协青早B//协青早B/东乡野生稻BC1F9群体低磷耐性鉴定及其生理机制

通过水培法对协青早B//协青早B/东乡野生稻BC₁F₉群体221个株系低磷耐性进行了鉴定，测定了株高、叶龄、黄叶数、地上部干物质量等形态指标及丙二醛（MDA）、可溶性糖和地上部磷含量等生理指标，计算了磷效率，并对各指标间相关性进行了分析.结果表明：221个株系的7个指标均显示出差异性，耐性株系在低磷胁迫下表现为相对叶龄、相对株高、相对地上部干物质量和相对可溶性糖含量较高，相对黄叶数和相对MDA含量较低，相对地上部磷含量差异不明显；磷效率与磷利用效率和磷吸收效率均呈正相关，其中磷利用效率与磷效率达到极显著水平（P<0.01），表明东乡野生稻回交重组自交系中耐性株系低磷耐性原因主要是具有高磷利用效率，即其单位吸磷量干物质合成力较高.

Low-phosphorus tolerance and related physiological mechanism of Xieqingzao B//Xieqingzao B/Dongxiang wild rice BC1F9 populations.

By the method of water culture, the low-phosphorus tolerance of 221 lines of Xieqingzao B//Xieqingzao B/Dongxiang wild rice BC₁F₉ populations was indentified. The morphological indices including plant height, leaf age, yellow leaf number, and shoot dry mass as well as the physiological indices including MDA, soluble sugar, and shoot phosphorus content were measured, also, the phosphorus efficiency was calculated, and the correlations among the indices were analyzed. All the 221 lines had differences in the seven test indices, and the low-phosphorus tolerance lines under low-phosphorus stress had higher values of relative leaf age, relative plant height, relative shoot dry mass, and relative soluble sugar content, but lower values of relative yellow leaf number and relative malondialdehyde content. The relative shoot phosphorus content had less difference. Phosphorus efficiency was positively correlated with phosphorus utilizationefficiency and phosphorus uptake efficiency, and the correlation between phosphorus efficiency and phosphorus utilization efficiency was at significant level (P<0.01), suggesting that the low-phosphorus tolerance capability of the low-phosphorus tolerance lines was mainly attributed to the high phosphorus utilization efficiency of the lines, namely, low-phosphorus tolerance lines had stronger capability in synthesizing dry mass with per unit phosphorus uptake.