Seasonal water-heat-salt dynamics in coastal salinized fields: impacts on cotton photosynthesis and yield

作者：Feng Guoyi, Qian Zhang, Yan Wang, Ming Dong, Shulin Wang, Zhe Wu, Hong Qi · 发表于：Frontiers in Plant Science · 年份：2025 · DOI：10.3389/fpls.2025.1600293 · 被引用次数：6 · 研究领域：Research in Cotton Cultivation、Irrigation Practices and Water Management、Plant responses to water stress

Introduction: Soil moisture, temperature, and salinity critically constrain cotton production in saline soils. Understanding how cotton photosynthetic characteristics and yield respond to seasonal water-heat-salt dynamics is essential for improving management practices in these challenging environments. Methods: A two-year field study (2015-2016) was conducted comparing cotton growth, photosynthetic characteristics, and yield in mildly, moderately, and severely salinized fields. Seasonal soil water-salt dynamics in the 0-200 cm layer were monitored. Results: seasonal rainfall and temperature fluctuations significantly influenced soil water-salt dynamics in the 0-140 cm layer. During spring (April-May), drought maintained soil salinity above 3 g/kg, while low temperatures delayed cotton germination by over a day. In rainy season (July-August), rainfall leached salts from topsoil (0-40 cm), reducing salinity to below 5 g/kg and alleviating salt stress. Mildly saline fields exhibited superior photosynthetic performance, with leaf area index, chlorophyll content, and canopy photosynthetic rate being 1.2-1.5 times higher than in moderate/severe fields. These fields also showed extended "source-sink" organ development periods (16-28 days for "source," 4-24 days for "sink") and 13.8%-18.8% greater boll weight, ultimately achieving a seed cotton yield of 3,303 kg/ha-34.3%-120.7% higher than yields from moderate/severe fields. Discussion: Our results indicate that excessive soil salin...