheromone trapped Asian corn borer male moths in field.It was found that 50.59% of the male moths showed characteristics of unmated reproductive system,and 49.41% of the male moths showed characteristics of unmated reproductive system.Male moths at 3 days accounted for 34.84% of the total amount of moths,males over 3 days after mating accounted for 13.78%,and males no more than 1 d after mating accounted for 0.78%.The control effect of pheromone clusters on trapping and killing Asian corn borer male moths needs to be improved.The sex pheromone attracts the testis of Asian corn borer male moths with a larger volume,which is significantly larger than the testis of 1-3 day old male moths,which is similar to the volume of the test chambers of 0day old male moths.The sex pheromone trapped male moths have a relatively young age and strong mating ability,which can reduce the proportion of male moths that mate multiple times in the field.