Effects of biochar and Trichoderma pseudokoningii on the growth of cucumber seedlings and control effect against Fusarium wilt
To study the control effect of exogenous substances on cucumber Fusarium wilt,biochar and Tri-choderma pseudokoningii were used to determine the effects of different treatments on cucumber seedling growth,rhizosphere soil enzyme activity,leaf antioxidant enzyme activity,and control efficiency against cucumber Fusarium wilt through pot experiments.The results showed that both biochar and Trichoderma pseudokoningii improved the quality of cucumber seedlings,increased enzyme activity in rhizosphere soil and leaf protective enzyme activity,and enhanced the control effect on Fusarium wilt disease.Among them,B1T3(1×104 cfu·g-1 Fusarium oxysporum powder+40 g·kg-1 biochar+1 ×106 cfu·g-1 Trichoderma pseudokoningii)was the best.Thirty days after cucumber sowing,the activities of sucrase,urease,alkaline phosphatase and protease in the rhizosphere soil of B1T3 were significantly higher than those of other treatments,with 137.44%,143.05%,139.84%,and 180.00%higher than those of CK(1×104 cfu·g-1 Fusarium oxysporum powder),respectively.The activities of superoxide dismutase,ascorbic acid peroxidase,catalase,and peroxidase in the leaves of B1T3 cucumber seedlings were 75.67%,97.32%,71.95%,and 146.06%higher than those of CK,respectively.The height,stem diameter,root shoot ratio,and strong seedling index of B1T3 cucumber seedlings were 86.30%,107.91%,162.50%,and 228.57%higher than those of CK,respectively.The control effect of potted cucumber wilt disease during seedling stage reached 91.21%.Research has shown that biochar and Trichoderma pseudokoningii enhance the antioxidant enzyme activity and rhizo-sphere soil enzyme activity of cucumber seedlings,promote seedling morphogenesis and material accumulation,and improve the control effect of cucumber wilt disease.