Improvements in disease resistance and fruit quality of organic tomato intercropped with living mulch of turfgrass

Living mulch has been adopted in orchard systems and proved effective in disease control and fruit quality improvement. However, no research has tried turfgrass as living mulch for field vegetable crops. In this study, several field experiments were conducted with tomato crops stripe-cultivated with turfgrass and the intercropped tomato crops showed high resistance against leaf blights resulting in improved fruit yield and quality. Lower nitrate concentration in tomato leaves stripe-cultivated with turfgrass might be one of the reasons for decreased risk of fungal infection. Turfgrass root is alive with high activity throughout the year and the root is colonized and mutually benefiting from each other with mycorrhizae. The mycorrhizal colonization was high in turfgrass roots, and also much higher in roots of tomato plants with turfgrass as living mulch than in the tomato plants without living mulch. This might be another reason for decreased infection risk of fungi. In conclusion, as living mulch, an annually ever living turfgrass with its root system colonized by mycorrhizae, making a living soil and improving soil conditions, avoided the infection by soil-borne pathogens in tomato plants that are stripe-cultivated with turfgrass.