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The tea tussock moth (Euproctis pseudoconspersa) is one of the most destructive chewing pests in tea plantations and causes a serious allergic reaction on the skin of tea plantation workers. The sex pheromone components of its Japanese population were first identified as 10,14-dimethylpentadecyl isobutyrate (10Me14Me-15:iBu) and 14-methylpentadecyl isobutyrate (14Me-15:iBu), with a stereogenic center. Only 10Me14Me-15:iBu has been identified in the Chinese E. pseudoconspersa population. However, field tests have shown that 10Me14Me-15:iBu cannot meet the demand of effective pest control in China. To develop a high-efficiency E. pseudoconspersa sex pheromone formula, electroantennogram (EAG) recordings of (S)- and (R)-enantiomers of 10Me14Me-15:iBu and 14Me-15:iBu were obtained in the present study. The results demonstrated that the EAG responses of male antennae to (R)-enantiomers were significantly higher than responses to the (S)-enantiomers, and 14Me-15:iBu also elicited EAG activity. Field tests showed that the catch numbers of male moths by (R)-enantiomers were significantly higher (P

The normalization of quantitative real-time PCR (qPCR) is important to obtain accurate gene expression data, and the most common method for qPCR normalization is to use reference genes. However, reference genes can be regulated under different conditions. qPCR has recently been used for gene expression study in Laodelphax striatellus, but there is no study on validation of the reference genes. In this study, five new housekeeping genes (LstrTUB1, LstrTUB2, LstrTUB3, LstrARF and LstrRPL9) in L. striatellus were cloned and deposited in the GenBank with accession numbers of JF728809, JF728810, JF728811, JF728807 and JF728806, respectively. Furthermore, mRNA expressions of the five genes and β-actin were measured by qPCR with insect samples of different instar at nymph stage, and the expression stabilities were determined by the software geNorm and NormFinder. As a result, ARF and RPL9 were consistently more stable than β-actin, while three TUB genes were less stable than β-actin. To determine the optimal number of reference genes used in qPCR, a pairwise variations analysis by geNorm indicated that two references ARF and RPL9 were required to obtain the accurate quantification. These results were further confirmed by the validation qPCR experiment with chitinase gene as the target gene, in which the standard error of the mRNA quantification by using binary reference ARF-RPL9 was much lower than those by ARF, RPL9 or β-actin alone. Taken together, our study suggested that the combination of ARF-RPL9 could replace β-actin as the reference genes for qPCR in L. striatellus.