水稻叶绿素变化与感光性和感温性关系分析

摘 要：【研究目的】水稻叶绿素变化与叶片衰老紧密联系，影响叶绿素变化有高温、强光等因素，但叶绿素变化与感光性和感温性方面的研究很少，本文试图分析这两者间的联系，同时分析叶绿素含量本底与叶绿素变化间的联系。【方法】分别通过35、133个材料在广州和湖北荆州两地多组试验，研究用始穗期在不同生态区的变化，即利用出穗促进率，反映水稻不同材料的感光性和感温性，进一步研究出穗促进率与叶绿素含量变化的关系。此外，对叶绿素含量本底不同的材料，按高低进行分类，探讨不同类型材料叶绿素的变化动态。【结果】在始穗后的第14天到第18天叶片叶绿素含量(SPAD值)减少百分率与出穗促进率呈显著的正相关，35、133个材料分别对应的相关系数是0.5093、0.3036。同时本试验还表明叶绿素含量本底高的材料，在始穗后第9-13天其叶绿素降低幅度较本底低的材料小，而在第14-18天降低幅度反而大，差异达显著水平。叶绿素高低两组材料分开进行出穗促进率与叶绿素含量变化的相关分析，表明低SPAD值组的相关系数更高，达极显著水平。【结论】始穗后第14－18天叶绿素变化与感光性和感温性存在显著相关关系，此期叶绿素变化可以作为反映感光性和感温性的指标。

Correlation between thermo-photoperiodic responsiveness and reduction of leaf chlorophyll content in rice

Abstract [Objective] The chlorophyll content is tightly related to the leaf senescence. High temperature and strong photoperiod affect the variation of chlorophyll content. However, the link between the variation of chlorophyll content and the thermo-photoperiodic responsiveness is yet to be known. Their relationships were analyzed here and the variation of chlorophyll content was also analyzed under different background level. [Method]Two groups with respective 35 and 133 varieties or breeding lines were grown in Guangzhou and Jingzhou, Hubei province. Their heading dates were investigated. The variation percentages in growth duration to heading between two areas were regarded as indicator for their thermo-photoperiodic responsiveness. The chlorophyll content was measured with chlorophyll meter and indicated by SPAD values. [Result] The reduction percentages of SPAD between 14 DAH (days after heading) and 18DAH were found to be positively related to their thermo-photoperiodic responsiveness. The correlative coefficients were respective 0.5093 and 0.3036 in 35 and 133 varieties. We also found that varieties/breeding lines with high background level of chlorophyll content displayed smaller chlorophyll reduction between 9DAH and 13DAH in comparison to those with low background level of chlorophyll content. In contrast, those lines with high background level of chlorophyll content would show bigger chlorophyll reduction between 14 DAH and 18 DAH. [Conclusion]The reduction percentages of SPAD between 14 DAH and 18DAH can be regarded as an indicator of their thermo-photoperiodic responsiveness.