缺磷红壤下云南稻核心种质施氮量对抽穗期的影响

Effect of low-nitrogen stress on heading date of the core collection for Yunnan rice landrace under low phosphorus condition

以云南5个稻作区和16个州（市）为单位，在缺磷条件下2种施氮水平对云南稻种核心种质的抽穗期的影响进行了研究。结果表明，云南稻种核心种质具有明显的地理生态分布特点，不同稻区和州（市）的核心种质抽穗期存在较大的差异。在2种处理条件下，基本呈现由北向南逐渐延长的趋势。总体上，云南稻种核心种质在缺磷低氮条件下的抽穗期较缺磷高氮条件下有所延迟，各稻区的相对延迟天数和相对推迟抽穗期相差不大，抽穗期主要体现基因型间的差异。各州（市）2处理间除西双版纳、思茅、临沧、保山4个州（市）有显著或极显著差异外，其余州（市）均无明显差异。

The study was conducted under low- phosphorus and low-nitrogen condition compared with low-phosphorus and high-nitrogen condition on heading date of core collections in 5 rice cropping regions and 16 prefectures of Yunnan , China. The results showed： the heading date of core collection in different rice crop regions and different prefectures presented some biggish difference, and had distinct characters of geography and ecology, it became longer gradually from north to south of Yunnan. In generally, the heading date of the core collection of Yunnan landraee under low-phosphorus and low-nitrogen condition was longer than that of under low-phospborus and high-nitrogen condition, but the dates and the relative delay heading date was not too much between different rice crop regions .The difference of their heading date of all prefectures except Xishuangbanna, Simao, Lineang, and Baoshan was not significant under two treatments mentioned above.