Volatiles inheriting from Crossostephium chinense act as repellent weapons against aphids in Chrysanthemum lavandulifolium cultivars

Abstract

Chrysanthemum lavandulifolium is a kind of medicinal plant with large industrial scale and widely cultivated in southern China. Chrysanthemum aphids (Macrosiphoniella sanborni) seriously restricted the development of C. lavandulifolium industry. In this study, in order to breed aphid resistant cultivars, we introduced a potential aphid resistant germplasm Crossostephium chinense to participate in breeding, and the role of volatiles in this process was analyzed. Nine true hybrids were obtained by distant hybridization combined with embryo rescue. The aphid resistance and behavioral effects of their volatiles on aphids were tested. All hybrids behaved stronger resistance and repellency than C. lavandulifolium. The repellency of H1, H2 and H11 was significantly higher than other hybrids. Forty-seven major volatiles were detected in the parent and hybrid leaves by using solid phase micro extraction-gas chromatography-mass spectrometry (SPME-GC–MS). H1, H2 and H11 can be separated from other plant materials by PCA analysis, 15 volatiles such as 1, 2-Oxidolinalool were identified as their characteristic difference compounds. Methacrolein was demonstrated to be a repellent compound to aphids by using standard chemical. These findings may lead to novel control strategies against M. sanborni of C. lavandulifolium and its relative species.