Adaptability and Heredity Variation of Diamondback Moth Populations under Host Plants Stress
|School||Fujian Agriculture and Forestry University|
|Keywords||Diamondback moth Population differentiation RAPD Host plants Biological characteristics|
Diamondback moth Plutella xylostella (L.) is widely distributed in an important pest of cruciferous vegetables, caused huge losses. With the large-scale use of chemical pesticides, the diamondback moth resistant gradually increased, and the outbreak of the disaster on a global scale. Looking for a more environmentally friendly, more ecological harmonious control of diamondback moth harm is imminent. Six cruciferous vegetables growth, development and reproduction of the diamondback moth, reveals the differences of different host plants on diamondback moth impact, and provide a theoretical basis for the comprehensive prevention and control of the diamondback moth (IPM). In this study, radish, cabbage, kale, mustard greens, flowering cabbage and kale and other cruciferous vegetables host plants. Feeding diamondback moth isolated, closed the same experimental conditions, continuous observation of the 4th generation, 6th generation, the generation of 13 and 11 on behalf of forwarding the main developmental duration of the diamondback moth oviposition period, pupal weight and spawning the amount of biological characteristics. RAPD-PCR molecular marker technology analysis 4th generation, 9 and 15 generations fourth instar larvae of the diamondback moth genomic DNA of different host genetic variation against the diamondback moth, calculated cruciferous vegetables the genetic distance between the generation of diamondback moth host population, and build different host populations of the diamondback moth genetic distance clustering map, analyze the phenomenon of co-evolution between the diamondback moth and host plants and produce population differentiation. The results are as follows: six different host plants on diamondback moth development impact of the duration of the six different host there was a significant difference in duration of the impact of the development of the diamondback moth. Times of the same generation, the developmental duration of the longest diamondback moth on kale; developmental duration of the diamondback moth host populations with feeding on the same host, on behalf of the increase in shortening. Forward main control group (mustard host population) compared to the other five host populations, developmental duration was significantly shorter. Six different host plants of diamondback moth fecundity six cruciferous vegetables host of diamondback moth fecundity there are significant differences. The same generation times, up to the kale host on the fecundity of the diamondback moth, but with the increase of passages, fecundity is the largest decrease; same host, six diamondback moth fecundity radish host on the diamondback moth population growth, the diamondback moth laying eggs on the other five host volume reduced. Forward the main control group (mustard host populations) population fecundity appears to reduce growth phenomenon, while the other five populations. Six different host plants on diamondback moth laying eggs in six different host plants for the duration of the impact on the diamondback moth spawning duration of the impact of significant differences. The same generation times, the diamondback moth oviposition on the kale shortest, but after the forwarding main spawning duration largest increase, much higher than the other five host populations; compared to the same host populations observed, the host 6th generation a reduced growth of (except kale populations). Forward the main, in addition to the minimum amount of growth in the control group (mustard host populations), other populations grow, but the growth of varying magnitudes. Six different host plants on diamondback moth production pupal weight six different host plants on diamondback moth pupal weight difference is significant. Between the times of the same generation, diamondback moth pupal weight difference. The same host populations observed, radish and kale population of diamondback moth pupal weight with the generation of increased mitigate; Forward main host diamondback moth pupae weight average weight gain, weight gain of the control group (mustard populations) amplitude than the other five diamondback moth populations. Six host plant differentiation of the dynamic trend against the diamondback moth. RAPD-PCR technique to study the DNA polymorphism feeding six different cruciferous host plants 4,9,15 generation diamondback moth. 17 primers repeat PCR amplification experiments, NTSYS software statistical analysis of electrophoretic bands to construct a genetic distance matrix and cluster analysis map. The results show that: the diamondback moth feeding kale and five other host population genetic distance (0.6523 to 0.8246), the independent clustered into one; diamondback moth feeding radish genetic distance and cabbage closer to the population (0.3443) , clustered into one, and cabbage, mustard and vegetables heart diamondback moth genetic distance closer successive clustered into one, kale, turnip and cabbage host populations stable regularity with the generation of the increase in population differentiation. Averages and ranges of genetic distance between the host population, the proportion of polymorphic bands of the total number of bands increased with increasing degree of population differentiation with increased deepen.