Padhan Birendra K, Sathee Lekshmy, Kumar Santosh, Chinnusamy Viswanathan, Kumar Arvind
Division of Plant Physiology, ICAR-Indian Agricultural Research Institute, New Delhi, India.
Division of Crop Research, Indian Council of Agricultural Research (ICAR) Research Complex for Eastern Region, Patna, Bihar, India.
Front Plant Sci. 2023 Mar 3;14:1093581. doi: 10.3389/fpls.2023.1093581. eCollection 2023.
Nitrogen (N) is an important macronutrient needed for grain yield, grain N and grain protein content in rice. Grain yield and quality are significantly determined by N availability. In this study, to understand the mechanisms associated with reproductive stage N remobilization and N partitioning to grain 2 years of field experiments were conducted with 30 diverse rice genotypes during 2019-Kharif and 2020-Kharif seasons. The experiments were conducted with two different N treatments; N deficient (N0-no external N application, available soil N; 2019-234.15 kgha-1, 2020-225.79 kgha-1) and N sufficient (N120-120 kgha-1 external N application, available soil N; 2019-363.77 kgha-1, 2020-367.95 kgha-1). N application increased the NDVI value, biomass accumulation, grain yield, harvest index and grain N accumulation. Post-anthesis N uptake and N remobilization from vegetative tissues to grain are critical for grain yield and N harvest index. Rice genotypes, Kalinga-1, BAM-4234, IR-8384-B-B102-3, Sahbhagi Dhan, BVD-109 and Nerica-L-42 showed a higher rate of N remobilization under N sufficient conditions. But, under N deficiency, rice genotypes-83929-B-B-291-3-1-1, BVD-109, IR-8384-B-B102-3 and BAM-4234 performed well showing higher N remobilization efficiency. The total amount of N remobilization was recorded to be high in the N120 treatment. The harvest index was higher in N120 during both the cropping seasons. RANBIR BASMATI, BAM-832, APO, BAM-247, IR-64, Vandana, and Nerica-L-44 were more efficient in N grain production efficiency under N deficient conditions. From this study, it is evident that higher grain N accumulation is not always associated with higher yield. IR-83929-B-B-291-3-1-1, Kalinga-1, APO, Pusa Basmati-1, and Nerica-L-44 performed well for different N use efficiency component traits under both N deficient (N0) and N sufficient (N120) conditions. Identifying genotypes/donors for N use efficiency-component traits is crucial in improving the fertilizer N recovery rate and site specific N management.
氮（N）是水稻籽粒产量、籽粒氮含量和籽粒蛋白质含量所需的重要大量营养素。籽粒产量和品质显著取决于氮的有效性。在本研究中，为了解与生殖阶段氮素再转运及氮素向籽粒分配相关的机制，于2019年雨季和2020年雨季对30个不同水稻基因型进行了为期两年的田间试验。试验采用两种不同的氮处理；缺氮（N0 - 不施外源氮，利用土壤有效氮；2019年 - 234.15千克/公顷，2020年 - 225.79千克/公顷）和施氮充足（N120 - 施120千克/公顷外源氮，利用土壤有效氮；2019年 - 363.77千克/公顷，2020年 - 367.95千克/公顷）。施氮提高了归一化植被指数值、生物量积累、籽粒产量、收获指数和籽粒氮积累量。花后氮素吸收以及从营养组织向籽粒的氮素再转运对籽粒产量和氮收获指数至关重要。水稻基因型Kalinga - 1、BAM - 4234、IR - 8384 - B - B102 - 3、Sahbhagi Dhan、BVD - 109和Nerica - L - 42在施氮充足条件下表现出较高的氮再转运率。但是，在缺氮条件下，水稻基因型83929 - B - B - 291 - 3 - 1 - 1、BVD - 109、IR - 8384 - B - B102 - 3和BAM - 4234表现良好，氮再转运效率较高。在N120处理中记录到氮再转运总量较高。在两个种植季节中，N120处理的收获指数都较高。RANBIR BASMATI、BAM - 832、APO、BAM - 247、IR - 64、Vandana和Nerica - L - 44在缺氮条件下氮素籽粒生产效率更高。从本研究可以明显看出，较高的籽粒氮积累并不总是与较高的产量相关。IR - 83929 - B - B - 291 - 3 - 1 - 1、Kalinga - 1、APO、Pusa Basmati - 1和Nerica - L - 44在缺氮（N0）和施氮充足（N120）条件下，对于不同的氮利用效率组成性状都表现良好。鉴定氮利用效率组成性状的基因型/供体对于提高肥料氮回收率和特定地点的氮肥管理至关重要。
