我国水稻三大优势产区稻米品质现状及区域差异

为全面科学了解我国水稻三大优势产区稻米品质现状及区域差异,采取网格化布局和分层随机抽样方法,于2016—2020年在全国17个水稻主产省的455个重点县抽取5 879份稻谷样品,研究分析了12项品质性状和优质率。结果显示,近5年我国稻米总体优质率为35.96%,粳稻优质率（54.02%）明显高于籼稻（27.30%）,中晚稻优质率（41.43%）显著高于早稻（10.13%）,年度间优质率有变化,2016年为26.86%,2017年为38.30%,2018年为38.61%,2019年为38.79%,2020年为33.33%;区域间优质率差异明显,东北平原为71.38%,显著高于东南沿海的30.83%和长江流域的25.78%。东北三省优质率最高（黑龙江、吉林、辽宁分别为69.65%、75.13%、76.87%）,其次是华南两广（广东37.20%、广西31.92%）、江淮地区（江苏31.88%、安徽34.88%、河南33.57%）和云贵高原（贵州31.16%、云南24.76%）,川渝盆地和湘赣平原优质率有待提升。总体而言,东北平原稻米品质各项指标表现较为适宜,长江流域和东南沿海整精米率低、垩白多,是限制稻米优质率提高的主要因素。整精米率优质达标率总体仅为54.82%,东北平原、长江流域和东南沿海三大优势产区分别为84.59%、47.74%、46.17%,因此,整精米率不仅是我国稻米品质地区差异的关键因子之一,也是今后南方水稻优质育种和栽培的重要攻关目标。

Current Situation and Regional Difference of Rice Grain Quality in Three Rice-Production Superiority Areas of China

To comprehensively and scientifically understand the current situation of rice quality and regional difference of three rice-production superiority areas in China, we collected a total of 5 879 rice samples by grid geographical layout and stratified random sampling from 455 key counties in 17 major rice production provinces of China during 2016—2020, and analyzed 12 quality traits and the ratio of good quality of those samples. The results showed that the ratio of good quality of Chinese rice samples in the past 5 years was 35.96%, the good quality rate of japonica rice（54.02%） was much higher than that of indica rice（27.30%）, and the good quality rate of middle-late rice （41.43%） was significantly higher than that of early rice （10.13%）. There were variations in the ratio of good quality of rice among different years （26.86% in 2016, 38.30% in 2017, 38.61% in 2018, 38.79% in 2019 and 33.33% in 2020）, and the difference of good quality rate among regions was obvious （71.38% in the Northeast Plain, which was significantly higher than 30.83% of the Southeast Coast and 25.78% of the Yangtze River Basin）. Northeast China had the highest ratio of good quality （69.65%, 75.13%, 76.87% in Heilongjiang, Jilin and Liaoning, respectively）, followed by South China （37.20% in Guangdong and 31.92% in Guangxi）, Jianghuai region （31.88% in Jiangsu, 34.88% in Anhui and 33.57% in Henan） and the Yunnan-Guizhou Plateau（31.16% in Guizhou, and 24.76% in Yunnan）, and the ratio of good quality in the Sichuan-Chongqing Basin and the Hunan-Jiangsi Plain still need to be improved. In general, various indicators of rice quality in the Northeast Plain were relatively proper, however, the low head rice rate and high chalkiness degree, which are the dominant factors, limited the ratio of good quality of rice in the Yangtze River Basin and the coast of Southeast China. Only 54.82% of the samples' head rice rate reached the good quality standard, the percentages of big three production superiority areas are 84.59%, 47.74%, and 46.17% respectively. Therefore, head rice rate is one of the key factors of regional difference of rice quality in China, and high head rice rate is considered as an important objective to achieve for good quality rice breeding and cultivation in southern China.