Influence of amino acids and glucosinolates in three Brassicaceae vegetable plants on preference and performance of the green peach aphid: Myzus persicae
The green peach aphid, Myzus persicae (Sulzer) is a generalist pest of various host plants, whose feeding preference and growth performance mainly depends on the quantity and quality of nutrients and defensive metabolites in host plants. Here, we studied the preference and performance of M. persicae on three major Brassicaceae vegetables in China and measured nutrient (amino acids) and defensive (glucosinolates) metabolites in these plants. We found that M. persicae preferred and performed better on Chinese cabbage than cabbage and radish, which may be due to the relatively higher concentration of amino acids and lower levels of glucosinolates in their leaves. The glucosinolates level in cabbage leaves was ten times higher than the other two plants, while the amino acid concentration in radish was only half of the cabbage or Chinese cabbage. The higher concentration of glucosinolates in cabbage and lower levels of amino acids in radish may account for the poorer preference and growth of M. persicae on these two plants. These results suggest that both amino acids and glucosinolates in plants are important determinants of the preference and performance of M. persicae, which provide new knowledge for the cultivation and breeding of Brassicaceae vegetables.