The Analysis On Key Factors For The Vertical Distribution Of Leaf Miner Liriomyza Sativae Blanchard And The Research On The Behavior Of Its Parasitoid Pnigalio Phragmitis Erd(?)s

The vertical distribution of leaf miner on Phaseolus vulgaris var.humilis Alef was investigated. The differences of the leaves at the different parts of the host plant attracting the leaf miner were detected by using olfactometer. The hair length and density of upper and lower leaves of the host plant were measured. The difference of the content of chlorophyll, total sugar and protein in the different parts of the host plant was determined. The relationship between the characters of different host bean varieties and feeding preference of leaf miner was studied.The behavior of its parasitoid Pnigalio phragmitis Erdos was also studied.The main results are summarized as follow:1.The vertical distribution pattern of leaf miner on the host plant is aggregate. Both of adults and larvae prefer to feed in the lower leaves of the host plant.2.There was no significant difference of secondary substance between upper and lower leaves.3.The difference of the hair length and density of the upper and lower leaves of the host plant is significant, and the hair length and density of the upper leaves are more than that of the lower.4.The difference of the content of chlorophyl in the upper and lower leaves of the host plant is significant, and the content of chlorophyl in the upper leaves is less than the lower.5.The difference of the content of total sugar in the upper and lower leaves of the host plant is significant, and the content of total sugar in the upper leaves is more than the lower.6.The difference of the content of protein in the upper and lower leaves of the host plant is not significant.7.The hair length and density of leaves surface have the greatest effect on the feeding preference. The more of the hair length and density, the less of the feeding of the leaf miner on the host plant. The color of the leaves is decided by the content of chlorophyl. Deeper color leaves can attract more adults. The content of total sugar has a little effect on the leaf miner feed preference, but the content of protein has greater effect on the feeding preference. There is a positive relationship between the feeding preference of leaf miner and the content of the total sugar from its host plant.8.The parasitoid of the leaf miner, Pnigalio phragmitis Erdos, prefers the third instar to parasitizing.