2021年盐都区水稻灌浆结实期灾情调查及成因分析

Investigation of the Causes of Rice Production Losses in the Grain Filling Stage in Yandu District in 2021

2021年盐都区水稻灌浆结实后期出现了大范围倒伏、穗发芽及裂壳等现象,严重影响水稻产量与品质。根据盐都区气象局、盐都区农业农村局及保险公司3部门联合调查资料及盐都区气象局提供的气象资料,分析了灾害发生的原因。调查结果显示:2021年全区水稻倒伏面积约1.224万hm^(2),占水稻总面积的40%左右,倒伏最严重的品种是金粳818,其次是南粳9108,倒伏最轻的品种是南粳5718;休眠性较弱的品种南粳5718、淮稻5号等穗发芽严重,休眠性强的品种南粳9108、扬农稻1号等穗发芽较轻;少量品种出现了裂壳现象,以丰粳908裂壳最为严重,几乎全部裂开,南粳5718、淮稻5号等裂壳较少。2021年水稻生长前期气候条件适宜,水稻生长发育良好,但灌浆结实期气温偏高,导致灌浆速率加快,成熟期有所提前,灌浆后期又遭受暴雨、大风、连阴雨等灾害性天气,加上部分时段管理不到位等因素的共同作用,导致水稻大面积受灾。

In 2021, severe rice production damage occurred in Yandu District, Yancheng City, consisting of a large-scale lodging,pre-harvest sprouting, and shell cracking in the late grain filling stage, which seriously reduced rice yield and grain quality. This study analyzed the causes of the damage based on the results of the joint investigation of Yandu Meteorological Bureau, Yandu Bureau of Agricultural and Rural Affairs, and the insurance company, as well as the meteorological data provided by Yandu Meteorological Bureau. The investigation results showed that in 2021, rice lodging area in the whole Yandu Districtwas about 12 240 hectares,accounting for about 40% of the total rice-planting area. Among all planted varieties, Jingeng 818 showed the severest lodging,followed by Nangeng 9108, while Nangeng 5718 displayed the lightest. Furthermore, pre-harvest sprouting occurred on some varieties,which was serious on Nangeng 5718 and Huaidao No.5 that have weak seed dormancy trait, but lighter on Nangeng 9108 and Yangnongdao No.1 that have stronger seed dormancy trait. Furthermore, shell cracking occurred on a small number of varieties to different degrees, which was the severest on Fenggeng 908 with almost all seed shells cracking, but slight on Nangeng 5718 and Huaidao No.5. Our analysis revealed that in the early stage of rice growth in 2021, the climatic conditions were suitable for rice development;however, the temperature in the grain filling stage was relatively higher, leading to accelerated filling and an advanced maturity stage. Also, in the late stage of grain filling, rice growth and development was affected by disastrous weather comprising rainstorm, gale, and an unbroken spell of wet weather, which was coupled with other factors such as inadequate field management in some periods. The above factors collectively resulted in the substantial rice production losses on a large scale.