Programmed cell death, antioxidant response and oxidative stress in wheat f lag leaves induced by chemical hybridization agent SQ-1  

作　　者：WANG Shu-ping ZHANG Gai-sheng SONG Qi-lu ZHANG Ying-xin LI Ying GUO Jia-lin CHEN Zheng NIU Na MA Shou-cai WANG Jun-wei 

机构地区：[1]College of Agronomy, Northwest A&F University,National Yangling Agricultural Biotechnology & Breeding Center,Yangling Branch of State Wheat Improvement Centre,Wheat Breeding Engineering Research Center, Ministry of Education,Key Laboratory of Crop Heterosis of Shaanxi Province [2]Institute of Genetics and Developmental Biology, Chinese Academy of Sciences

出　　处：《Journal of Integrative Agriculture》2016年第1期76-86,共11页农业科学学报（英文版）

基　　金：supported by the National High Technology Research and Development Program of China (2011AA10A106);the National Natural Science Foundation of China (31171611, 31371697);the Technological Innovation and Over Planning Projects of Shaanxi Province, China (2014KTZB02-01-02, 2011KTZB02-01-01);the Projects Opening Up New Function of Precision Instrument of Northwest A&F University, China (dysb130210)

摘　　要：Male sterility induced by a chemical hybridization agent （CHA） is an important tool for utilizing crop heterosis. Leaves, especially the flag leaves, as CHA initial recipients play a decisive role in inducing male sterility. To investigate effects of different treatment times of CHA-SQ-1 used, morphological, biochemical and physiological responses of wheat flag leaves were detected in thistudy. CHA induced programmed cell death （PCD） as shown in terminal deoxynucleotidyl transferase-mediated dUTP nick end-labelling （TUNEL） and DNA laddering analysis. In the early phase, CHA-SQ-1 trig- gered organelle changes arid PCD in wheat leaves accompanied by excess production of reactive oxygen species （O2- and H202） and down-regulation of the activities of superoxide dismutase （SOD）, catalase （CAT） and guaiacol peroxidase （POD）. Meanwhile, leaf cell DNAs showed ladder-like patterns on agarose gel, indicating that CHA-SQ-1 led to the activation of the responsible endonuclease. The oxidative stress assays showed that lipid peroxidation was strongly activated and photosynthesis was obviously inhibited in SQ-l-induced leaves. However, CHA contents in wheat leaves gradually reduced along with the time CHA-SQ-1 applied. Young flags returned to an oxidative/antioxidative balance and ultimately developed into mature green leaves. These results provide explanation of the relations between PCD and anther abortion and practical application of CHA for hybrid breeding.Male sterility induced by a chemical hybridization agent （CHA） is an important tool for utilizing crop heterosis. Leaves, especially the flag leaves, as CHA initial recipients play a decisive role in inducing male sterility. To investigate effects of different treatment times of CHA-SQ-1 used, morphological, biochemical and physiological responses of wheat flag leaves were detected in thistudy. CHA induced programmed cell death （PCD） as shown in terminal deoxynucleotidyl transferase-mediated dUTP nick end-labelling （TUNEL） and DNA laddering analysis. In the early phase, CHA-SQ-1 trig- gered organelle changes arid PCD in wheat leaves accompanied by excess production of reactive oxygen species （O2- and H202） and down-regulation of the activities of superoxide dismutase （SOD）, catalase （CAT） and guaiacol peroxidase （POD）. Meanwhile, leaf cell DNAs showed ladder-like patterns on agarose gel, indicating that CHA-SQ-1 led to the activation of the responsible endonuclease. The oxidative stress assays showed that lipid peroxidation was strongly activated and photosynthesis was obviously inhibited in SQ-l-induced leaves. However, CHA contents in wheat leaves gradually reduced along with the time CHA-SQ-1 applied. Young flags returned to an oxidative/antioxidative balance and ultimately developed into mature green leaves. These results provide explanation of the relations between PCD and anther abortion and practical application of CHA for hybrid breeding.

关 键 词：wheat flag leaf chemical hybridization agent SQ-1 programmed cell death antioxidant response oxidative stress 

分 类 号：S512.1[农业科学—作物学]