Effects of decomposed and undecomposed straw of three crops on clubroot disease of Chinese cabbage and soil nutrients

Aims: Straw turnover plays an important role in reducing soil diseases, improving the ecological environment of plowland and realizing the effective ecological utilization of straw. Methods: Pot and field experiments were carried out to investigate the effects of maize, rice and wheat straws on the growth, clubroot disease of Chinese cabbage and soil nutrients. Undecomposed and decomposed maize, rice and wheat straws were quantitatively added to the monocultural soil of Chinese cabbage, and the crops without straw were taken as the control. Results: The results showed that the addition of maize, wheat and rice straws could promote the growth of monocultural Chinese cabbage, inhibit the occurrence of clubroot disease, increase soil pH value, the content of soil organic matter, alkaline hydrolyzable nitrogen and available potassium in pot experiment. Exogenous straw application could reduce the incidence rate by 22.54 ~ 47.85%, increase the plot yield of field 95.15 ~ 365.81%. Conclusions: In terms of inhibiting clubroot disease and improving soil properties, undecomposed rice straw is superior to maize and wheat straw, while decomposed maize straw is superior to rice and wheat straw.