Abstract:

To explore the reasons of cucumber plant infected with root-knot nematodes (RKNs), the effects of RKNs on the related characters of water potentials in the root and shoot of cucumber plant were studied through artificial inoculation. The results showed that, after RKNs infection, water potential in the root and shoot as well as shoot diameter of cucumber plant decreased. Soluble protein content in the root and shoot, as well as soluble sugar content in the shoot all rose significantly when inoculation rate was 6000 eggs per plant. Root activities increased slightly when the inoculation rate was 2000 eggs per plant, and then it reduced gradually with increased inoculation rate. Water potential in the shoot was significantly correlated with only root activities and shoot diameter. In contrast, significant correlations between water potential in the root and all the other indexes except for soluble sugar in the root were observed. Decrease in root activities and shoot diameter and excessive osmotic regulation in the root were the main reasons for water deficit in the root and shoot of cucumber plant infected with RKNs.