Salicylic acid promotes endosperm development and heat-tolerance of waxy maize (Zea mays L. var. ceratina Kulesh) under heat stress
Jian Guo,
Zitao Wang,
Jing Li,
Lingling Qu,
Yanping Chen,
Guanghao Li,
Dalei Lu
Affiliations
Jian Guo
Jiangsu Key Laboratory of Crop Genetics and Physiology/Jiangsu Key Laboratory of Crop Cultivation and Physiology/Jiangsu Co-Innovation Center for Modern Production Technology of Grain Crops, Agricultural College of Yangzhou University, Yangzhou 225009, China; Joint International Research Laboratory of Agriculture and Agri-Product Safety of the Ministry of Education, Yangzhou University, Yangzhou 225009, China
Zitao Wang
Jiangsu Key Laboratory of Crop Genetics and Physiology/Jiangsu Key Laboratory of Crop Cultivation and Physiology/Jiangsu Co-Innovation Center for Modern Production Technology of Grain Crops, Agricultural College of Yangzhou University, Yangzhou 225009, China
Jing Li
Jiangsu Key Laboratory of Crop Genetics and Physiology/Jiangsu Key Laboratory of Crop Cultivation and Physiology/Jiangsu Co-Innovation Center for Modern Production Technology of Grain Crops, Agricultural College of Yangzhou University, Yangzhou 225009, China
Lingling Qu
Jiangsu Key Laboratory of Crop Genetics and Physiology/Jiangsu Key Laboratory of Crop Cultivation and Physiology/Jiangsu Co-Innovation Center for Modern Production Technology of Grain Crops, Agricultural College of Yangzhou University, Yangzhou 225009, China
Yanping Chen
Institute of Food Crops, Jiangsu Academy of Agricultural Sciences, Nanjing 210014, China
Guanghao Li
Jiangsu Key Laboratory of Crop Genetics and Physiology/Jiangsu Key Laboratory of Crop Cultivation and Physiology/Jiangsu Co-Innovation Center for Modern Production Technology of Grain Crops, Agricultural College of Yangzhou University, Yangzhou 225009, China; Joint International Research Laboratory of Agriculture and Agri-Product Safety of the Ministry of Education, Yangzhou University, Yangzhou 225009, China
Dalei Lu
Jiangsu Key Laboratory of Crop Genetics and Physiology/Jiangsu Key Laboratory of Crop Cultivation and Physiology/Jiangsu Co-Innovation Center for Modern Production Technology of Grain Crops, Agricultural College of Yangzhou University, Yangzhou 225009, China; Joint International Research Laboratory of Agriculture and Agri-Product Safety of the Ministry of Education, Yangzhou University, Yangzhou 225009, China; Corresponding author.
High temperature (HT) during the grain-filling stage has become an important factor restricting endosperm development and yield formation in maize. Saicylic acid (SA) is an efficient plant-protective hormone, but its specific function and molecular mechanism regulating the heat tolerance of maize grains have not been reported. In this study, two waxy maize varieties cultivated in pots were used as research materials, and exogenous SA and HT were applied at the initial grain-filling stage. Compared with HT, the application of SA prolonged grain-filling duration and increased grain numbers per panicle, thereby improving the grain weight and yield. SA enhanced the ploidy level and promoted the proliferation of endosperm cells under HT. SA promoted the biosynthesis and accumulation of sucrose and starch in endosperm under HT by regulating their metabolism. SA stabilized the balance of endogenous hormones in heat-tolerant variety, and activated the plant hormone signal transduction pathway. SA triggered alpha-linolenic acid metabolism and jasmonic acid signaling pathways of heat-tolerant variety. Furthermore, SA adjusted the phenylpropanoid and flavonoid biosynthesis pathways of heat-sensitive variety. In conclusion, the physiological, biochemical, transcription profile, and metabolite level changes induced by SA treatment form the basis for the enhancement of heat tolerance of maize endosperm.
