Effects of Feeding on Different Food Plants on the Growth, Development and Biochemical Enzymes of Lymantria dispar

Fed with Salix babylonica, Betula platyphylla, Cedrus deodara, Metasequoia glyptostroboides, Pinus armandii and Acer truncatum, the effects of different food plants on the growth and development of the Lymantria dispar larvae, the activities of enzymes and their gene expression were studied. The results showed that the highest survival rate of the 2^nd instar larvae fed on C. deodara was 55.32%, and the shortest development duration was 5.41 d; the survival rates of S. babylonica and B. platyphylla were 41.34% and 35.71%, and the development duration was 6.40 d and 6.66 d; and the larvae fed on A. truncatum, P. armandii and M. glyptostroboides were significantly lower than that fed on the other plants and could not complete the whole life history. There was a significant difference in the activity of enzymes of the larvae after feeding on different plants. The activities of CarE, AChE, POD and CAT of the larvae after feeding on S. babylonica were significantly higher than those feeding on C. deodara; and the activities of GSTs and SOD of larvae feeding on C. deodara were significantly higher than those feeding on S. babylonica. The activities of GST and SOD were positively correlated with the survival rate and developmental duration of the larvae. The activities of CarE, AChE, POD and CAT were positively correlated with the weight, head width and body length of the larvae. The relative expression levels of LdAChE and LdCAT of larvae feeding on S. babylonica were extremely significantly higher than those in C. deodara, and the relative expression of LdPOD was significantly higher than those in C. deodara, and the expression levels of LdSOD of larvae feeding on C. deodara were extremely significantly higher than those in S. babylonica. The larvae of L. dispar could adjust the biochemical enzyme activity and the expression level of enzyme genes in their bodies with different plant species to meet the needs of their growth and development.