Fig. 10From: Wheat straw increases the defense response and resistance of watermelon monoculture to Fusarium wiltEffects of wheat straw addition on the content and distribution of lignin in watermelon roots. PAL activity (a) and POD activity (b) in watermelon roots. Cross-sections of the main roots of watermelon at flowering stage, stained with Safranin O (red) and Fast green FCF (green) (c). Arrows indicate the lignin distribution in watermelon roots. Magnification = 4400×. The lignin conent in watermelon roots (d). CK, without adding wheat straw; T1, addition of 1% wheat straw; T2, addition of 2% wheat strawBack to article page