Biochemical Mechanisms Of Different Cold Tolerance Between Male And Female Stenocatantops Splendens

Stenocatantops splendensis is widely distributed in southern China and Southeast Asia and overwinters with adults.There are differences in the cold resistance of overwintering male and female adults.The supercooling point of overwintering female adults is significantly lower than that of male adults.In this study,the male and female adults of Stenocatantops splendensis were collected from the suburbs of Changsha,through the detection of total sugar,trehalose,glycogen,glycerin,protein and fat content in the body during the early wintering,during wintering and later wintering periods,compare the dynamic changes of cold-tolerant substances between male and female adult of Stenocatantops splendensis;After cold acclimation,detect the content of cold-resistant substances and determine the supercooling point,comparing the effects of cold acclimation on the accumulation of cold-tolerant substances and changes in supercooling points of male and female adults,to clarify the biochemical mechanism of the difference in cold tolerance between overwintering male and female adults of Stenocatantops splendensis.The main findings are listed as follows:(1)There were no significant difference in the total sugar content of male and female adults in the early wintering,during wintering and later wintering periods,both male and female,significantly decreased in the later wintering periods.During wintering,the trehalose content of both male and female adults showed an upward trend.The accumulation of trehalose in female adults is significantly higher than that in male adults in the early wintering,during wintering and later wintering periods,while the glycogen content showed the opposite decreasing trend.As a basic substance for energy storage and metabolism,whether it is a female adult or a male adult,the fat content is greatly reduced during the winter.The protein and glycerin changes of male and female adults during wintering are not obvious.(2)The male and female adults were cold acclimated at different temperatures and at different times,and the results showed:After cold acclimation,the total sugar content of male and female adults increased to varying degrees,especially the cold acclimation treatment group of 4? and 8?,with the extension of cold acclimation time,its total sugar accumulation continues to increase.Cold acclimation at 4? and 8? significantly promoted the rapid accumulation of trehalose in male and female adults,but the promotion effect of female adults was more significant.Correspondingly,after cold acclimation,glycogen content showed the opposite trend compared to the trehalose content.After cold acclimation,the content of protein and glycerin tended to decrease,but the fat content did not change significantly.(3)Cold acclimation has the effect of reducing the supercooling point of male and female adults.Among them,the cold acclimation at 4? for 15 days,the supercooling point of female adults decreased from-5.76±0.82 ? in the control group to-8.05±0.81?,male adults reduced from-5.02 ± 0.87? in the control group to-7.49 ± 0.57 ?.The above results indicate that the accumulation of the cold-tolerant substance of Stenocatantops splendensis is trehalose accumulation type,trehalose is the main small molecule cold-tolerant substance accumulated during adult wintering.and there is a certain mutual conversion relationship between trehalose and glycogen in their body,female adults have higher cold tolerance than male adults and are related to trehalose accumulation.Cold acclimation can promote the accumulation of cold-resistant substances,reduce the supercooling point,and enhance cold resistance.