Characteristics of Nitrogen Absorption and Utilization of an indica-japonica Hybrid Rice, Yongyou 2640

doi:10.16819/j.1001-7216.2022.210310

Abstract

Abstract:

【Objective】It is very important to elucidate the characteristics and mechanism of nitrogen (N) uptake and utilization in indica-japonica hybrid rice. 【Method】 An indica-japonica hybrid rice combination Yongyou 2640 and two inbred rice cultivars of Lianjing 7 (japonica) and Yangdao 6 (indica) were field-grown, and six N application rates (0, 100, 200, 300, 400, 500 kg/hm ²) and a ¹⁵N tracer micro-area experiment were designed. 【Result】 With increasing N rates (from 0 to 400 kg/hm ²), the grain yield of Yongyou 2640 increased, and that of Lianjing 7 and Yangdao 6 increased first and then decreased, and the highest grain yield was found at the N rate of 300 kg/hm ². At the same N rate, grain yield of Yongyou 2640 was higher than that of Lianjing 7 or Yangdao 6. A higher grain yield of Yongyou 2640 was mainly attributed to the higher above-ground dry matter and total amount of spikelets. The accumulation of ¹⁵N in grains increased, whereas the distribution ratio of ¹⁵N in grain decreased gradually correspondingly with increasing N application rates. A high N rate caused a drop in N harvest index. The distribution ratio of ¹⁵N in grains of Yongyou 2640 was higher than that of Lianjing 7 or Yangdao 6, while lower than that of the two control cultivars in the stems, sheaths and leaves of Yongyou 2640. The activities of nitrate reductase, glutamine syntetase and glutamate synthase in leaves of the three rice cultivars were enhanced with increasing N rates. At the same nitrogen rate, the activities of above enzymes in Yongyou 2640 were significantly higher than those of Lianjing 7 or Yangdao 6. 【Conclusion】 The indica-japonica hybrid rice Yongyou 2640 is characterized by stronger nitrogen uptake and utilization capacity as compared with inbred japonica rice cultivar (Lianjing 7) or indica rice cultivar (Yangdao 6).

Key words: rice, ¹⁵N tracer technique, nitrogen rate, uptake and distribution

摘要：

【目的】探明籼粳杂交稻甬优2640的氮素吸收利用特点。【方法】籼粳杂交稻甬优2640、常规粳稻连粳7号和常规籼稻扬稻6号种植于大田,设置6种施氮量处理(0、100、200、300、400、500 kg/hm ²)和 ¹⁵N示踪微区试验。【结果】在0~400 N kg/hm ²范围内,甬优2640的稻谷产量随施氮量的增加而提高;连粳7号和扬稻6号的产量则是先增加后降低,在施氮量300 kg/hm ²时产量最高;相同施氮量下,甬优2640的产量均高于连粳7号和扬稻6号。甬优2640产量较高,这得益于地上部较高的干物质量和库容量(总颖花量)。适量增施氮肥提高了籽粒中 ¹⁵N积累量,但其在籽粒中的分配比例却随施氮量的增加而降低。甬优2640穗中的 ¹⁵N分配比例高于连粳7号和扬稻6号。高施氮量降低水稻氮收获指数。增施氮肥明显提高3个水稻品种穗分化期、抽穗期和灌浆中期叶片的硝酸还原酶、谷氨酰胺合成酶和谷氨酸合酶活性;相同施氮量下,甬优2640的各种酶活性显著高于连粳7号和扬稻6号。【结论】籼粳杂交稻甬优2640较常规水稻品种具有更强的氮素吸收与利用能力。

关键词: 水稻, ¹⁵N示踪技术, 施氮量, 吸收分配

YUAN Rui, ZHOU Qun, WANG Zhiqin, ZHANG Hao, GU Junfei, LIU Lijun, ZHANG Weiyang, YANG Jianchang. Characteristics of Nitrogen Absorption and Utilization of an indica-japonica Hybrid Rice, Yongyou 2640[J]. Chinese Journal OF Rice Science, 2022, 36(1): 77-86.

袁锐, 周群, 王志琴, 张耗, 顾骏飞, 刘立军, 张伟杨, 杨建昌. 籼粳杂交稻甬优2640氮素吸收利用特点[J]. 中国水稻科学, 2022, 36(1): 77-86.

Figures/Tables 7

References 35

[1]	FAOSTAT. FAO Statistical Databases, Food and Agriculture Organization (FAO) of the United Nations[DB/OL]. Rome, 2019. [2021-03-20]. http://www.fao.org.
[2]	Zhang H, Yu C, Kong X S, Hou D P, Gu J F, Liu L J, Wang Z Q, Yang J C. Progressive integrative crop managements increase grain yield, nitrogen use efficiency and irrigation water productivity in rice[J]. Field Crops Research, 2018,215:1-11.
[3]	Peng S B, Tang Q Y, Zou Y B. Current status and challenges of rice production in China[J]. Plant Production Science, 2009,12:3-8.
[4]	国家统计局. 国家统计局关于2020年粮食产量数据的公告[EB/OL]. 2020. http://www.stats.gov.cn/.
	National Bureau of Statistics. Announcement of the National Bureau of Statistics on grain production data in 2020[EB/OL]. 2020. http://www.stats.gov.cn.
[5]	褚光, 展明飞, 朱宽宇, 王志琴, 杨建昌. 干湿交替灌溉对水稻产量与水分利用效率的影响[J]. 作物学报, 2016,42(7):1026-1036.
	Chu G, Zhan M F, Zhu K Y, Wang Z Q, Yang J C. Effects of alternate wetting and drying irrigation on yield and water use efficiency of rice[J]. Acta Agronomica Sinica, 2016,42(7):1026-1036. (in Chinese with English abstract)
[6]	Wang Z Q, Gu D J, Beebout S S, Zhang H, Liu L J, Yang J C, Zhang J H. Effect of irrigation regime on grain yield, water productivity, and methane emissions in dry direct-seeded rice grown in raised beds with wheat straw incorporation[J]. The Crop Journal, 2018,6(5):495-508.
[7]	朱宽宇, 展明飞, 陈静, 王志琴, 杨建昌, 赵步洪. 不同氮肥水平下结实期灌溉方式对水稻弱势粒灌浆及产量的影响[J]. 中国水稻科学, 2018,32(2):155-168.
	Zhu K Y, Zhan M F, Chen J, Wang Z Q, Yang J C, Zhao B H. Effects of irrigation regimes during grain filling under different nitrogen rates on inferior spikelets grain-filling and grain yield of rice[J]. Chinese Journal of Rice Science, 2018,32(2):155-168. (in Chinese with English abstract)
[8]	Zhang G Q. Prospects of utilization of inter-subspecific heterosis between indica and japonica rice[J]. Journal of Integrative Agriculture, 2020,19(1):1-10.
[9]	韦还和, 孟天瑶, 李超, 张洪程, 戴其根, 马荣荣, 王晓燕, 杨筠文. 水稻甬优12产量13.5 t ha ^-1以上超高产群体的磷素积累、分配与利用特征 [J]. 作物学报, 2016,42(6):886-897.
	Wei H H, Meng T Y, Li C, Zhang H C, Dai Q G, Ma R R, Wang X Y, Yang J W. Accumulation, distribution, and utilization characteristics of phosphorus in Yongyou12 yielding over 13.5 t ha ^-1 [J]. Acta Agronomica Sinica, 2016,42(6):886-897. (in Chinese with English abstract)
[10]	Wei H H, Meng T Y, Li C, Xu K, Huo Z Y, Wei H Y, Guo B W, Zhang H C, Dai Q G. Comparisons of grain yield and nutrient accumulation and translocation in high-yielding japonica/indica hybrids, indica hybrids, and japonica conventional varieties[J]. Field Crops Research, 2017,204:101-109.
[11]	Chu G, Chen S, Xu C M, Wang D Y, Zhang X F. Agronomic and physiological performance of indica/japonica hybrid rice cultivar under low nitrogen conditions[J]. Field Crops Research, 2019,243:107625.
[12]	Zhang Z J, Chu G, Liu L J, Wang Z Q, Wang X M, Zhang H, Yang J C, Zhang J H. Mid-season nitrogen application strategies for rice varieties differing in panicle size[J]. Field Crops Research, 2013,150:9-18.
[13]	魏海燕, 张洪程, 戴其根, 霍中洋, 许柯, 杭杰, 马群, 张胜飞, 张庆, 刘艳阳. 不同水稻氮利用效率基因型的物质生产与积累特性[J]. 作物学报, 2007(11):1802-1809.
	Wei H Y, Zhang H C, Dai Q G, Huo Z Y, Xu K, Hang J, Ma Q, Zhang S F, Zhang Q, Liu Y Y. Characteristics of matter production and accumulation in rice genotypes with different N use efficiency[J]. Acta Agronomica Sinica, 2007(11):1802-1809. (in Chinese with English abstract)
[14]	Zhu K Y, Zhou Q, Shen Y, Yan J Q, Xu Y J, Wang Z Q, Yang J C. Agronomic and physiological performance of an indica-japonica rice variety with a high yield and high nitrogen use efficiency[J]. Crop Science, 2020,60(3), 1556-1568.
[15]	黄见良, 邹应斌, 彭少兵, Buresh R J. 水稻对氮素的吸收、分配及其在组织中的挥发损失[J]. 植物营养与肥料学报, 2004(6):579-583.
	Huang J L, Zou Y B, Peng S B, Buresh R J. Nitrogen uptake, distribution by rice and its losses from plant tissues[J]. Plant Nutrition and Fertilizer Science, 2004(6):579-583. (in Chinese with English abstract)
[16]	Wang D Y, Xu C M, Yan J X, Zhang X G, Chen S, Chauhan B S, Wang L, Zhang X F. ¹⁵N tracer-based analysis of genotypic differences in the uptake and partitioning of N applied at different growth stages in transplanted rice [J]. Field Crops Research, 2017,211, 27-36.
[17]	Wang J, Fu P H, Wang F, Fahad S, Mohapatra P K, Chen Y T, Zhang C D, Peng S B, Cui K H, Nie L X, Huang J L. Optimizing nitrogen management to balance rice yield and environmental risk in the Yangtze River’s middle reaches[J]. Environmental Science and Pollution Research, 2019,26(5):4901-4912.
[18]	李合生. 植物生理生化实验原理和技术. 北京: 高等教育出版社, 2000: 125-127.
	Li H S. Principles and Techniques of Plant Physiological and Biochemical Experiments. Beijing: Higher Education Press, 2000: 125-127.
[19]	李俊峰, 杨建昌. 水分与氮素及其互作对水稻产量和水肥利用效率的影响研究进展[J]. 中国水稻科学, 2017,31(3):327-334.
	Li J F, Yang J C. Research advances in the effects of water, nitrogen and their interaction on the yield, water and nitrogen use efficiencies of rice[J]. Chinese Journal of Rice Science, 2017,31(3):327-334. (in Chinese with English abstract)
[20]	褚光, 陈婷婷, 陈松, 徐春梅, 王丹英, 章秀福. 灌溉模式与施氮量交互作用对水稻产量以及水、氮利用效率的影响[J]. 中国水稻科学, 2017,31(5):513-523.
	Chu G, Chen T T, Chen S, Xu C M, Wang D Y, Zhang X F. Effects of interaction between irrigation regimes and nitrogen rates on rice yield and water and nitrogen use efficiencies[J]. Chinese Journal of Rice Science, 2017,31(5):513-523. (in Chinese with English abstract)
[21]	Zhang W Y, Zhu K Y, Wang Z Q, Zhang H, Gu J F, Liu L J, Yang J C, Zhang J H. Brassinosteroids function in spikelet differentiation and degeneration in rice[J]. Journal of Integrative Plant Biology, 2019,61(8):943-963.
[22]	姜元华, 张洪程, 赵可, 许俊伟, 韦还和, 龙厚元, 王文婷, 戴其根, 霍中洋, 许轲, 魏海燕, 郭保卫. 长江下游地区不同类型水稻品种产量及其构成因素特征的研究[J]. 中国水稻科学, 2014,28(6):621-631.
	Jiang Y H, Zhang H C, Zhao K, Xu J W, Wei H H, Long H Y, Wang W T, Dai Q G, Huo Z Y, Xu K, Wei H Y, Guo B W. Different in yield and its components characteristics of different type rice cultivars in the lower reaches of yangtze river[J]. Chinese Journal of Rice Science, 2014,28(6):621-631. (in Chinese with English abstract)
[23]	凌启鸿, 张洪程, 蔡建中, 苏祖芳, 凌励. 水稻高产群体质量及其优化控制探讨[J]. 中国农业科学, 1993(6):1-11.
	Ling Q H, Zhang H C, Cai J Z, Su Z F, Ling L. Investigation on the population quality of high yield and its optimizing control programme in rice[J]. Scientia Agricultura Sinica, 1993(6):1-11. (in Chinese with English abstract)
[24]	Evans L T, Fischer R A . Yield potential: Its definition, measurement, and significance[J]. Crop Science, 1999,39(6):1544-1551.
[25]	Laza M R, Peng S B, Akita S G, Saka H S. Contribution of Biomass Partitioning and Translocation to Grain Yield under Sub-Optimum Growing Conditions in Irrigated Rice[J]. Plant Production Science, 2015,6(1):28-35.
[26]	Peng S B, Cassman K G, Virmani S S, Sheehy J, Khush G S. Yield potential trends of tropical rice since the release of IR8 and the challenge of increasing rice yield potential[J]. Crop Science, 1999,39(6):1552-1559.
[27]	Zhang Y B, Tang Q Y, Zou Y B, Li J Q, Qin J Q, Yang S H, Chen L J, Xia B, Peng S B. Yield potential and radiation use efficiency of “super” hybrid rice grown under subtropical conditions[J]. Field Crops Research, 2009,114(1):91-98.
[28]	程建峰, 戴廷波, 曹卫星, 姜东, 潘晓云. 不同氮收获指数水稻基因型的氮代谢特征[J]. 作物学报, 2007,33(3):497-502.
	Cheng J F, Dai T B, Cao W X, Jiang D, Pan X Y. Nitrogen metabolic characteristics in rice genotypes with diffrernt nitrogen harvest index[J]. Acta Agronomica Sinica, 2007,33(3):497-502. (in Chinese with English abstract)
[29]	Wang Z Q, Zhang W Y, Beebout S S, Zhang H, Liu L J, Yang J C, Zhang J H. Grain yield, water and nitrogen use efficiencies of rice as influenced by irrigation regimes and their interaction with nitrogen rates[J]. Field Crops Research, 2016,193:54-69.
[30]	Ju C X, Buresh R J, Wang Z Q, Zhang H, Liu L J, Yang J C, Zhang J H. Root and shoot traits for rice varieties with higher grain yield and higher nitrogen use efficiency at lower nitrogen rates application[J]. Field Crops Research, 2015,175:47-55.
[31]	Wang J L, Fu Z S, Chen G F, Zou G Y, Song X F, Liu F X. Runoff nitrogen (N) losses and related metabolism enzyme activities in paddy field under different nitrogen fertilizer levels[J]. Environmental Science and Pollution Research, 2018,25(27):27583-27593.
[32]	叶利庭, 吕华军, 宋文静, 图尔迪, 沈其荣, 张亚丽. 不同氮效率水稻生育后期氮代谢酶活性的变化特征[J]. 土壤学报, 2011,48(1):132-140.
	Ye L T, Lyu H J, Song W J, Tu E D, Shen Q R, Zhang Y L. Changes of nitrogen metabolism enzyme activities in late growth stage of rice with different nitrogen efficiency[J]. Acta Pedologica Sinica, 2011,48(1):132-140. (in Chinese with English abstract)
[33]	孙永健, 孙园园, 李旭毅, 郭翔, 马均. 水氮互作下水稻氮代谢关键酶活性与氮素利用的关系[J]. 作物学报, 2009,35(11):2055-2063.
	Sun Y J, Sun Y Y, Li X Y, Guo X, Ma J. Relationship of activities of key enzymes involved in nitrogen metabolism with nitrogen utilization in rice under water-nitrogen interaction[J]. Acta Agronomica Sinica, 2009,35(11):2055-2063. (in Chinese with English abstract)
[34]	杨建昌. 水稻弱势粒灌浆机理与调控途径[J]. 作物学报, 2010,36(12):2011-2019.
	Yang J C. Mechanism and regulation in the filling of inferior spikelets of rice[J]. Acta Agronomica Sinica, 2010,36(12):2011-2019. (in Chinese with English abstract)
[35]	徐云姬, 许阳东, 李银银, 钱希旸, 王志琴, 杨建昌. 干湿交替灌溉对水稻花后同化物转运和籽粒灌浆的影响[J]. 作物学报, 2018,44(4):554-568.
	Xu Y J, Xu Y D, Li Y Y, Qian X Y, Wang Z Q, Yang J C. Effect of alternate wetting and drying irrigation on post-anjournal remobilization of assimilates and grain filling of rice[J]. Acta Agronomica Sinica, 2018,44(4):554-568. (in Chinese with English abstract)

品种 Variety	施氮量 N rate /(kg·hm^-2)	穗数 Number of panicles /(×10⁴·hm^-2)	每穗粒数 Spikelets per panicle	总颖花量 Total spikelets /(×10⁶·hm^-2)	结实率 Seed setting rate/%	千粒重 1000-grain weight/g	产量 Yield/(t·hm^-2)	收获指数 Harvest index
甬优2640 Yongyou 2640	0	128 l	267 d	343 k	87.6 bc	25.4 e	7.62 h	0.500 b
甬优2640 Yongyou 2640	100	157 j	289 c	453 f	86.3 c	25.3 e	9.81 e	0.478 d
	200	180 i	301 b	579 c	85.7 cd	25.3 e	11.40 b	0.500 b
	300	195 g	340 a	654 b	82.7 e	24.9 f	12.90 a	0.510 a
	400	201 f	343 a	687 a	80.3 f	24.5 f	13.30 a	0.510 a
	500	205 e	337 a	690 a	78.2 g	24.3 f	13.00 a	0.490 c
连粳7号 Lianjing 7	0	222 d	120 k	266 m	91.0 a	27.4 c	6.45 i	0.493 c
连粳7号 Lianjing 7	100	261 c	132 j	344 k	90.6 a	27.3 c	8.32 g	0.481 d
	200	289 b	151 i	447 g	89.3 b	27.2 cd	10.10 d	0.501 b
	300	304 a	161 h	504 e	85.1 d	26.6 d	10.70 c	0.503 b
	400	305 a	162 h	511 d	82.1 e	26.3 d	10.30 cd	0.490 c
	500	302 a	160 h	499 e	80.6 f	26.1 d	9.64 e	0.462 f
扬稻6号 Yangdao 6	0	136 k	166 h	231 n	87.0 c	30.9 a	6.01 j	0.460 f
扬稻6号 Yangdao 6	100	160 j	180 g	295 l	85.9 cd	30.5 a	7.39 h	0.445 h
	200	177 i	195 f	362 k	84.8 d	30.1 ab	8.57 g	0.453 g
	300	191 h	203 e	425 h	83.5 de	29.8 b	9.41 ef	0.470 e
	400	195 g	198 f	418 i	82.3 e	29.7 b	9.16 f	0.442 h
	500	190 h	196 f	405 j	80.7 f	29.5 b	8.60 g	0.420 i

品种 Variety	施氮量 N rate /(kg·hm^-2)	穗数 Number of panicles /(×10⁴·hm^-2)	每穗粒数 Spikelets per panicle	总颖花量 Total spikelets /(×10⁶·hm^-2)	结实率 Seed setting rate/%	千粒重 1000-grain weight/g	产量 Yield/(t·hm^-2)	收获指数 Harvest index
甬优2640 Yongyou 2640	0	128 l	267 d	343 k	87.6 bc	25.4 e	7.62 h	0.500 b
甬优2640 Yongyou 2640	100	157 j	289 c	453 f	86.3 c	25.3 e	9.81 e	0.478 d
	200	180 i	301 b	579 c	85.7 cd	25.3 e	11.40 b	0.500 b
	300	195 g	340 a	654 b	82.7 e	24.9 f	12.90 a	0.510 a
	400	201 f	343 a	687 a	80.3 f	24.5 f	13.30 a	0.510 a
	500	205 e	337 a	690 a	78.2 g	24.3 f	13.00 a	0.490 c
连粳7号 Lianjing 7	0	222 d	120 k	266 m	91.0 a	27.4 c	6.45 i	0.493 c
连粳7号 Lianjing 7	100	261 c	132 j	344 k	90.6 a	27.3 c	8.32 g	0.481 d
	200	289 b	151 i	447 g	89.3 b	27.2 cd	10.10 d	0.501 b
	300	304 a	161 h	504 e	85.1 d	26.6 d	10.70 c	0.503 b
	400	305 a	162 h	511 d	82.1 e	26.3 d	10.30 cd	0.490 c
	500	302 a	160 h	499 e	80.6 f	26.1 d	9.64 e	0.462 f
扬稻6号 Yangdao 6	0	136 k	166 h	231 n	87.0 c	30.9 a	6.01 j	0.460 f
扬稻6号 Yangdao 6	100	160 j	180 g	295 l	85.9 cd	30.5 a	7.39 h	0.445 h
	200	177 i	195 f	362 k	84.8 d	30.1 ab	8.57 g	0.453 g
	300	191 h	203 e	425 h	83.5 de	29.8 b	9.41 ef	0.470 e
	400	195 g	198 f	418 i	82.3 e	29.7 b	9.16 f	0.442 h
	500	190 h	196 f	405 j	80.7 f	29.5 b	8.60 g	0.420 i

品种 Variety	施氮量 N rate /(kg·hm^-2)	吸氮量 N uptake (kg·hm^-2)	产谷利用率 IE /(kg·kg^-1)	氮肥偏生产力 NPFP /(kg·kg^-1)	氮肥生理利用率 NPE /(kg·kg^-1)	氮肥吸收利用率 NRE /%	氮肥农学利用率 NAE /(kg·kg^-1)
甬优2640	0	106 h	72.0 a
Yongyou 2640	100	151 f	63.5 b	96.0 a	43.7 b	45.8 a	20.0 a
	200	195 d	58.4 c	57.0 d	42.4 b	44.8 ab	19.0 b
	300	238 b	54.3 d	43.0 f	40.2 c	44.0 b	17.7 c
	400	255 a	52.1 e	33.3 h	38.1 d	37.4 d	14.3 d
	500	259 a	48.4 f	26.0 j	33.1 f	32.6 f	10.8 g
连粳7号 Lianjing 7	0	98 i	64.8 b
连粳7号 Lianjing 7	100	140 g	59.4 c	83.0 b	46.2 a	41.1 c	19.0 b
	200	179 e	56.4 cd	50.5 e	46.0 a	40.3 c	18.5 bc
	300	206 c	52.0 e	35.7 g	40.2 c	35.6 e	14.3 d
	400	209 c	49.4 f	25.8 j	35.5 e	27.5 g	9.8 h
	500	213 c	45.0 g	19.2 l	27.9 gh	22.9 h	6.4 j
扬稻6号 Yangdao 6	0	101 hi	59.3 c
扬稻6号 Yangdao 6	100	146 f	49.9 ef	73.0 c	28.8 g	45.2 ab	13.0 e
	200	188 d	45.1 g	42.5 f	28.7 g	43.6 b	12.5 e
	300	227 b	41.4 h	31.3 i	27.0 h	41.9 bc	11.3 f
	400	232 b	39.3 i	22.8 k	22.1 i	32.6 f	7.8 i
	500	235 b	36.6 j	17.2 m	17.6 j	26.8 g	5.2 k

品种 Variety	施氮量 N rate /(kg·hm^-2)	吸氮量 N uptake (kg·hm^-2)	产谷利用率 IE /(kg·kg^-1)	氮肥偏生产力 NPFP /(kg·kg^-1)	氮肥生理利用率 NPE /(kg·kg^-1)	氮肥吸收利用率 NRE /%	氮肥农学利用率 NAE /(kg·kg^-1)
甬优2640	0	106 h	72.0 a
Yongyou 2640	100	151 f	63.5 b	96.0 a	43.7 b	45.8 a	20.0 a
	200	195 d	58.4 c	57.0 d	42.4 b	44.8 ab	19.0 b
	300	238 b	54.3 d	43.0 f	40.2 c	44.0 b	17.7 c
	400	255 a	52.1 e	33.3 h	38.1 d	37.4 d	14.3 d
	500	259 a	48.4 f	26.0 j	33.1 f	32.6 f	10.8 g
连粳7号 Lianjing 7	0	98 i	64.8 b
连粳7号 Lianjing 7	100	140 g	59.4 c	83.0 b	46.2 a	41.1 c	19.0 b
	200	179 e	56.4 cd	50.5 e	46.0 a	40.3 c	18.5 bc
	300	206 c	52.0 e	35.7 g	40.2 c	35.6 e	14.3 d
	400	209 c	49.4 f	25.8 j	35.5 e	27.5 g	9.8 h
	500	213 c	45.0 g	19.2 l	27.9 gh	22.9 h	6.4 j
扬稻6号 Yangdao 6	0	101 hi	59.3 c
扬稻6号 Yangdao 6	100	146 f	49.9 ef	73.0 c	28.8 g	45.2 ab	13.0 e
	200	188 d	45.1 g	42.5 f	28.7 g	43.6 b	12.5 e
	300	227 b	41.4 h	31.3 i	27.0 h	41.9 bc	11.3 f
	400	232 b	39.3 i	22.8 k	22.1 i	32.6 f	7.8 i
	500	235 b	36.6 j	17.2 m	17.6 j	26.8 g	5.2 k

品种 Variety	施氮量 N rate /(kg·hm^-2)	¹⁵N累积量 ¹⁵N accumulation/(kg·hm^-2)			¹⁵N在植株中的分配率 ¹⁵N distribution in plant/%
品种 Variety	施氮量 N rate /(kg·hm^-2)	茎鞘 Stem and sheath	叶 Leaf	籽粒 Grain	茎鞘 Stem and sheath	叶 Leaf	籽粒 Grain
甬优2640 Yongyou 2640	100	6.0 o	2.4 m	22.3 k	19.5 o	7.8 k	72.6 a
甬优2640 Yongyou 2640	200	13.9 l	4.0 k	34.5 h	26.5 m	7.6 l	65.8 b
	300	22.9 i	4.6 i	52.4 c	28.7 l	5.8 n	65.6 b
	400	29.2 e	7.1 g	60.0 a	30.3 j	7.4 m	62.3 d
	500	36.3 c	9.8 d	60.5 a	34.1 d	9.2 f	56.8 i
连粳7号 Lianjing 7	100	6.6 n	3.1 l	18.0 l	23.8 n	11.2 c	65.0 c
连粳7号 Lianjing 7	200	14.3 k	4.2 j	27.7 j	30.9 i	9.1 g	60.0 g
	300	23.3 h	6.0 h	45.1 g	31.3 h	8.1 j	60.6 f
	400	28.5 f	8.6 e	48.4 f	33.3 e	10.1 d	56.6 i
	500	33.6 d	11.8 b	51.4 d	34.7 c	12.2 b	53.1 k
扬稻6号 Yangdao 6	100	8.2 m	2.5 m	16.9 m	29.7 k	9.1 g	61.2 e
扬稻6号 Yangdao 6	200	18.5 j	4.7 i	33.9 i	32.4 f	8.2 i	59.4 h
	300	27.0 g	7.2 f	50.8 e	31.8 g	8.5 h	59.7 gh
	400	37.6 b	10.3 c	56.4 b	36.0 b	9.9 e	54.0 j
	500	48.6 a	15.3 a	56.5 b	40.4 a	12.7 a	46.9 l