Depth of Stover Layer for Salt Management Influences Sunflower Production in Saline Soils

• Published in: Crop science 2016-07, Vol.56 (4), p.1948-1961
• Main Authors: Zhao, Yonggan, Pang, Huancheng, Wang, Jing, Li, Yuyi, Li, Yan
• Format: Article
• Language: English
• ISSN: 0011-183X; 1435-0653
• DOI: 10.2135/cropsci2015.05.0305

This study aimed to identify the optimal stover layer depth for resolving soil water and salt‐related problems by investigating the effects of the depth of a corn (Zea mays L.) stover layer on soil water, salt distribution, and sunflower (Helianthus annuus L.) yield in the Hetao Irrigation District, Inner Mongolia, China via four treatments: deep tillage without stover (control) and a stover layer (9 Mg ha−1) at depths of 20 (M20), 40 (M40), and 60 cm (M60). Soil water storage was greater with increasing stover depth at planting, and at seedling and budding at 0 to 40 cm deep. The soil water storage of M60 at planting exceeded that of the control by 10% (2013) and 11% (2014). However, M20 and M40 retained less soil water than the control by 7 and 6% at the seedling stage, respectively. Throughout the growth period, M40 had the least salt accumulation and soluble salt concentration at 0 to 40 cm, followed by M20. The greatest seed yield (5680 kg ha−1) and aboveground biomass (18,990 kg ha−1) were obtained with M40 (37 and 49% greater than the control, 16 and 27% greater than M20, and 24 and 38% greater than M60, respectively). M40 produced the greatest economic return (¥39,491 ha−1), 44, 19, and 31% greater than the control, M20 and M60, respectively. Based on soil water storage, salt management, yield, and economic return, 40 cm is an optional depth for burying corn stover for sunflower production in the Hetao Irrigation District and similar areas.