CMV 通过影响效应因子 MpC002 的表达干预桃蚜种群 增长的机制.

【Objective】 Peach aphid (Myzus persicae) is an important vector of cucumber mosaic virus (CMV), and the effector MpC002 plays a key role in the feeding process. CMV and MpC002 are both present in aphid saliva, but little is known about their interaction and how MpC002 facilitate virus transmission. Therefore, this study aims to preliminarily investigate the mechanism by which CMV influences the expression of MpC002 for interfering the population growth of GPA. .【Method】 The CMV copy number was calculated by the standard curve y=-3.163 1x+39.763, via applying the absolute quantitative polymerase chain reaction (qPCR) 【Result】 The CMV content in the peach aphid fed with CMV-infected pepper reached the highest at 10 s, then the CMV content decreased gradually along with the feeding time, and its virulence acquisition process conformed to the characteristics of non-persistent transmission. In addition, the expressions of MpC002 in the peach aphids fed on CMV-infested peppers within 5 min-24 h significantly decreased to 37%-58%, compared with those before feeding. While feeding on CMV-infested peppers, the average developmental duration of third, fourth instar and the entire nymph stages were 1.58, 2.07 and 6.47 d, which were significantly longer than those fed on the untreated peppers (1.25 d, 1.47 d and 5.33 d) ; in contrast, the developmental duration of the first and second instars did not show significantly difference between CMV-infested and untreated peppers. The average laying period, the total peach aphid number and the average peach aphid in a single day were 10.03 d, 16.87 and 1.67, which were significantly shorter than those of untreated peppers (14.27 d, 39.73 and 2.82) . In addition, analysis of GPA life table parameters revealed that the net growth rate, intrinsic rate of increase, and finite rate of increase were 16.87, 0.21, and 1.21, respectively, which were significantly lower than those of peach aphids feeding on untreated peppers (39.73, 0.31, and 1.36, respectively), whereas the mean generation time (13.02 d) and the population doubling time (3.26 d) were both significantly longer than those of peach aphids feeding untreated peppers (12.00 d and 2.30 d) .【Conclusion】CMV significantly inhibited the expressions of MpC002, and then prolongated the developmental duration and decreased the reproduction, which in turn adversely affected its population growth. [ABSTRACT FROM AUTHOR]