水稻甬优12产量13.5t hm^(–2)以上超高产群体的磷素积累、分配与利用特征

Accumulation, Distribution, and Utilization Characteristics of Phosphorus in Yongyou 12 Yielding over 13.5 t ha^(–1)

为探明甬优12超高产群体的磷素吸收与积累特征,2013—2014年,对高产(10.5~12.0 t hm^(–2))、更高产(12.0~13.5 t hm^(–2))、超高产(>13.5 t hm^(–2))3个产量群体的磷素吸收与积累特征等进行了系统比较研究。结果表明:(1)生育期植株含磷量,不同产量水平群体间无显著差异;拔节期磷素吸收量呈高产群体>更高产群体>超高产群体;而抽穗期和成熟期磷素吸收量则呈超高产群体>更高产群体>高产群体。播种至拔节期的磷素积累量与产量呈极显著负相关;拔节至抽穗期、抽穗至成熟期的磷素积累量与产量呈极显著正相关。(2)甬优12超高产群体抽穗期茎鞘、叶片和穗部磷素积累量分别为41.4、8.5和8.9 kg hm^(–2),高于更高产群体(37.9、7.6和8.1 kg hm^(–2))和高产群体(32.3、6.8和7.0 kg hm^(–2))。抽穗期植株叶片、茎鞘和穗部磷素积累量与产量呈极显著正相关;甬优12超高产群体成熟期茎鞘、叶片和穗部磷素积累量分别为14.5、4.4和62.3 kg hm^(–2),高于更高产群体(13.6、3.3和55.9 kg hm^(–2))和高产群体(11.2、2.7和48.7 kg hm^(–2))。成熟期植株叶片、茎鞘和穗部磷素积累量与实产呈极显著正相关。此外,花后茎鞘磷素转运量亦与产量呈极显著正相关。(3)两年中,甬优12超高产群体磷素籽粒生产率(kg grain kg^(–1))和偏生产力(kg kg^(–1))分别为171.5、92.7,低于更高产(173.2、99.6)和高产群体(173.5、100.4);超高产群体磷收获指数为0.768,显著高于更高产(0.761)和高产(0.758)群体。与对照相比,甬优12超高产群体磷素吸收具有拔节前较低、拔节至抽穗期和抽穗至成熟期高的特点。播种至拔节期磷素积累量与产量呈极显著负相关;拔节至抽穗期、抽穗至成熟期磷素积累量与产量呈极显著正相关。甬优12超高产群体磷素利用效率较低,在其超高产栽培管理中应重视磷素的高效利用。在本研究基础上探讨了提高甬优12超高产群体磷素利用效率的措施。

In order to determine the absorption and accumulation of phosphorus（P） in super high yielding rice population of Yongyou 12, the field experiments were conducted with these populations of high yield（HY, 10.5–12.0 t ha^（–1））, higher yield（HRY, 12.0–13.5 t ha^（–1））, and super high yield（SHY,〉 13.5 t ha^（–1）） in 2013 and 2014. Results indicated that there was no significant difference in P content of plant at each growth stage among three yield groups. HY showed the highest P plant uptake while SHY the lowest at jointing among three yield groups. Opposite trends were observed at heading and maturity stages. There existed a significant（P 〈0.01） and negative correlation of the grain yield with P accumulation from sowing to jointing, while significant（P〈0.01） and positive correlations of grain yield with P accumulation from jointing to heading, and from heading to maturity. P accumulation in the stem and sheath, leaf, and panicle at heading was 41.4, 8.5, and 8.9 kg ha^（–1）, respectively for SHY, higher than those for HRY（37.9, 7.6, 8.1 kg ha^（–1）） and HY（32.3, 6.8, 7.0 kg ha^（–1））. There existed significant（P〈0.01） and positive correlations of grain yield with P accumulation in stem and sheath, leaf, and panicle at heading. P accumulation of SHY in stem and sheath, leaf, and panicle at maturity was 14.5, 4.4, 62.3 kg ha^（–1）, respectively, higher than those of HRY（13.6, 3.3, 55.9 kg ha^（–1）） and HY（11.2, 2.7, 48.7 kg ha^（–1））. There existed significant and positive linear correlation of grain yield with P accumulation in the stem and sheath, leaf, and panicle at maturity and with P translocation from stem and sheath to grain after heading. When values were averaged across two years, internal nutrient efficiency（kg grain kg^（–1）） and partial factor productivity（kg kg^（–1）） of SHY were 171.5 and 92.7, respectively, less than those of HRY（173.2, 99.6） and HY（173.5, 100.4）. Harvest index of P of SHY was 0.768, significantly higher than that of HRY（0.761） and HY（0.758）. SHY showed lower P accumulation before jointing, while higher P accumulation from jointing to heading, and from heading to maturity, when compared with check. There existed significant（P〈0.01） and negative correlation of grain yield with P accumulation from sowing to jointing, while significant（P〈0.01） and positive correlations of grain yield with P accumulation from jointing to heading, and heading to maturity. Relatively low P use efficiency was observed in SHY, a great attention should be paid to improving P use efficiency. Finally, methods to improve P use efficiency of SHY for Yongyou 12 were discussed.