Community structure of leaf rollers in longan orchard and litchi orchard

The community structure and the fluctuation of population of leaf rollers in parts of longan orchard and litchi orchard in Guangxi were studied.The results showed that there were altogether 20 species of leaf rollers belonging to 3 families,in which 9 species were not reported as a pest on longan or litchi in the past.There were 16 species of leaf rollers from 3 families in longan orchard,and 17 species of leaf rollers from 2 families in litchi orchard,respectively.The evenness indexes of community in longan orchard and in litchi orchard were 0.2982 and 0.4063,respectively.The results showed that the distributions of number of the different species were not uniform,and a certain species had a very vast number.The diversity index of community in litchi orchard was higher than that in longan orchard.The dominant species in longan orchard was Olethreutes leucaspis Meyrick,and the dominant species in litchi orchard were O.leucaspis Meyrick and Dudua aprobola(Meyrick).The main species in both two orchards were O.leucaspis.D.aprobola and Ebodo cellerigera Meyrick.The population size of leaf rollers in longan orchard was higher than that in litchi orchard.