四川省再生稻种植区划初探

PRIMARY RESEARCH ON REGIONAL PLANNING OF RATOON RICE PLANTATION IN SICHUAN

根据1987,1988两年四川省各地再生稻大面积生产结果,结合分析四川省1951～1980年的地面气象资料,从巩固和发展一季杂交中稻——再生稻这一新耕作制度出发,就四川省再生稻合理区域布局作了初步探讨。结果表明:1.两年再生稻单产稳定在75公斤、100公斤以上的县(市),大多分布在盆南长江河谷区,其面积分别占同年全省再生稻面积的67.30％和68.05％,两年单产比区外各县平均高4.92％和17.82％。区内多数县9月上旬平均温度在25℃以上,中旬在22℃以上,下旬在21℃以上。2.研究了四川省盆地内部份县海拔高度对8～10月旬均温回归关系,大约海拔高度每上升100米,8月各旬平均气温下降0.9～1.0℃,9月各旬和10月上旬依次下降0.82、0.58、0.55和0.48℃。回归预测表明,在海拔350米以下的地区9月中旬均温高于22℃的频率较高,这是规划再生稻适宜种植区的一项重要参数。3.以海拔350公尺以下和9月上、中、下旬均温≥25℃、≥22℃、≥21℃为依据,初步规划了当前以汕优63为代表的中迟熟杂交中稻——再生稻的适宜种植区。此外,还讨论了当前规划再生稻适宜种植区的依据,水稻品种改良与适宜区的关系,再生稻与双季稻生产的关系。

On the basis of the results of the production over large area and the research on ratoon rice in Sichuan in 1987 and 1988, combining with the analysis of the surface climatic data of Sichuan from 1951-1980, starting from the developing and the consolidating of the cropping system'medium rice (hybrid rice)---ratoon rice'a rational distribution of the ratoon rice plantation in Sichuan was proposed. The results showed that: 1. The counties (or municipalities) with the grain yield in ratoon rice above 1125 kg/ha, or 1500 kg/ha, in 1987 or 1988 were mostly located in the Yangtse River Valley in the south of Sichuan Basin, whose area for planting the ratoon rice accounted for 67.30% or 68:05% of the total area of the ratoon rice plantation in Sichuan respectively, the average grain yield in these counties was 4.92% or 17.82% higher than that in other counties; the average temperatures of ten-days in September from 1951-1980 in these counties were>25℃ for the first ten-days, >22℃ for the second and>21℃ for the third respectively. 2. The regressions of the average ten-days' temperatures (Y) in August, September and October to the altitude (X) in some counties with the similar latitudes in Siehuan Basin were studied, when the altitude rose about 100M, the average ten-days' temperatures in 'August dropped 0.9-1.0℃, that in September and that of the first ten-days' in October dropped in a progressive decreasing order as 0.82, 0.58, 0.55 and 0.48X1. The regressive forecast showed that, the frequency that the average temperature of the second ten-days in September >22℃ in the region with a altitude below 350 M is higher than that in the region above 350 M. This is an important parameter for the rationable regional planning of the ratoon rice plantation. 3. On the basis of the altitude below 350 M and the average temperatures of the first, second and third ten-days in September≥25℃, 22℃ and 21℃ respectively, the regions suitable to the system 'medium hybrid rice---ratoon rice' plantation taking the medium-late rice cultivar Shanyou 63 as the repre-sentative was primarly planned. The basis for planning the regions suitable to the ratoon rice plantation at present, the relationship between the improvement of rice varieties and the suitable regions, the relationship between the ratoon rice plantation and the double cropping rice production are discussed also in this paper.