提高水稻的单产,联系着许多因素,如水利、土壤、肥料,合理密植、品种、病虫害防治、气象、耕耘管理等。把它们协调地和合理地运用起来,单位面积产量就会达到一定的高度;而这些因素是各有它独立的积极作用的,如果各项因素运用水平的不断提高,就能不断地索取更高的产量。在各项因素中,品种是一个主体。不同的品种有不同的本性,要求不同的条件,表现不同的生产能力,而一切条件又都是为了满足某个品种的本性以发挥其生产能力的,所以从这个意义来说,品种是各项因素的主体。由此 To improve rice yields, many factors are involved, such as water conservancy, soil, fertilizers, close planting, breeds, pest and disease control, meteorology and cultivation management. By using them in a coordinated and rational manner, the yield per unit area will reach a certain height. Each of these factors has its own positive and independent role. If the level of utilization of each factor is continuously raised, it will be able to continually claim higher Production. Among various factors, variety is a subject. Different breeds have different natures, require different conditions, exhibit different capacities, and all the conditions are in order to satisfy the nature of one breed to exert its productive capacity, so in this sense breeds are all The main factor. thus