Zhang Xincheng, Fu Liangbo, Tu Yishan, Zhao Huifang, Kuang Liuhui, Zhang Guoping
Department of Agronomy, Key Laboratory of Crop Germplasm Resource of Zhejiang Province, Zhejiang University, Hangzhou 310058, China.
Plants (Basel). 2020 Nov 27;9(12):1663. doi: 10.3390/plants9121663.
Indica-japonica hybrid rice cultivars show great yield potential but poor eating quality and require more nitrogen (N) input relative to japonica rice. However, the effect of N levels on the eating quality of indica-japonica hybrid rice is little known. A field experiment was carried out to investigate the effects of four N levels on two indica-japonica hybrid rice cultivars (Yongyou12 and Yongyou17) differing in eating quality. The results showed that the contents of amylose chains and water-insoluble storage proteins, especially prolamin, increased largely under a high N level, leading to deterioration of the rice-eating quality, although a low N level (100 N kg/ha) had a less negative effect on the eating quality. Moreover, both of the indica-japonica hybrids had high ratios of inferior grains (IG), and the ratio of IG increased with the N level. Grain weight and the immature ratio of IG were reduced and increased with the N level, respectively, which are also factors for deterioration of the eating quality. The two cultivars differed greatly in the responses of eating quality to the N level, with Yongyou17 being more sensitive than Yongyou12. The current results indicated that a high N level deteriorates the eating quality of indica-japonica hybrid rice mainly due to a large increase of IG.
籼粳杂交水稻品种具有巨大的产量潜力，但食味品质较差，且相对于粳稻需要更多的氮投入。然而，氮水平对籼粳杂交水稻食味品质的影响鲜为人知。开展了一项田间试验，以研究4个氮水平对两个食味品质不同的籼粳杂交水稻品种（甬优12和甬优17）的影响。结果表明，尽管低氮水平（100千克氮/公顷）对食味品质的负面影响较小，但在高氮水平下，直链淀粉链和水不溶性贮藏蛋白尤其是醇溶蛋白的含量大幅增加，导致稻米食味品质变差。此外，两个籼粳杂交品种的瘪谷率都很高，且瘪谷率随氮水平的升高而增加。粒重和瘪谷的未成熟率分别随氮水平的升高而降低和升高，这也是食味品质变差的因素。两个品种在食味品质对氮水平的响应上差异很大，甬优17比甬优12更敏感。目前的结果表明，高氮水平会使籼粳杂交水稻的食味品质变差，主要原因是瘪谷率大幅增加。
