不同小麦雄性不育类型光合速率的影响因子分析

Analysis on Factors Affecting Photosynthetic Rate in Different Male Sterility Lines of Wheat

【目的】对K、T、V、CHA型不育系及其保持系净光合速率(Pn)与相关生理、环境因子间的关系及变化趋势进行分析研究,以探讨影响不同小麦雄性不育类型光合速率的生理、环境因子。【方法】利用CIRAS-Ⅰ型光合仪对供试材料4个生育时期的旗叶净光合速率及其相关的生理和环境参数(气孔导度Gs、蒸腾速率Tr、水分利用率WUE、光量子通量密度PFD、细胞间隙CO2浓度Ci、大气CO2浓度Ca、叶片温度Ti、大气温度Ta和气孔限制值Ls)进行测定,并采用SAS软件对试验数据进行相关分析、通径分析和回归分析。【结果】Pn、Gs与Tr均在开花期达到最大值,Pn与Gs、Tr的r=0.9305～0.9677、0.8081～0.9068,呈显著(r0.05=0.754)或极显著(r0.01=0.874)正相关。K、T、V型不育胞质对Pn、Gs和WUE产生了不同程度的负向效应,CHA明显降低了Tr,而对WUE无不良影响。从开花期到灌浆期,各不育类型Pn与Gs、Ci的变化趋势相同,与Ls相反,表明其Pn的变化主要受气孔因素限制。K、T、V、CHA不育类型的Pn与其影响因子Gs的通径分析(直接通径系数=0.4943～0.6774)显著,与各因子的回归关系因类型的不同而异,R2=0.965～0.975,经F检验达显著水平。在相同胞质背景下,冀5418的Pn较太911289显著提高1.875～2.703 μmol CO2·m-2·s-1,而在质核间存在不同程度的交互效应。【结论】K、T、V、CHA不育类型Pn最主要的直接影响因子是Gs,Tr、PFD和Ta对K、T型不育系Pn也有较大影响,PFD和Ca对V型不育系Pn的影响显著。Ci是限制CHA型不育系旗叶Pn的另一主要因子,利用构建的回归模型可有效地预测净光合速率的变化。

【Objective】In order to study the factors affecting photosynthetic rate in male sterility lines of wheat,male sterile lines of CHA （chemical hybridizing agent） and cytoplasmic K （Aegilops kotschyi）,T （Triticum timopheevi）,V （Aegilops ventricosa） types of male sterile wheat were compared with their maintainer lines in the dynamic changes of net photosynthetic rate （Pn） and relatively physiologic and environmental factors,which relationship between them were also analyzed. 【Method】 At 4 different developmental stages,CIRAS-Ⅰ was used to record data of flag leaf,including Pn and stomatal conductance （Gs）,transpiration rate （Tr）,water use efficiency （WUE）,photon flux density （PFD）,intercellular CO2 concentration （Ci）,atmospheric CO2 concentration （Ca）,leaf temperature （Ti）,atmospheric temperature （Ta）,stomatal limiting value （Ls）. The data were analyzed by statistical analysis system in order to acquire the results of difference analysis,correlation analysis,path analysis and regression analysis. 【Result】 Pn and Gs,Tr had their most values at anthesis stage. The dynamic changes of Pn was positively correlated with Gs and Tr,and the correlation coefficients were 0.9305^＊＊-0.9677^＊＊,and 0.8081^＊-0.9068^＊＊,respectively （r0.05=0.754,r0.01=0.874）. Cytoplasms of K,T,V-type male sterile had negative effects on Pn,Gs and WUE of flag leaf with different extents. Tr of flag leaf depressed distinctly on account of CHA,but CHA had no significant negative effects on the water use efficiency of wheat flag leaf. As to K,T,V,CHA-type male sterile wheat,the dynamic changes of Pn were the same with Gs and Ci,and were different from Ls,which indicated that the dynamic changes of Pn were restricted by the stomatal factor. Path analysis indicated that different physiological and environmental factors had different effects on 4 types of male sterile wheat. And Gs was the most important effective factor of Pn. And direct path coefficients between Pn and Gs were 0.4943-0.6774,which were all significant. Regression analysis illuminated that R-square were high and regression equation including some important effective factors （Gs,Tr,PFD,Ta etc.） reached significant difference at 0.05 probability level. Compared with the maintainer line Tai 911289,the Pn value of Ji 5418 was significantly higher under the same cytoplasmic background,increased by 1.875-2.703 μmol CO2·m^-2·s^-1,respectively. Interaction values were different under different karyoplasmic background. 【Conclusion】 Gs was the uppermost direct factor affecting Pn of K,T,V,and CHA types. Furthermore,Tr,PFD,and Ta had significant effect on Pn of K,T-type male sterile lines,so did PFD and Ca on Pn of V-type male sterile lines. Chemical hybridizing agent led that Gs and Ci restricted the raise of Pn in CHA-type male sterile lines,which reflected Gs and Ci were the uppermost factors affecting Pn of CHA types. Therefore,the rule of changes of Pn could be estimated effectively with the important physiological and environmental factors hereinbefore.