Barley genotype expressing 鈥渟tay-green鈥?like characteristics maintains starch quality of the grain during water stress condition

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• 作者：Peter W. Gous ; Jovin Hasjim ; Jerome Franckowiak ; Glen P. Fox ; Robert G. Gilbert
• 关键词：Barley ; Water stress ; Starch structure ; Molecular structural characterisation
• 刊名：Journal of Cereal Science
• 出版年：November, 2013
• 年：2013
• 卷：58
• 期：3
• 页码：414-419
• 全文大小：683 K

文摘

The identification of 鈥渟tay-green鈥?in sorghum and its positive correlation with yield increases has encouraged attempts to incorporate 鈥渟tay-green鈥?like traits into the genomes of other commercially important cereal crops. However, knowledge on the effects of 鈥渟tay-green鈥?expression on grain quality under extreme physiological stress is limited. This study examines impacts of 鈥渟tay-green鈥?like expression on starch biosynthesis in barley (Hordeum vulgare L.) grain under mild, severe, and acute water stress conditions induced at anthesis. The proportions of long amylopectin branches and amylose branches in the grain of Flagship (a cultivar without 鈥渟tay-green鈥?like characteristics) were higher at low water stress, suggesting that water stress affects starch biosynthesis in grain, probably due to early termination of grain fill. The changes in long branches can affect starch properties, such as the rates of enzymatic degradation, and hence its nutritional value. By contrast, grain from the 鈥渟tay-green鈥?like cultivar (ND24260) did not show variation in starch molecular structure under the different water stress levels. The results indicate that the cultivar with 鈥渟tay-green鈥?like traits has a greater potential to maintain starch biosynthesis and quality in grain during drought conditions, making the 鈥渟tay-green鈥?like traits potentially useful in ensuring food security.