Dynamics and Spatial Distribution of Pine Caterpillar′s Natural Enemies

Forestry investigation and data analysis showed that the infection rates of Beauveria bassiana were dependent on the density of Dendrolimus punctatus,the same as parasitoids did.The spatial distribution of cadava and parasitic pupa followed the pattern of their host,scattering or concentrating unevenly,which belonged to negative binomial distribution.The frequent probability curves developed into y =84.82 e(-x/3.30) and y =64.10 e (-x/2.34) respectively.