The Research On Sperm Competition Ability Of Winged Dimorphic Males Of Velarifictorus Aspersus

The phenomenon of wing polymorphism is widely found in various insects.It is generally considered that there is a physiological balance between flight and reproduction of winged polymorphic insects.The results of the study on female support the above views,but the research reports of males are few.In this study,Velarificorus aspersus was used as the material to obtain microsatellite sequence by transcriptome technique,and the microsatellite loci were screened and analyzed.The time of spermatozoa attachment,oviposition and hatching rate were recorded by matching different wing males and long-wing or short-wing females.After the nymphs hatch,the DNA of parents was extracted as template,and 10 loci with the best amplification effect and high polymorphism were selected from 23 polymorphic microsatellite primers of V.aspersus for paternity identification,and the sperm quantity and survival rate of different winged males were detected.The main research results are as follows:1.A total of 30.79Gb was obtained from four transcriptome samples of V.aspersus,and 7878 microsatellite loci were found.64 microsatellite loci with three to six bases as repetition units were randomly selected for primer design,and 23 polymorphic loci were preliminarily screened by PCR amplification and capillary electrophoresis.2.A total of 78 alleles were obtained by genetic analysis of 23 polymorphic loci in 24 adults.Effective number of alleles(Ne)was 1.1350 to 3.1531,the observed heterozygosity(Ho)was 0.0455 to 0.8262,the expected heterozygosity(He)was 0.1189 to 0.8090,and the polymorphism information content(PIC)was 0.1151 to 0.7808,there are 8 loci significantly deviate from the Hardy-Weinberg equilibrium(P<0.01),and 2 loci significant deviation(P<0.05),the 13 loci were in accordance with Hardy-Weinberg equilibrium.At the same time,six other species of crickets were used to verify the universality of 39 primers for microsatellite of V.aspersus.The results showed that these primers were more applicable to Velarifictorus than those of non-Velarifictorus.Among them,the primers for Vasp-05,Vasp-24 and Vasp-60 were all effectively amplified in the tested crickets,providing reference value for the cross-species application of microsatellite of V.aspersus.3.The polymorphic information content(PIC)of the 10 polymorphic loci used for paternity identification of V.aspersus ranged from 0.232 to 0.704,and the average of polymorphic information content(PIC)was 0.4122.The exclusion rate of non-paternity increased with the increase of the number of microsatellite loci.When the 10 loci were used and the parents were unknown,the cumulative exclusion rate of non-paternity was the highest(CPE-PP=0.9876).There were no significant differences in the number of eggs(t test:t=1.655,P=0.1121)and hatching rate(t test:t=0.7338,P=0.4708)between short-wing and long-wing females.When mating with short-wing females,there was no significant difference in progeny ratio between long-wing males in the first mating order and short-winged males in the second mating order or between short-wing males in the first mating order and long-wing males in the second mating order.When mating with long-wing females,there was no significant difference in progeny ratio between long-wing males in the first mating order and short-wing males in the second mating order or between short-wing males in the first mating order and long-wing males in the second mating order.There was no significant difference in the attachment time of sperm membrane between short-wing and long-wing males during mating.There was no significant difference in the number and survival rate of sperm between short-wing and long-wing males of V.aspersus.These results prove that transcriptome technology can effectively develop a large number of microsatellite loci of V.aspersus and the screened 10 polymorphic microsatellite loci can be used for paternity identification of V.aspersus.It also showed that the sperm competition ability of short-wing males and long-wing males was equal,and their sperm competition pattern also showed that the last male sperm was preferred.