Beegum Sahila, Truong Van, Bheemanahalli Raju, Brand David, Reddy Vangimalla, Reddy Kambham Raja
Adaptive Cropping System Laboratory, USDA-ARS, Beltsville, MD, United States.
Nebraska Water Center, Robert B. Daugherty Water for Food Global Institute, University of Nebraska, Lincoln, NE, United States.
Front Plant Sci. 2023 Jul 31;14:1174682. doi: 10.3389/fpls.2023.1174682. eCollection 2023.
Cotton crop is known to be poorly adapted to waterlogging, especially during the early growth stages. Developing functional relationships between crop growth and development parameters and the duration of waterlogging is essential to develop or improve existing cotton crop models for simulating the impact of waterlogging. However, there are only limited experimental studies conducted on cotton specifically aimed at developing the necessary functional relationships required for waterlogging modeling. Further research is needed to understand the effects of waterlogging on cotton crops and improve modeling capabilities in this area. The current study aimed to conduct waterlogging experiments and develop functional relationships between waterlogging and cotton growth and physiology. The experiments were conducted in pots, and the waterlogging was initiated by plugging the drain hole at the bottom of the pot using a wooden peg. In the experiments, eight waterlogging treatments, including the control treatment, were imposed at the vegetative growth stage (15 days after sowing). Control treatment had zero days of water-logged condition; other treatments had 2, 4, 6, 8, 10, 12, and 14 days of waterlogging. It took five days to reach zero oxygen levels and one to two days to return to control after the treatment. After a total treatment duration of 14 days (30 days after sowing), the growth, physiological, reproductive, and nutrient analysis was conducted. All physiological parameters decreased with the number of days of waterlogging. Flavonoid and anthocyanin index increased with increased duration of waterlogging. Photosynthesis and whole plant dry weight in continuously waterlogged conditions were 75% and 78% less compared to 0, and 2-day water-logged plants. Plant height, stem diameter, number of main stem leaves, leaf area, and leaf length also decreased with waterlogging duration. When waterlogging duration increased, leaf, stem, and root macronutrients decreased, while micronutrients showed mixed trends. Based on the experimental study, functional relationships (linear, quadratic, and exponential decay) and waterlogging stress response indices are developed between growth and development parameters and the duration of waterlogging. This can serve as a base for developing or improving process-based cotton models to simulate the impact of waterlogging.
众所周知，棉花作物对涝渍的适应性较差，尤其是在生长早期。建立作物生长发育参数与涝渍持续时间之间的函数关系，对于开发或改进现有的棉花作物模型以模拟涝渍影响至关重要。然而，专门针对棉花进行的旨在建立涝渍建模所需必要函数关系的实验研究非常有限。需要进一步研究以了解涝渍对棉花作物的影响，并提高该领域的建模能力。本研究旨在进行涝渍实验，并建立涝渍与棉花生长和生理之间的函数关系。实验在花盆中进行，通过用木栓堵住花盆底部的排水孔来引发涝渍。在实验中，在营养生长阶段（播种后15天）设置了包括对照处理在内的八种涝渍处理。对照处理的涝渍天数为零；其他处理的涝渍天数分别为2、4、6、8、10、12和14天。处理后需要五天达到零氧水平，处理后一到两天恢复到对照状态。在总共14天（播种后30天）的处理期结束后，进行了生长、生理、生殖和养分分析。所有生理参数均随着涝渍天数的增加而降低。黄酮类化合物和花青素指数随着涝渍持续时间的增加而增加。与未涝渍和涝渍2天的植株相比，持续涝渍条件下的光合作用和全株干重分别减少了75%和78%。株高、茎直径、主茎叶数、叶面积和叶长度也随着涝渍持续时间的增加而降低。当涝渍持续时间增加时，叶片、茎和根中的大量养分减少，而微量养分呈现出混合趋势。基于实验研究，建立了生长发育参数与涝渍持续时间之间的函数关系（线性、二次和指数衰减）以及涝渍胁迫响应指数。这可为开发或改进基于过程的棉花模型以模拟涝渍影响奠定基础。
