Fig 5.

Effect of applied root exudates from soybean cultivated under different K concentration treatments (a) and of four different species of phenolic acids at four concentrations (b) on the mortality rate of Heterodera glycines. K0, No K application; K1, 1 mM K; K3, 3 mM K; K6, 6 mM K; VA is vanillic acid; FA is ferulic acid; SA is salicylic acid; CA is cinnamic acid. Each histogram represents the mean of four replicates ± SE. Different letters above the bars indicate significant differences (P<0.05) by Duncan’s t-tests.