Effects of inhibition of starch branching enzymes on starch ordered structure and component accumulation in developing kernels of rice. (January 2020)

• Record Type: Journal Article
• Authors: Lin, Lingshang; Huang, Jun; Zhang, Long; Liu, Qiaoquan; Wei, Cunxu
• Is Part Of: Journal of cereal science. Volume 91(2020)
• Publication Date: 2020-01
• Subjects: Rice developing kernel -- Starch branching enzyme -- Starch component accumulation -- Starch ordered structure; Grain -- Periodicals; Cereal products -- Periodicals; Céréales -- Périodiques; Produits céréaliers -- Périodiques; Cereal products; Grain; Periodicals; 664.705
• DOI: 10.1016/j.jcs.2019.102884
• Languages: English
• ISSNs: 0733-5210

Abstract

Abstract: Three rice varieties, Te-qing (TQ), Wu-xiang 9915 (WX) and Guang-ling-xiang-nuo (GLXN) with different amylose contents, and their derived lines with inhibition of starch branching enzyme I and IIb (SBEI/IIb) (GLXN-, WX- and TQ-SBEI/IIb – ) were used to investigate and compare the starch ordered structure and component accumulation in developing kernels. The starches in developing kernels of TQ, WX and GLXN all showed a typical A-type crystallinity and had similar short-range ordered structure, but their relative crystallinities gradually decreased in TQ and WX and had no significant change in GLXN with kernel development. For wild-type rices, starch components gradually increased in developing kernels. With inhibition of SBEI/IIb, the accumulation of amylose and amylopectin long branch-chains in kernels was slightly affected, but amylopectin short branch-chains seriously decreased, resulting in a significantly lower dry weight and starch content in kernel. The B-type crystallinity in developing starch gradually accumulated with kernel development of TQ-, Wx- and GLXN-SBEI/IIb – lines. The inhibition of SBEI/IIb decreased the relative crystallinity but increased the short-range ordered structure of starches. The effects of inhibition of SBEI/IIb on starch ordered structure and component accumulation mainly appeared after 10 days after flowering, and were the most conspicuous for indica rice TQ. Though the inhibition of SBEI/IIb influenced the ordered structure and component accumulation of starch, the starch content and components in developing kernels all showed significantly positive correlations with kernel dry weight. Graphical abstract: Image 1 Highlights: Starch branching enzyme I and IIb (SBEI/IIb) were inhibited in three rice varieties. B-type crystallinity gradually accumulated in SBEI/IIb – line with kernel development. The inhibition of SBEI/IIb increased the short-range ordered structure of starches. The effects of inhibiting SBEI/IIb on developing starch mainly appeared after 10 DAF. The decreased AP-S was responsible for the lower weight and starch content in kernel.