关键词: 麦长管蚜, miR-263, 两性生命表, 生长发育, 种群预测

Abstract: 【Aim】 The English grain aphid, Sitobion avenae is a destructive pest in wheat production. This study aims to clarify the effects of miR-263 interference on the laboratory population of S. avenae, so as to provide a theoretical basis for the green prevention and control of wheat aphids. 【Methods】 The 1st instar nymphs of S. avenae were interfered with 400 nmol/L miR-263 agomir using nanomaterials as carriers, and the effects of miR-263 interference on the growth and development, reproduction, and population growth of S. avenae were evaluated using the two-sex life table. The water negative control (NCW) and nanomaterial negative control (NCS) were employed as the control groups. 【Results】 After miR-263 interference, the duration of both the 1st and 2nd instar nymphs of S. avenae was significantly longer than that of the NCW and NCS, that of the 3rd instar nymphs showed no significant difference from that of the NCW and NCS, and that of the 4th instar nymphs was significantly shorter than that of NCW. The entire nymphal duration was significantly extended after miR-263 interference. After miR-263 interference, the total developmental duration (25.42 d) was significantly longer than that of the NCS (23.73 d), but had no significant difference from that of the NCW (23.84 d). After miR-263 interference, the adult longevity and reproduction duration were slightly extended, and the number of offspring produced per female was increased, but showed no significant difference from those of the NCW and NCS. The pre-adult survival rate of S. avenae after miR-263 interference was significantly decreased to 43.33% as compared with those of the NCW and NCS (91.34% and 91.32%, respectively). The life table data showed that the intrinsic rate of increase (r), finite rate of increase (λ), and net reproductive rate (R₀) after miR-263 interference were significantly lower than those of the NCW and NCS. The mean generation time (T) after mir-263 interference was significantly prolonged as compared to that of the NCW and NCS. The population prediction results showed that the population size of S. avenae was approximately 80 000 at 60 d after miR-263 interference, significantly lower than the population sizes of 4.54 million of the NCS and 3.94 million of the NCW. 【Conclusion】 The miR-263 interference mainly affected the duration and survival rate of low instar nymphs, and had an inhibitory effect on the population growth of S. avenae. The results provide candidate genes for the development of RNAi-based biopesticides against S. avenae.

Key words: Sitobion avenae, miR-263, two-sex life table, growth and development, population prediction