Straw returning is a widely adopted agronomic practice for soil improvement, yet its impact on crop health, particularly its influence on different types of pathogens and pests, remains inadequately understood. While the benefits for soil fertility are recognized, a systematic evaluation of how specific management modes affect both biotic stresses and yield in dryland maize systems is lacking.
Here, long-term fixed-field experiments were conducted. The primary treatments compared spring straw returning and autumn straw returning. Secondary treatments investigated three returning depths (15, 30, and 45 cm) and two returning amounts (half and full). We comprehensively assessed the effects of these factors on the disease indices (DI) of northern leaf blight and ear rot, the damage rate by O. furnacalis, and final grain yield.
The key results demonstrated distinct patterns: For northern leaf blight (an airborne disease), autumn returning reduced the DI by 12.24% compared to spring returning. Furthermore, under spring returning, half-amount returning showed a 13.32% lower DI than full-amount returning. For ear rot (a soil-borne disease), spring returning was more effective in reducing its DI than autumn returning. A deeper returning depth of 45 cm significantly lowered the ear rot DI by 30.43% compared to 15 cm, and full-amount returning was slightly more effective than half-amount. Regarding O. furnacalis (an overwintering soil pest), spring returning reduced its damage rate by 21.64% compared to autumn returning, and a depth of 45 cm achieved a 51.82% reduction compared to 15 cm, with returning amount having no significant effect. In terms of yield, the combination of full-amount and autumn returning was most beneficial, and a returning depth of 30 cm optimized productivity.
Therefore, this work establishes that straw management can be strategically tuned for targeted pest and disease mitigation. Autumn returning with a reduced amount is recommended to suppress airborne diseases like northern leaf blight, whereas spring returning at a greater depth (30-45 cm) is more effective against soil-borne ear rot and overwintering pests like O. furnacalis. These findings provide a nuanced agronomic framework for optimizing straw returning practices to enhance both crop protection and yield in dryland maize systems.
The work entitled “Effects of straw returning modes on the occurrence of major pests and yield of maize in dryland” was published on Journal of Shanxi Agricultural Sciences (published on Aug. 05, 2025).
DOI： 10.26942/j.cnki.issn.1002-2481.2025.05.04.