Strip tillage promotes crop yield in comparison with no tillage based on a meta-analysis

Conservation tillage (e.g. no tillage, minimum tillage) is regarded as an effective way to maintain sustainable crop productivity and improve soil quality globally. However, the claim that conservation tillage could improve crop yield are still controversial. It is hypothesized that whether conservation tillage increase crop yield in comparison with conventional tillage (CT) depends on the different conservation tillage practices, for example, no tillage (NT) and strip tillage (ST), and different variables including in agronomic managements, climate conditions, and soil properties. Herein, a meta-analysis was conducted to evaluate how tillage practices affect crop yield and which factors dominate yield performance mostly. Based on the 53 published articles with 290 paired-comparisons across the world, the effects of ST vs. CT and ST vs. NT on crop yield were conducted. It was showed that crop yield under ST had an increasing trend compared to that under CT and NT. Especially, ST significantly increased crop yield by 4.81% in contrast with NT, which indicated that ST might be a promising practice of conservation tillage in terms of crop yield. Under the agronomic managements of continuous cropping, multiple cropping, graminaceous crops, and straw removing, ST significantly increased crop yields by 5.40%, 10.29%, 7.66%, and 7.60% compared to NT, respectively. ST achieved significantly higher crop yield by 5.68% on average and 11.63% as compared to NT under all soil texture and neutral soil. Concerning the climate conditions, crop yield significantly increased by 3.64% under ST as compared to NT in cooler area where mean annual temperature (MAT) was lower than 10°C. Importance analysis indicated that cropping system and MAT were the key factors affecting the performance of tillage practice on crop yield. Overall, present study revealed that ST might be a favorable conservation tillage practice in continuous and multiple cropping systems with graminaceous crop (e.g. maize) in cooler (MAT <10℃) region in terms of yield promotion. This meta-analysis study demonstrated the importance of conservation tillage optimization for food safety and sustainable development of agriculture.