基于红外热图像的棉花花铃期CWSI与光合参数关系的研究

Research on relationship of CWSI and photosynthetic parametersduring flowering and boll-forming stage of cotton based on infrared thermograph

在新疆生态气候条件下，采用膜下滴灌植棉技术，利用Fluke红外热像仪获取新陆早13号和新陆早33号两棉花品种在1050m3／hm2，2100m3／hm2，4200m3／hm2，5300m3／hm24水平水分处理条件下花铃期冠层红外热图像；应用图像处理技术，提取棉花冠层受光叶片温度，将人工参考湿表面（WARS）的温度运用到Jones（1992）定义的水分胁迫指数（CWSI）的经验公式中，计算CWSI；同时，用LI一6400便携式光合仪测得相应叶片净光合速率（Ph）、气孔导度（Gs）和蒸腾速率（Tr），研究花铃期棉花冠层不同程度水分CWSI与尸n、岱和n的相关性。结果表明，水分胁迫下随砌、岛和开的降低，CWSI升高，CWSI的临界值应在0．37—0．40。水分胁迫与非水分胁迫间，棉花冠层CWSI存在显著性的差异（а=0．05），水分胁迫下CWSI值较高；花铃期CWSl分别与砌、白和n显著负相关（RGcws1-Pn=一0．8533＊＊，Rcws1一Gs=一0．7771＊＊，Rcws1，一Tr=一0．8063＊＊），花铃期CWSI与Pn、岱和乃可同步反映棉花冠层的水分状况。

Using Fluke infrared thermal camera the canopy infrared thermal images at flowering and boll-forming stage of cotton under film drip irrigation experiment of 2 cotton cultivars with 4 levels water treatments in North of Xin- jiang was obtained. Based on the image processing technology the temperature of canopy sunlit leaves was acquired. For calculation of CWSI the wet artificial reference surface （WARS） temperature was used in empirical formulation defined by Jones （1992）. Using LI - 6400 portable photosynthesis system the data of the corresponding net Photosynthetic Rate （Pn）, Stomatal Conductance （ Gs ） and Transpiration Rate （Tr） were obtained for studying the correlation between CWSI and Pn, Gs and Tr in different level water treatments during flowering and boll-forming stage of cotton canopy. The result showed that under water stress CWSI increased with Pn, Gs and Tr reduction. CWSI threshold should be 0.37 to 0.40. CWSI was significantly difference （a = 0.05） in water-stressed, treatment and non water-stressed treat- ment. CWSI was higher in water-stressed treatment. The relationship between CWSI and Pn, Gs and Tr was significant- ly negative correlated （ Rcws1- Pn = - O. 8533 ＊＊ , RCWSl - Gs = - O. 7771 ＊＊ , Rcwst- Tr = - O. 8063 ＊ ＊ ）. CWSI as well Pn, Gs and Tr can synchronously reflect drought stress of cotton canopy.