氮肥水平对粳稻数量性状遗传力的影响

EFFECTS OF NITROGEN LEVELS ON THE HERITABILITIES OF QUANTITATIVE CHARACTERS IN SINICA RICE

选取10个有代表性的粳稻品种,设置4个氮肥水平,用3次重复的裂区设计,研究了粳稻数量性状遗传力与氮肥水平的关系。结果表明:氮肥水平不仅影响一些重要性状的表现型,还影响其遗传力。不同性状的遗传力对氮肥水平的响应度和响应模式有别,生育期的响应度很低,每穗总粒数和千粒重相对较低,其余性状则较高。随着氮肥水平的提高,株高和千粒重的遗传力有线性降低的趋势,而分蘖力、成穗率、结实率和籽粒产量的遗传力有线性增加的趋势。因此,在粳稻育种中,应将育种材料置于能使性状遗传力达最大值的合适氮肥水平下,以利提高育种效率或选择效果。

In stadying the heritabitities of quantitative characters of sinica rice at varying levels of nitrogen fertilizer and their relations with the levels of nitrogen, 10 typical, sinica varieties were chosen, 4 levels of nitrogen were estabished and the split-plot design with 3 replications were adopted. The results indicated that:The nitrogen levels did affect not only the phenotypes but also the heritabilities of some important characters. The degree and the model of response of heritability to nityogen levels were varying with the characters. The degree of response for growth duration was very low, those for total spikelet number per panicle and 1000-grain weight were relatively lower, but those for other characters were camparatively high. As the nitrogen levels increased, the heritabilities of plant height and 1000-grain weight had the tendency to decrease, while those of tillering capacity, effective tiller percentage, ferile spikelet percentage and grain yield trended toward increase. Therefore, the breeding materials of sinica rice shoudd be subjected to manipulation or selection at aproper nitroger level which can cause the heritability to get the maximum value.