水稻种子在不同气候区室温贮藏的适宜含水量及存活特性

The Optimal Moisture Content and Survival Characteristics of Rice Seeds Stored at Six Climatic Zones Under Room Temperature

将不同含水量水平的两个水稻品种幸实(粳稻)和桂朝2号(籼稻)分别贮藏在三亚、南昌、北京、西宁、乌鲁木齐和哈尔滨等6个不同气候类型地区。通过11年的逐年生活力测定,研究了水稻种子室温贮藏的适宜含水量及其存活特性。结果表明,水稻种子经适当干燥后其生活力和活力没有显著下降。但当种子含水量在3.0%以下时种子的生活力和活力受到影响。获得了水稻种子在三亚、南昌室温贮藏时(贮藏温度不是恒定的)的适宜含水量,且适宜含水量5.0%～6.5%具有地域的广适性。相对于其他含水量,适宜含水量种子在贮藏过程中,其生活力快速下降阶段推迟,且适宜含水量上限和极差与贮藏地点年均温和≥0℃积温呈显著或极显著负相关,且适宜含水量下限与之呈显著或极显著正相关。种子在年均温度相同的西宁和乌鲁木齐的贮藏效果不同,≥0℃积温和气候温差波动的差值可能是其主要影响因素。

Rice seeds of two varieties, Guichao 2 （indica） and Sachiminori （japonica） with different levels of moisture content were stored under room temperature at six sites with different types of climatic zones including Sanya, Nanchang, Beijing, Xining, Urumchi and Harbin, respectively. The optimal moisture contents and the survival characteristics were stud- ied through a successive ll-year monitoring on viability and vigor of rice seeds. The viability and vigor of dried rice seeds with optimal moisture content were not significantly declined. However, it proved otherwise when the seed moisture content de- clined to below 3.0%. The optimal moisture content of seeds stored in Sanya and Nanchang at room temperature was ob- tained. The optimal moisture content of 6.5 % to 5.0% was widely adaptable to the six climatic zones. The phase of rapid de- cline in viability of seeds with optimal moisture content was delayed compared with other moisture contents. The upper limit and the range of optimal moisture content were negatively correlated with mean annual temperature and accumulated tempera- ture （ ≥0℃） at significant or highly significant levels, and the lower limit was positively correlated with them at significant or highly significant levels. Although with the same mean annual temperature in Xining and Urumchi, the seed storage results were different. This implied that the accumulated temperature （≥0℃） and fluctuation in temperature were probably the ma jor reasons for the difference.