Interspecific correlation between Cephalcia kunyushanica and host plant in natural forest in Kunyushan Mountains, China

In order to determine the propensity of Cephalcia kunyushanica (Hymenoptera: Pamphiliidae) to different forest types (host stand and host-non-host mixture stand) and the interaction between host amount and larvae density of Cephalcia kunyushanica. We investigated the mean insect density and stand types in 50 permanent plots in the Kunyushan Mountains, China. The results showed that seven kinds of pine species were determined as the host of Cephalcia kunyushanica in Kunyushan Mountains. Among the seven species, difference in larvae density was not significant (p > 0.05). Likewise, non-significant difference (p > 0.05) was also found in the mean density of the insects between two kinds of stand types (pure host stand and mixed stand). Strong negative linear relationship between mean insect density and host amounts were found in pure host plots in the year 2013 and 2014. However, non-significant (p > 0.05) correlation was found in host-non-host mixture plots. In addition, in 39 plots investigated, the Shannon-Wiener index (H’) did not change significantly (p > 0.05) in 2008 and 2013, indicating that the resource dilution effect fit the Cephalcia kunyushanica-host model in the Kunyushan Mountains. The current manuscript reports the interaction between the specialist phytophagous insects and the hosts is fit for the resource dilution hypothesis. The result will improve the understanding and operation on the insect-host relationship, as well as the hypothesis could be helpful for us in ecological controlling forest pests.