Effects Of Physiology And Biochemistry ⁶⁰Co-? Ray On The Reproductive System Of Plutella Xyllostella?Linnaeus?

The Plutella xylostella belongs to Lepidoptera.It is mainly harmful to cruciferous plants and its fecundity is so strong,one female can lay 600 eggs.Due to the strong resistance to the pesticides,the serious overlap of generations makes it can propagate more than 17 generations a year in Guangdong.Using the method of chemical control to prevent the diamondback moth would cause pressure to the environment,pesticide residuces on vegetables,and a rapid increase in the resistance of the diamondback moth.The control effects of various chemical pesticides on the Plutella xylostella have been greatly reduced.With the development of Sterility Insect Technology?SIT?,insect irradiation sterility technology has been applied as an effective physical control method.Based on the research on the mechanism of irradiation sterility,this paper focuses on the effects of ⁶⁰Co-?ray irradiation on the male pupae reproductive system physiological and biochemical characteristics of the Plutella xylostella.The main results are as follows:By detecting the eclosion rate,egg laying amount and the hatchability of irradiated males,we found that:the hatchability of the egg produced by the female mated with 400Gy irradiated male was only 8.2%,and the eggs amount produced was reduced significantly.It indicated that the 400 Gy dose treated the Plutella xylostella made it completely sterile.The irradiation dose of 200 Gy caused male emergence rate,egg production and hatchability decreased which could produce F1 generation and the hatching rate was69.72%.Ultrastructural observation of the eggs showed,irradiation caused the F1generation segmentation sphere structure damage.The mating duration and spermatozoa transmission are also important factors affecting reproduction.Irradiated male mated with unirradiated female,the couple duration and sperm counts were no difference among 0 Gy,200 Gy and 400 Gy treatments.After irradiation of the 1,3,5 and 7 days,the results showed that there was no significant difference in the weight of the testes and the number of sperm bundles at each time point.After 200 Gy and 400 Gy irradiation,the number of eupyrene sperm bundles,apyrene sperm bundles and the total number of sperm bundles were not significantly affected by the irradiation.There was no significant difference between the ratio of eupyrene/apyrene sperm bundles on the 1st and 3rd day,only on the 5th day was significantly lower than the control,and was significantly higher on the 7th day.Effects of irradiation on reproductive system of the Plutella xylostella male suggested?indicated?that irradiation resulted in deformity head of the eupyrene sperm bundles,such as double head,head depression,shrinkage and other deformities.The deformity rate of sperm bundles in adult testis after irradiation was significantly higher than that in pupae testis.Ultrastructural observation of adult testis revealed that 400 Gy resulted in deformity of mitochondrial derivatives in sperm flagellum structure,including increasing in the number of mitochondrial derivatives,or sperm adhesion.Irradiation induced damage of sperm tissue of the Plutella xylostella.After irradiation,the activities of LDH and ACP in spermary increased,reached the peak at 24 h after emergence,and then decreased.The results of TUNEL showed that irradiation could induce apoptosis.The results of PCR showed that the degree of apoptosis of irradiated adults was higher than that of pupae.The results of Western Blot were consistent with PCR.The apoptosis was more obvious in the group treated with 400 Gy.