施氮量对籼粳杂交稻甬优1540产量和氮肥利用效率的影响及其机制  

Effects of nitrogen fertilizer rates on grain yield and nitrogen use efficiency of japonica-indica hybrid rice cultivar Yongyou 1540 and its physiological bases

作　　者：徐冉 陈松[1] 徐春梅[1] 刘元辉 章秀福[1] 王丹英[1] 褚光[1] XU Ran;CHEN Song;XU Chun-Mei;LIU Yuan-Hui;ZHANG Xiu-Fu;WANG Dan-Ying;CHU Guang(State Key Laboratory of Rice Biology/China National Rice Research Institute,Hangzhou 311400,Zhejiang,China)

机构地区：[1]中国水稻研究所/水稻生物学国家重点实验室,浙江杭州311400

出　　处：《作物学报》2023年第6期1630-1642,共13页Acta Agronomica Sinica

基　　金：浙江省重点研发计划项目(2021C02023,2022C02034);国家自然科学基金项目(32101825);财政部和农业农村部国家现代农业产业技术体系建设专项(水稻,CARS-01)资助

摘　　要：旨在探讨施氮量对籼粳杂交稻甬优1540产量和氮肥利用效率的影响及其相关生理基础。本研究以浙江省大面积推广应用的籼粳杂交稻品种甬优1540为材料,设置4个施氮量,即全生育期不施用氮肥(N0)、全生育期施用纯氮80 kg hm^(-2)(N1)、160 kg hm^(-2)(N2)以及240 kg hm^(-2)(N3)。研究结果表明,(1)施氮量对水稻产量与氮肥利用效率影响显著。在0~160 kg hm^(-2)范围内,水稻产量随施氮量的增加而增加,产量的增加主要得益于总颖花量的增加;超过此范围产量则不再增加,主要是由于结实率降低,且氮收获指数与氮肥利用效率(氮肥农学利用率、氮肥吸收利用率、氮肥偏生产力以及产谷利用率)也显著降低。(2)施氮量对水稻地上部生长发育影响显著。在0~240 kg hm^(-2)范围内,随着施氮量的增加,拔节期、齐穗期以及成熟期水稻地上部干物重显著增加,但收获指数则显著降低;在0~160 kg hm^(-2)范围内,灌浆中、后期水稻剑叶净光合速率、剑叶中Z+ZR含量以及籽粒中蔗糖-淀粉代谢途径关键酶活性随施氮量的增加而增加,超过此范围则不再增加,甚至会有所降低。(3)施氮量对水稻根系形态生理特征影响显著。在0~160 kg hm^(-2)范围内,拔节期、齐穗期以及成熟期水稻根干重、0~10 cm土层根干重、10~20 cm土层根干重、总根长、根长密度、比根长以及灌浆中、后期水稻根系氧化力、根系与根系伤流液中Z+ZR浓度水平等根系形态与生理指标均随施氮量的增加而增加,但进一步将施氮量提高至240 kg hm^(-2)时,上述指标中仅根干重、0~10 cm土层根干重、总根长以及根长密度有所增加。(4)相关分析表明,灌浆期水稻根系氧化力、根系中Z+ZR含量以及根系伤流液中Z+ZR浓度与剑叶净光合速率、剑叶中Z+ZR含量以及籽粒中蔗糖-淀粉代谢途径关键酶活性呈极显著正相关关系。以上结果表明,适宜的施氮量可以优化甬优1540�The objective of this study is to understand how nitrogen(N)application rates affected on grain yield and N use efficiency(NUE)of japonica-indica hybrid rice cultivar Yongyou-1540 and its physiological bases.In the present study,a japonica-indica hybrid rice cultivar Yongyou 1540,which was widely planted in Zhejiang province was field grown in 2020 and 2021,and four N application rates[0 kg hm^(-2)(N0),80 kg hm^(-2)(N1),160 kg hm^(-2)(N2),and 240 kg hm^(-2)(N3)]were applied during rice growing season.The results indicated that,(1)N application rate had significant effects on grain yield and NUE of rice.Grain yield was significantly increased with the increase of N application rate from 0 kg hm^(-2)to 160 kg hm^(-2),and the increase in grain yield was mainly attributed to the increase in total spikelets per unit area.However,there were no significantly difference in grain yield between N2 and N3 treatments,which was mainly due to the reduce in grain filling percentage in N3 treatment.When compared with N2 treatment,N3 treatment significantly reduced N harvest index and NUE,including agronomic N use efficiency(AEN),N recovery efficiency(REN),N partial factor productivity(PFPN),and internal N use efficiency(IEN).(2)N application rate had significant effects on shoot growth and development.Shoot dry weight was significantly increased at jointing,heading,and maturity stages and harvest index was significantly decreased with the increase of N application rate from 0 kg hm^(-2)to 240 kg hm^(-2).The net photosynthetic rate of flag leaf,the concentration of zeatin plus zeatin riboside(Z+ZR)in flag leaves,and the activities of key enzymes involved in sucrose-to-starch conversion in grains were significantly increased with the increase of N application rate from 0 kg hm^(-2)to 160 kg hm^(-2),however,N3 treatment could not increase or even reduce the above indicators compared with N2 treatment.(3)N application rate had significant effects on rice root morphological and physiological traits.Root dry weight,root dry weight in

关 键 词：籼粳杂交稻 施氮量 产量 氮肥利用率 根系形态生理 

分 类 号：S511[农业科学—作物学]