Does straw returning affect the root rot disease of crops in soil? A systematic review and meta-analysis

Straw returning is a sustainable way that does not destroy soil ecology in agronomic management. Some studies have found that straw returning may aggravate or reduce soilborne diseases in the past few decades. Despite the increasing number of independent studies investigated the effect of straw returning on root rot of crops, the quantitative analysis regarding the relationship between straw returning and crop root rot is still undefined. In this study, keywords co-occurrence matrix was extracted from 2489 published studies (published from 2000 to 2022, the same below) on controlling soilborne diseases of crops. The methods used for soilborne diseases prevention have shifted from chemical to biological and agricultural control since 2010. As root rot is the soilborne disease with the largest weight in keyword co-occurrence according to statistics, we further collected 531 articles focusing on crop root rot. Notably, the 531 studies are mainly distributed in the United States, Canada, China and other countries in Europe and the south and southeast of Asia, and focus on the root rot of soybean, tomato, wheat and other important grain crops or economic crops. Based on the meta-analysis of 534 measurements in 47 previous studies, we explored how 10 management factors (soil pH/texture, type/size of straw, depth/rate/cumulative amount of application, days after application, beneficial/pathogenic microorganism inoculated before application and annual N-fertilizer input) during straw returning affect root rot onset worldwide. The results showed that straw size and microorganisms inoculated before straw returning are the key factors affecting the incidence of root rot. In combination with actual agricultural production, detailed advice applicable to traditional farming system on the optimization management of straw returning was given. This study emphasized the significance of straw pretreatment and farmland management to reduce soilborne diseases during straw returning.