Zhang Yin, Sheng Tian, Shang Liyan, Zhang Beiyou, Jin Long, Hou Fangfang, Harrison Matthew Tom, Huang Liying, Jin Zhaoqiang, Tian Xiaohai, Liu Ke, Shi Shijie, Zhang Yunbo, Li Dayong
Hubei Key Laboratory of Waterlogging Disaster and Agricultural Use of Wetland, College of Agriculture, Yangtze University, Jingzhou 434025, China.
Tasmanian Institute of Agriculture, University of Tasmania, Burnie 7320, Australia.
Plants (Basel). 2025 Jul 18;14(14):2222. doi: 10.3390/plants14142222.
Ratoon rice is a sustainable planting model, and its yield is closely linked to the light and temperature use efficiency. The photothermal quotient (PQ), a key parameter for evaluating the light and temperature use efficiency, significantly influences ratoon rice yield. However, research on how different stubble heights affect PQ and the utilization efficiency of light and temperature resources remains limited. Here, we conducted a two-year field experiment to investigate the radiation use efficiency (RUE), effective accumulated temperature use efficiency (TUE), PQ, interception percentage (IP), intercepted photosynthetically active radiation (IPAR), and total dry weight (TDW) of six ratoon rice varieties under two stubble height treatments (HS: high stubble, LS: low stubble) during the ratoon season. This study aimed to analyze how different stubble heights impact ratoon rice yield by evaluating light and temperature resource utilization efficiency and investigates the relationship between PQ and ratoon rice yield. The results showed that the HS treatment significantly increased ratoon season yield compared to LS treatment, with average yield increases of 21.2% and 28.1% in 2022 and 2023, respectively. This yield enhancement was attributed to improved TDW under HS treatment, driven by increased IP, IPAR, RUE, and TUE. Notably, PQ was significantly lower under HS than under LS treatment. This reduction was primarily attributed to the decreased duration available for light and heat accumulation, consequently lowering PQ. Correlation analysis revealed a significant positive association between main season yield and PQ, while ratoon season yield exhibited a negative correlation with PQ. In conclusion, the HS treatment increased IP and IPAR, enhanced TUE and RUE, and reduced PQ, collectively contributing to higher ratoon season yields. Importantly, our findings indicate that PQ can more effectively predict yield changes in the ratoon season under HS treatment, providing a theoretical basis for optimizing light and temperature resource utilization in ratoon rice.
再生稻是一种可持续种植模式，其产量与光温利用效率密切相关。光热商（PQ）作为评估光温利用效率的关键参数，对再生稻产量有显著影响。然而，关于不同留茬高度如何影响PQ以及光温资源利用效率的研究仍然有限。在此，我们进行了为期两年的田间试验，以研究六个再生稻品种在再生季两种留茬高度处理（HS：高留茬，LS：低留茬）下的辐射利用效率（RUE）、有效积温利用效率（TUE）、PQ、截获率（IP）、截获光合有效辐射（IPAR）和总干重（TDW）。本研究旨在通过评估光温资源利用效率来分析不同留茬高度对再生稻产量的影响，并探究PQ与再生稻产量之间的关系。结果表明，与LS处理相比，HS处理显著提高了再生季产量，2022年和2023年的平均产量分别提高了21.2%和28.1%。产量的提高归因于HS处理下TDW的增加，这是由IP、IPAR、RUE和TUE的增加所驱动的。值得注意的是，HS处理下的PQ显著低于LS处理。这种降低主要归因于光热积累可用持续时间的减少，从而降低了PQ。相关性分析表明，主季产量与PQ之间存在显著正相关，而再生季产量与PQ呈负相关。总之，HS处理增加了IP和IPAR，提高了TUE和RUE，并降低了PQ，共同促成了更高的再生季产量。重要的是，我们的研究结果表明，PQ能够更有效地预测HS处理下再生季的产量变化，为优化再生稻光温资源利用提供了理论依据。
