氮肥运筹对双季晚稻产量及光合特性的影响

Effects of Nitrogen Application on Yield and Photosynthetic Characteristics of Double Cropping Late Rice

为明确湖南双季稻区"早蓄晚灌"节水轻简栽培条件下水稻生产适宜的氮肥施用模式,通过比较分析了"早蓄晚灌"节水轻简栽培条件下7种不同氮肥配比模式对晚稻产量及光合特性的影响。结果表明:氮肥配比为分蘖期∶孕穗期∶抽穗期=4∶3∶3时玉针香产量达到最高,为7 930 kg/hm2,较施氮处理高3.12%~15.94%,较不施氮处理高44.44%;氮肥配比为分蘖期∶孕穗期∶抽穗期=5∶3∶2时丰源优299产量最高,为7 980 kg/hm2,较施氮处理高2.57%~9.47%,较不施氮处理高40.74%。不同氮肥配比模式对水稻净光合速率在主要生育期内呈现出逐渐降低的趋势,且分蘖盛期-孕穗期降低趋势最大,玉针香降低幅度为29.92%~45.38%,丰源优299降低幅度为28.62%~36.51%;而孕穗期-乳熟期降低幅度玉针香为5.01%~17.47%,丰源优299为1.28%~13.28%。玉针香呈现不同处理对水稻的净光合速率在各个生育期有各自的特征,丰源优299在生育前期以处理A(一次性施复合肥作为基肥施入)最高,孕穗期-乳熟期以处理E(分蘖期∶孕穗期∶抽穗期=4∶3∶3)最佳。蒸腾速率表现随氮肥后移比例的增加,玉针香和丰源优299在水稻主要生育期内呈现逐步降低的趋势,在水稻分蘖盛期2个品种均以不施氮处理最佳,孕穗期、抽穗期和乳熟期均以处理C(分蘖期∶孕穗期∶抽穗期=6∶3∶1)施肥比例最佳。因此,合理的施氮比例能够有效地提高光合利用率,进而提高水稻生产效益。

To be explicit about Hunan double cropping ＂early storage late irrigation ＂water saving light and simple cultivation conditions suitable for rice production of nitrogen application pattern,the ＂early storage late irrigation ＂effects of 7 different nitrogen ratio models of water saving light and simple cultivation conditions on photosynthetic characteristics and yield of late rice were analyzed. The results showed that the maximum of Yuzhenxiang was showed in the nitrogen application ratio of tillering stage ∶ booting stage ∶ heading stage as 4 ∶ 3 ∶ 3 with 7 930 kg/ha ,higher 3.12%-15.94% than nitrogen treatment,higher 44.44% than without nitrogen treatment;Fengyuanyou 299 in the nitrogen application ratio of tillering stage ∶ booting stage ∶ heading stage as 5 ∶ 3 ∶ 2 with record of 7 980 kg/ha,compared with high nitrogen 2.57%-9.47%,compared with the treatment without nitrogen application 40.74% . Different nitrogen ratio on net photosynthetic rate of rice decreased gradually in the growth period and the trend of reducing the tillering stage to the booting stage was the biggest,Yuzhenxiang decreased to 29.92%- 45.38% ,Fengyuanyou 299 decreased to 28.62%-36.51%;and from booting stage to milk stage to reduce the amplitude of Yuzhenxiang 5.01%-17.47% and Fengyuanyou 299 1.28%-13.28%.Yuzhenxiang showed a net of light of different treatments on rice photosynthesis had their own characteristics in each growth period,Fengyuanyou 299 at early stage in the treatment of A（one-time application of compound fertilizer as basic fertilizer） highest. The best treatment of E（tillering stage ∶ booting stage ∶ heading stage =4 ∶ 3 ∶ 3）at booting stage-milk ripening period. The rate of transpiration increased with the proportion of nitrogen transfer Yuzhenxiang and Fengyuanyou 299 in the growth stage of rice had gradually decreased in the main growth period of rice,two varieties without nitrogen fertilizer,booting,heading and milk ripening stage were dealt with C（tillering stage ∶ booting stage ∶ heading stage= 6 ∶ 3 ∶ 1） optimum fertilization ratio. Therefore,the reasonable ratio of nitrogen application can effectively improve the photosynthetic utilization and improve the efficiency of rice production.