氮素对超级早稻冠层叶片光合生理和物质生产的影响

Effects of Nitrogen on Photosynthetic Physiology of Canopy Leaves and Matter Production of Early Super Rice

以超级稻中早39和中嘉早17为材料,系统比较了施氮肥与不施氮肥2个处理下冠层上三叶光合特性、产量、干物质积累和氮素吸收利用,旨在探明氮素对超级早稻冠层叶片光合生理和物质生产的影响。结果表明,施氮处理能够不同程度增加超级早稻幼穗分化5期冠层上三叶(完全叶)的叶面积、叶片厚度和SPAD值,且施氮能够不同程度减缓叶片衰老,与不施氮处理相比,成熟期中早39和中嘉早17倒1叶的饱和净光合速率分别显著增加了35.1%、28.8%,有利于保持较强的光合作用。同时施氮处理能够提高2个品种的干物质积累量和氮素吸收利用效率,显著增加有效穗数、每穗总粒数和结实率,其中中早39分别增加了34.5%、19.0%和8.5%,中嘉早17分别增加了44.0%、30.2%和7.3%。与不施氮处理相比,中早39和中嘉早17施氮处理分别增产57.4%、91.9%。综上,施氮处理能够显著增加超级早稻冠层叶片的光合能力,同时显著增加有效穗数和每穗总粒数,进而提升了产量。

Using Zhongzao 39 and Zhongjiazao 17 as materials,the photosynthetic characteristics of upper three leaves in canopy,yield,dry matter accumulation and nitrogen uptake and utilization of early super rice under two treatments of nitrogen fertilizer application and no application of nitrogen fertilizer were systematically compared to investigate the effects of nitrogen on photosynthetic physiology of canopy leaves and matter production of early super rice.The results showed that nitrogen application could increase the leaf area,leaf thickness and SPAD value of the upper three leaves(complete leaves)in canopy at the 5th stage of young panicle differentiation of early super rice to varying degrees,and nitrogen application could slow down leaf senescence to varying degrees.The saturated net photosynthetic rate of Zhongzao 39 and Zhongjiazao 17 was significantly increased by 35.1%and 28.8%,respectively,which was conducive to maintaining a strong photosynthesis.The dry matter accumulation and nitrogen uptake and use efficiency of the two varieties were increased significantly by nitrogen application,and the number of effective panicles,the number of spikelets per panicle and seed setting rate were increased by 34.5%,19.0%and 8.5%in Zhongzao 39 and 44.0%,30.2%and 7.3%in Zhongjiazao 17,respectively.Compared with no nitrogen application,the treatment of nitrogen application increased the yield of Zhongzao 39 and Zhongjiazao 17 by 57.4%and 91.9%,respectively.In conclusion,nitrogen application can significantly increase the photosynthetic capacity of canopy leaves,and significantly increase the number of effective panicles and spikelets per panicle,thus improving the yield of early super rice.