草地贪夜蛾卵寄生蜂——夜蛾黑卵蜂的种内识别及过寄生OA北大核心CSTPCD

Telenomus remus(Nixon)is an important egg parasitoid of Spodoptera frugiperda(J.E.Smith),a major invasive pest.In order to clarify the intraspecific host discrimination and the superparasitism of T.remus,the self-recognition(same individual)and conspecific-recognition(different individual)ability to recognize the hosts eggs parasitized at different time intervals were determined,and the superparasitism rate of single and multi-female T.remus under different host density were also investigated.The results showed no superparasitism in T.remus,either self-recognition or conspecific-recognition.After a single female T remus parasitizing for 24 h at different parasitoid-egg ratios,the percentage of 1st instar larvae of T remus in S.frugiperda eggs was less than 100％,and only one was found in each host egg.With multi-female T remus and sufficient hosts,and when parasitoid-egg ratios were1∶100,2∶200,4∶400,6∶600 and 8∶800,the percentage of unparasitized host eggs were 52.8％,67.2％,63.2％,53.6％and 51.2％,respectively,and the percentage of host eggs with one 1st instar larva were 47.2％,32.8％,36.8％,46.4％and 48.8％,respectively.With multi-female T.remus and insufficient hosts,and when parasitoid-egg ratios were 2∶20,3∶21,4∶20,7∶21 and 20∶20,the parasitism rates of T.remus were 60.0％,83.0％,95.0％,94.0％and 96.0％,respectively,and the superparasitism rates were 11.0％,38.0％,64.0％,73.0％and 92.0％,respectively,the average number of 1st instar larva of T.remus in a single host egg were 0.4,0.6,1.1,1.3 and 2.1,respectively,and the maximum number were 3.0,4.0,5.0,6.0 and 12.0,respectively.The results show that T.remus has the ability of self and conspecific-recognition,the superparasitism of a single female T.remus does not depend on host density.When the host is sufficient,the superparasitism of multi-female T.remus does not occur,but when the host is insufficient,the parasitism and superparasitism rate,the average and maximum number of 1st instar larvae in a single host egg increase with the increase of parasitoid-egg ratios.The parasitoid-egg ratio of 4∶20 is suitable for propagation of the wasp because it produces high parasitism rate,low superparasitism rate,and low internal competition.