【摘要】 为了探索增加小麦穗粒数的途径,我们连续两年(76—77年)研究了小麦小花分化和退化的规律,以及氮肥施用水平对它的影响。1978年进一步研究了碳氮代谢在体内代谢的协调以及与小花分化和退化的关系,为提高穗粒数提供理论依据。更多还原

【Abstract】 A 3—year study on the relationship between floret development and theapplication of nitrogen fertilizer in different levels was conducted for win-ter wheat from 1975 to 1978 in Beijing.The results obtained are summa-rized as follows:1.The determining process of grain number in spikes of wheat plant canbe divided into three phases:(1)Differentiation phase of floret;(2)Pola-rized phase of floret development;(3)Phase of flowering and seed-setting.2.The total number of floret is relatively stable in the same region everyyear.The quantity and the time of application of nitrogen fertilizer inspring has no significant effect on the total number.3.During the polarized phase of floret development(from the expansionof flag leaf to flowering),large number floret degenerated.A higher rateof formative floret depends upon an appropriate nitrogen content and asuitable carbon-nitrogen ratio in the wheat plants.4.The normal morphological florets still degenerated partially in the pha-se of flowering and seed-setting.The percentage of fructification of theseflorets is determined by the sugar content in the plants and the sheathsthrough the expansion of flag leaf to the heading stage.5.An unity of the rate of formative florets and the rate of fructificationreached through the regulation of the sugar and nitrogen content in wheatplant,might be the key to the increment in grain number per spike.更多还原