Expression of a rice soluble starch synthase gene in transgenic wheat improves the grain yield under heat stress conditions

• Published in: In vitro cellular & developmental biology. Plant Vol. 54; no. 3; pp. 216 - 227
• Main Authors: Tian, Bin, Talukder, Shyamal K., Fu, Jianming, Fritz, Allan K., Trick, Harold N.
• Format: Journal Article
• Language: English
• Published: New York Springer Science + Business Media, LLC (Springer) 01.06.2018; Springer US; Springer Nature B.V
• Subjects: Agricultural production; Biomedical and Life Sciences; Biosynthesis; BIOTECHNOLOGY; Cell Biology; Climate change; Crop production; Crop yield; Crops; Deactivation; Deoxyribonucleic acid; Developmental Biology; DNA; Endosperm; Enzymes; filling period; Gene expression; Genes; Genetic transformation; Genetically altered foods; Glucose; Grain; grain yield; Heat stress; Heat tolerance; High temperature; in vitro studies; Inactivation; Life Sciences; Photosynthesis; Plant Breeding/Biotechnology; Plant Genetics and Genomics; Plant Sciences; promoter regions; Proteins; Rice; Seeds; Starch; Starch synthase; temperature; Transgenic plants; Triticum aestivum; Weight; Wheat; Yield; Heat stress; Thermotolerance; Starch synthesis; Wheat transformation
• ISSN: 1054-5476; 1475-2689
• DOI: 10.1007/s11627-018-9893-2

Wheat (Triticum aestivum L.) is a temperate cereal with an optimum temperature range of 15–22°C during the grain filling stage. Heat stress is one of the major environmental constraints for wheat production worldwide. Temperatures above 25°C during the grain filling stage significantly reduced wheat yield and quality. This reduction was reported due to the inactivation of the soluble starch synthase, a key heat-labile enzyme in starch transformation of wheat endosperm. To improve wheat productivity under heat stress, the rice soluble starch synthase I, under the control of either a constitutive promoter or an endosperm-specific promoter, was expressed in wheat and the transgenic lines were monitored for expression and the effects on yield-related traits. The results showed that the transgenic wheat events expressed rice soluble starch synthase I at a high level after four generations, and transgenic plants produced grains of greater weight during heat stress. Under heat stress conditions, the thousand kernel weight increased 21–34% in T2 and T3 transgenic plants compared to the non-transgenic control plants. In addition, the photosynthetic duration of transgenic wheat was longer than in non-transgenic controls. This study demonstrated that the engineering of a heat tolerant soluble starch synthase gene can be a potential strategy to improve wheat yield under heat stress conditions.