TY - EJOU AU - Zhang, Hengdong AU - Huang, Min AU - YingjuanWei, AU - Chen, Jiana AU - Shan, Shuanglü AU - Cao, Fangbo AU - Chen, Guanghui AU - Zou, Yingbin TI - Amylose Content and Starch Granule Size in Rice Grains are Affected By Growing Season T2 - Phyton-International Journal of Experimental Botany PY - 2019 VL - 88 IS - 4 SN - 1851-5657 AB - Amylose content and starch granule size in grains influence rice quality, which differs between the early (ES) and late season (LS). The objective of this study was to determine the variation of amylose content and starch granule size between seasons and find the main reasons (e.g., temperature and solar radiation) for the observed variation. Field experiments with six rice varieties (three high and three low amylose content rice) planted in the ES and LS were conducted in 2016 and 2017, respectively. The mean temperatures during the filling stage were higher in ES, however, the daily temperatures at 7-10 days after flowering (DAF) in 2016, and at 5-10, 13-14 DAF in 2017 were higher in LS. The results showed that amylose content in LS was lower than in ES with high amylose content rice varieties (HACV); the opposite trend occurred with low amylose content rice varieties (LACV). The mean starch granule diameter was higher in LS than ES in 2016, but the opposite result occurred in 2017 with all rice. Our results suggest that higher temperatures increased and decreased the amylose content in HACV and LACV, respectively. Temperatures at 5-15 DAF were important for the formation of starch granules: lower temperatures during 10-14 DAF increased the proportion of larger starch granules (d>6.21 μm, some with d>13.3 μm), and higher temperatures at 5-6 DAF increased the proportion of starch granules with diameter 4.24-6.21 μm. KW - Amylose content; growing season; rice variety; starch granule DO - 10.32604/phyton.2019.07371