抄録
Trends in dominant diseases immediately after shifting to lettuce production with or without chemical fertilizers and fungicides, and using conventional or organic cultivation, were investigated in the spring of 2009 to 2011. With organic cultivation, the occurrence of lettuce drop tended to be more severe than with conventional cultivation. Without the application of fungicides, the rates of occurrence of lettuce drop disease in plants cultivated in ultraviolet-absorbing (UVA) film tunnels were lower than in conventional polyolefin film tunnels. UVA film might thus be helpful in controlling this disease in organic cultivation.
