外源色氨酸对低氮胁迫下高粱苗期叶片碳氮平衡和衰老特性的影响

doi:10.3864/j.issn.0578-1752.2023.07.008

摘要/Abstract

摘要：

【目的】研究外源色氨酸对低氮胁迫下高粱叶片衰老的影响，探讨低氮条件下高粱叶片碳氮平衡与衰老的关系，旨在挖掘高粱耐低氮胁迫的有效调控手段。【方法】选用耐低氮高粱自交系398B和氮敏感自交系CS3541为试验材料，采用水培试验，设置正常氮（5 mmol·L^-1）和低氮（0.5 mmol·L^-1）2个氮水平，并进行50 mg·L^-1外源色氨酸喷施处理，喷施10 d后测定叶片形态、组织结构、光合特性、叶绿素荧光参数、叶片碳氮代谢相关物质含量和酶活性、C/N及衰老相关基因表达水平，并分析低氮胁迫下高粱幼苗叶片C/N与衰老相关基因的相关性。【结果】（1）与正常氮水平相比，低氮胁迫显著降低了398B和CS3541的叶面积，而外源色氨酸处理使398B和CS3541的叶面积显著增加了36.72%和52.06%；外源色氨酸显著增加了低氮胁迫下398B和CS3541的叶干重和叶鲜重。（2）与正常氮水平相比，低氮胁迫下，398B花环结构相对完整，而外源色氨酸处理使叶片细胞排列整齐，花环结构清晰；外源色氨酸显著增加了低氮胁迫下398B叶片叶绿素含量（36.85%），而未显著提高CS3541叶片各色素含量。（3）低氮胁迫下，与未喷施色氨酸相比，外源色氨酸处理使叶片光系统II（PSII）表现出更高的最大光化学效率（F_v/F_m）和热耗散（NPQ），增加了叶片光合速率，从而维持叶片更强的光合能力。（4）外源色氨酸提高了低氮胁迫下高粱叶片氮含量和碳氮代谢相关酶活性；降低了高粱叶片碳水平（可溶性糖、蔗糖、淀粉和总糖）和C/N，进而保证低氮胁迫下植株的碳氮生理平衡。（5）外源色氨酸正调控低氮胁迫下衰老相关基因SbLHCB和SbSGR-2的表达，负调控SbNAC6、SbPaO3、SbPPDK-2和SbSAG12-2的表达；另外，C/N与SbLHCB和SbSGR-2表达量呈正相关，与SbNAC6、SbPaO3、SbPPDK-2和SbSAG12-2表达量呈负相关。【结论】低氮胁迫下，外源色氨酸通过降低C/N和衰老基因的表达量，影响叶片形态和光合特性，同时通过调节叶片碳氮代谢，延缓了叶片衰老，增强高粱幼苗对低氮胁迫的耐性。因此，喷施外源色氨酸是缓解低氮胁迫的一种潜在策略。

关键词: 高粱, 衰老相关基因, C/N, 光合特性, 碳氮代谢

Abstract:

【Objective】 The purpose of this study was to investigate the effects of exogenous tryptophan on senescence of sorghum (Sorghum bicolor L.) seedling leaves under low nitrogen stress, and to explore the relationship between C/N balance and senescence of sorghum seedlings leaves, so as to provide effective regulation means for sorghum resistance to low nitrogen stress. 【Method】 In a hydroponic culture experiment, the low nitrogen tolerance sorghum line (398B) and the low nitrogen sensitive sorghum line (CS3541) were selected as the experimental materials. Two nitrogen levels were set at normal nitrogen (5 mmol·L^-1) and low nitrogen (0.5 mmol·L^-1), and 50 mg·L^-1 exogenous tryptophan was applicated by spraying. After 10 days application, leaf morphology, tissue structure, photosynthetic activity, chlorophyll fluorescence parameters, content of carbon and nitrogen metabolism-related substances and enzyme activities, C/N and senescence related gene expression levels were determined, and the correlation between C/N and senescence genes in sorghum seedlings under low nitrogen stress was analyzed.【Result】 (1) Compared with the normal nitrogen treatment, low nitrogen stress significantly reduced the leaf area of 398B and CS3541, while exogenous tryptophan significantly increased the leaf area of 398B and CS3541 by 36.72% and 52.06%. Meanwhile, leaf dry weight and leaf fresh weight of 398B and CS3541 were significantly increased by exogenous tryptophan under low nitrogen stress. (2) Compared with the normal nitrogen treatment, the rosette structure of 398B was relatively complete under low nitrogen stress, while exogenous tryptophan kept the leaf cells orderly and the rosette structure clear. In addition, exogenous tryptophan significantly increased the chlorophyll content of 398B leaves (36.85%), but did not significantly increase the pigment content of CS3541 leaves under low nitrogen stress. (3) Under low nitrogen stress, the exogenous tryptophan treatment resulted in higher PSII maximum photochemical efficiency (F_v/F_m) and non-photochemical quenching (NPQ) capacity, increased leaf photosynthetic rate, and maintained stronger photosynthetic capacity than that without tryptophan. (4) The treatment with exogenous tryptophan reduced the accumulation of sugar (soluble sugar, sucrose and starch) in leaves, but significantly increased the nitrogen content in leaves, correspondingly increased the carbon and nitrogen metabolism enzymes activities, and decreased the C/N in leaves. (5) Exogenous tryptophan positively regulated the expressions of senescence related genes SbLHCB and SBSGR-2, and negatively regulated the expressions of SbNAC6, SbPaO3, SbPPDK-2 and SbSAG12-2 under low nitrogen conditions. In addition, C/N was positively correlated with the expression of SbLHCB and SbSGR-2, and negatively correlated with the expression of SbNAC6, SbPaO3, SbPPDK-2 and SbSAG12-2.【Conclusion】 Under low nitrogen stress, exogenous tryptophan affected leaf morphology and photosynthetic characteristics by reducing C/N and senescence gene expression, and delayed leaf senescence by regulating leaf carbon and nitrogen metabolism, thus enhancing the tolerance of sorghum seedlings under low nitrogen stress. Tryptophan application would be a strategy to weaken low nitrogen stress in the future sustainable agricultural production.

Key words: Sorghum bicolor L., senescence related gene, C/N, photosynthetic activity, carbon and nitrogen metabolism

谷闻东, 刘春娟, 李邦, 刘畅, 周宇飞. 外源色氨酸对低氮胁迫下高粱苗期叶片碳氮平衡和衰老特性的影响[J]. 中国农业科学, 2023, 56(7): 1295-1310.

GU WenDong, LIU ChunJuan, LI Bang, LIU Chang, ZHOU YuFei. Effects of Exogenous Tryptophan on C/N Balance and Senescence Characteristics of Sorghum Seedlings Under Low Nitrogen Stress[J]. Scientia Agricultura Sinica, 2023, 56(7): 1295-1310.

0
/ / 推荐

导出引用管理器 EndNote|Reference Manager|ProCite|BibTeX|RefWorks

链接本文: https://www.chinaagrisci.com/CN/10.3864/j.issn.0578-1752.2023.07.008

https://www.chinaagrisci.com/CN/Y2023/V56/I7/1295

图/表 14

表1

图1

图2

表2

图3

图4

图5

图6

图7

图8

图9

图10

图11

图12

参考文献 51

[1]	KUSANO M, FUKUSHIMA A, REDESTIG H, SAITO K. Metabolomic approaches toward understanding nitrogen metabolism in plants. Journal of Experimental Botany, 2011, 62(4): 1439-1953. doi: 10.1093/jxb/erq417 pmid: 21220784
[2]	祝令晓, 宋世佳, 李浩然, 孙红春, 张永江, 白志英, 张科, 李安昌, 刘连涛, 李存东. 基于耐低氮综合指数的棉花苗期耐低氮自交系筛选. 作物学报, 2022, 48(7): 1800-1812. doi: 10.3724/SP.J.1006.2022.14085
	ZHU L X, SONG S J, LI H R, SUN H C, ZHANG Y J, BAI Z Y, ZHANG K, LI A C, LIU L T, LI C D. Screening of low nitrogen tolerant cultivars based on low nitrogen tolerance comprehensive index at seeding stage in cotton. Acta Agronomica Sinica, 2022, 48(7): 1800-1812. (in Chinese)
[3]	WEN B B, LI C, FU X L, LI D M, LI L, CHEN X D, WU H Y, CUI X W, ZHANG X H, SHEN H Y, ZHANG W Q, XIAO W, GAO D S. Effects of nitrate deficiency on nitrate assimilation and chlorophyll synthesis of detached apple leaves. Plant Physiology and Biochemistry, 2019, 142: 363-371. doi: S0981-9428(19)30286-4 pmid: 31398585
[4]	宫香伟, 韩浩坤, 张大众, 李境, 王孟, 薛志和, 杨璞, 高小丽, 冯佰利. 氮肥运筹对糜子生育后期干物质积累与转运及叶片氮素代谢的调控效应. 中国农业科学, 2018, 51(6): 1045-1056. doi: 10.3864/j.issn.0578-1752.2018.06.004
	GONG X W, HAN H K, ZHANG D Z, LI J, WANG M, XUE Z H, YANG P, GAO X L, FENG B L. Effects of nitrogen fertilizer on dry matter accumulation, transportation and nitrogen metabolism in functional leaves of broomcorn millet at late growth stage. Scientia Agricultura Sinica, 2018, 51(6): 1045-1056. (in Chinese)
[5]	LIU C J, GONG X W, WANG H L, DANG K, DENG X P, FENG B L. Low-nitrogen tolerant comprehensive evaluation and physiological response to nitrogen stress in broomcorn millet (Panicum miliaceum L.) seedling. Plant Physiology and Biochemistry, 2020, 151: 233-242. doi: 10.1016/j.plaphy.2020.03.027
[6]	GONG X W, LI J, MA H C, CHEN G H, DANG K, YANG P, WANG M, FENG B L. Nitrogen deficiency induced a decrease in grain yield related to photosynthetic characteristics, carbon-nitrogen balance and nitrogen use efficiency in proso millet (Panicum miliaceum L.). Archives of Agronomy and Soil Science, 2019, 66(3): 398-413. doi: 10.1080/03650340.2019.1619077
[7]	严雯奕, 叶胜海, 董彦君, 金庆生, 张小明. 植物叶片衰老相关研究进展. 作物杂志, 2010, 26(4): 4-9.
	YAN W Y, YE S H, DONG Y J, JIN Q S, ZHANG X M. Research progress related to plant leaf senescence. Crops, 2010, 26(4): 4-9. (in Chinese)
[8]	MARTIN T, OSWALD O, GRAHAM I A. Arabidopsis seedling growth, storage lipid mobilization, and photosynthetic gene expression are regulated by Carbon: Nitrogen availability. Plant Physiology, 2002, 128(2): 472-481. doi: 10.1104/pp.010475
[9]	王宁, 师赵康, 徐世英, 尹凤茹, 王伟杰, 冯万军. 低氮诱导玉米幼苗叶片衰老过程中碳氮平衡的动态变化. 应用生态学报, 2022, 33(4): 1045-1054. doi: 10.13287/j.1001-9332.202204.034
	WANG N, SHI Z K, XU S Y, YIN F R, WANG W J, FENG W J. Dynamic changes of carbon and nitrogen balance during leaf senescence of maize seedlings induced by low nitrogen stress. Chinese Journal of Applied Ecology, 2022, 33(4): 1045-1054. (in Chinese) doi: 10.13287/j.1001-9332.202204.034
[10]	曹蓓蓓, 王仕稳, 齐凌云, 陈道钳, 殷俐娜, 邓西平. 小麦苗期叶片碳氮平衡与低氮诱导的叶片衰老之间的关系. 麦类作物学报, 2017, 37(5): 673-679.
	CAO B B, WANG S W, QI L Y, CHEN D Q, YIN L N, DENG X P. Carbon/nitrogen balance involved in nitrogen deficiency induced leaf senescence in wheat seedling. Journal of Triticeae Crops, 2017, 37(5): 673-679. (in Chinese)
[11]	周琴, 赵超鹏, 曹春信, 江巧君, 江海东. 不同氮肥基追比对多花黑麦草碳氮转运和种子产量的影响. 草业学报, 2010, 19(4): 47-53.
	ZHOU Q, ZHAO C P, CAO C X, JIANG Q J, JIANG H D. Effects of N dressing ratio on carbon and nitrogen transport and on grain yield of Lolium multiflorum. Acta Prataculturae Sinica, 2010, 19(4): 47-53. (in Chinese)
[12]	PALENCHAR P M, KOURANOV A, LEJAY L V, CORUZZI G M. Genome-wide patterns of carbon and nitrogen regulation of gene expression validate the combined carbon and nitrogen (CN)-signaling hypothesis in plants. Genome Biology, 2004, 5(11): 1-15.
[13]	MUSTAFA A, IMRAN M, ASHRAF M, MAHMOOD K. Perspectives of using l-tryptophan for improving productivity of agricultural crops: A review. Pedosphere, 2018, 28(1): 16-34. doi: 10.1016/S1002-0160(18)60002-5
[14]	ZHANG T T, KANG H, FU L L, SUN W J, GAO W S, YOU C X. WANG X F. HAO Y J. Nin-like protein 7 promotes nitrate- mediated lateral root development by activating transcription of TRYPTOPHAN AMINOTRANSFERASE RELATED 2. Plant Science, 2021, 303: 1-11.
[15]	ZAHIR Z A, ASGHAR H N, AKHTAR M J, ARSHAD M. Precursor (L-tryptophan)-inoculum (Azotobacter) interaction for improving yields and nitrogen uptake of maize. Journal of Plant Nutrition, 2005, 28(5): 805-817. doi: 10.1081/PLN-200055543
[16]	ETESAMI H, ALIKHANI H A, JADIDI M, ALIAKBARI A. Effect of superior IAA producing rhizobia on N, P, K uptake by wheat grown under greenhouse condition. World Applied Sciences Journal, 2009, 6(12): 1629-1633.
[17]	EL-AWADI M E, EL-BASSINOY A M, FAWZY Z F, EL-NEMR M A. Response of snap bean (Phaseolus Vulgaris L.) plants to nitrogen fertilizer and foliar application with methionine and tryptophan. Nature and Science, 2011, 9(5): 87-94.
[18]	DAWOOD M G, SADAK M S. Physiological responses of wheat to salinity alleviation by nicotinamide and tryptophan. International Journal of Agriculture and Biology, 2005, 7: 653-659.
[19]	邹剑秋. 高粱育种与栽培技术研究新进展. 中国农业科学, 2020, 53(14): 2769-2773. doi: 10.3864/j.issn.0578-1752.2020.14.001
	ZOU J Q. New research progress on sorghum breeding and cultivation techniques. Scientia Agricultura Sinica, 2020, 53(14): 2769-2773. (in Chinese) doi: 10.3864/j.issn.0578-1752.2020.14.001
[20]	赵明辉, 孙建, 王嘉宇, 徐海, 唐亮, 陈温福. 全基因组分析低氮胁迫下水稻剑叶光合相关基因表达变化. 中国农业科学, 2011, 44(1): 1-8.
	ZHAO M H, SUN J, WANG J Y, XU H. TANG L, CHEN W F. Global genome expression Aanalysis of photosynthesis-related genes under low nitrogen stress in rice flag leaf. Scientia Agricultura Sinica, 2011, 44(1): 1-8. (in Chinese)
[21]	张定一, 张永清, 杨武德, 苗果园. 不同基因型小麦对低氮胁迫的生物学响应. 作物学报, 2006, 32(9): 1349-1354.
	ZHANG D Y, ZHANG Y Q, YANG W D, MIAO G Y. Biological response of roots in different spring wheat genotypes to low nitrogen stress. Acta Agronomica Sinica, 2006, 32(9): 1349-1354. (in Chinese)
[22]	赵泽群, 师赵康, 王雯, 张远航, 徐世英, 王宁, 王伟杰, 程皓, 冯万军. 低氮胁迫下玉米幼苗氮素和蔗糖分配特性. 植物营养与肥料学报, 2020, 26(4): 783-796.
	ZHAO Z Q, SHI Z K, WANG W, ZHANG Y H, XU S Y, WANG N, WANG W J. CHENG H, FENG W J. Allocation of nitrogen and sucrose in maize seedling under low nitrogen stress. Journal of Plant Nutrition and Fertilizers, 2020, 26(4): 783-796. (in Chinese)
[23]	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, 123-194.
	LI H S. Principles and Techniques of Plant Physiology and Biochemistry Experiments. Beijing: Higher Education Publishers, 2000, 123-194. (in Chinese)
[24]	SCHRADER S, SAUTER J J. Seasonal changes of sucrose-phosphate synthase and sucrose synthase activities in poplar wood (Populus Canadensis Moench ‘robusta’) and their possible role in carbohydrate metabolism. Journal of Plant Physiology, 2002, 159(8): 833-843. doi: 10.1078/0176-1617-00730
[25]	NOMURA T, AKAZAWA T. Enzymic mechanism of starch synthesis in ripening rice grains: VII. Purification and enzymic properties of sucrose synthetase. Archives of Biochemistry and Biophysics, 1973, 156(2): 644-652. doi: 10.1016/0003-9861(73)90316-0
[26]	PRESSEY R. Potato sucrose synthetase: purification, properties, and changes in activity associated with maturation. Plant Physiology, 1969, 44(5): 759-764. doi: 10.1104/pp.44.5.759 pmid: 16657128
[27]	GONG X W, LIU C J, FERDINAND U, DANG K, ZHAO G, YANG P, FENG B L. Effect of intercropping on leaf senescence related to physiological metabolism in proso millet (Panicum miliaceum L.). Photosynthetica, 2019, 57(4): 993-1006. doi: 10.32615/ps.2019.112
[28]	郭改玲, 刘克礼, 高聚林, 张永平, 郝德春, 史建国. 氮素施用方式对春小麦花后叶片衰老与产量的影响. 麦类作物学报, 2006, 26(5), 126-129.
	GUO G L, LIU K L, GAO J L, ZHANG Y P, HE D C, SHI J G. Effect of nitrogen application on flag leaf senescence and yield of spring wheat. Journal of Triticeae Crops, 2006, 26(5), 126-129. (in Chinese)
[29]	IRAM S, SAJAD H, MUHAMMAD A R, NASIR I, MUHAMMAD A A, ALI R, FAN Y, MARYAM M, MUHAMMAD S, MUHAMMAD A, ABDUL M, YANG W, YANG F. Crop photosynthetic response to light quality and light intensity. Journal of Integrative Agriculture, 2021, 20(1): 4-23. doi: 10.1016/S2095-3119(20)63227-0
[30]	CHEN X F, ZHANG R D, XING Y F, JIANG B, LI B, XU X X, ZHOU Y F. The efficacy of different seed priming agents for promoting sorghum germination under salt stress. PLoS ONE, 2021, 16(1): e2045505.
[31]	张瑞栋, 肖梦颖, 徐晓雪, 姜冰, 邢艺凡, 陈小飞, 李邦, 艾雪莹, 周宇飞, 黄瑞冬. 高粱种子对萌发温度的响应分析与耐低温萌发能力鉴定. 作物学报, 2020, 46(6): 889-901. doi: 10.3724/SP.J.1006.2020.94150
	ZHANG R D, XIAO M Y, XU X X, JIANG B, XING Y F, CHEN X F, LI B, AI X Y, ZHOU Y F, HUANG R D. Responses of sorghum hybrids to germination temperatures and identification of low temperature resistance. Acta Agronomica Sinica, 2020, 46(6): 889-901. (in Chinese) doi: 10.3724/SP.J.1006.2020.94150
[32]	JING Y J, CUI D Y, BAO F, HU Z B, QIN Z X, HU Y X. Tryptophan deficiency affects organ growth by retarding cell expansion in Arabidopsis. The Plant Journal, 2009, 57(3): 511-521. doi: 10.1111/tpj.2009.57.issue-3
[33]	SIMKIN A J, KAPOOR L, DOSS C G P, HOFMANN T A, LAWSON T, RAMAMOORTHY S. The role of photosynthesis related pigments in light harvesting, photoprotection and enhancement of photosynthetic yield in planta. Photosynthesis Research, 2022, 152(1): 23-42. doi: 10.1007/s11120-021-00892-6
[34]	赵霞. 水稻叶片非光化学猝灭对环境因子的光合响应[D]. 武汉: 华中农业大学, 2017.
	ZHAO X. Photosynthetic response of non-photochemical quenching to environmental factors in rice leaf[D]. Wuhan: Huazhong Agriculture University, 2017. (in Chinese)
[35]	HUANG D, WU L, CHEN J R, DONG L. Morphological plasticity, photosynthesis and chlorophyll fluorescence of Athyrium pachyphlebium at different shade levels. Photosynthetica, 2011, 49(4): 611-618. doi: 10.1007/s11099-011-0076-1
[36]	LI Y T, YANG C, ZHANG Z S, ZHAO S J, GAO H Y. Photosynthetic acclimation strategies in response to intermittent exposure to high light intensity in wheat (Triticum aestivum L.). Environmental and Experimental Botany, 2021, 181: e104275.
[37]	苏纪勇, 姚圆, 刘玉含, 韩秋宇, 张雯露. 蔗糖磷酸合酶功能、结构与催化机制的研究进展. 生物工程学报, 2021, 37(6): 1858-1868.
	SU J Y, YAO Y, LIU Y H, HAN Q Y, ZHANG W L. Function, structure and catalytic mechanism of sucrose. Chinese Journal of Biotechnology, 2021, 37(6): 1858-1868. (in Chinese)
[38]	房经贵, 朱旭东, 贾海锋, 王晨. 植物蔗糖合酶生理功能研究进展. 南京农业大学学报, 2017, 40(5): 759-768.
	FANG J G, ZHU X D, JIA H F, WANG C. Research advances on physiological function of plant sucrose synthase. Journal of Nanjing Agricultural University, 2017, 40(5): 759-768. (in Chinese)
[39]	YANG M, GENG M Y, SHEN P F, CHEN X H, LI Y J, WEN X X. Effect of post-silking drought stress on the expression profiles of genes involved in carbon and nitrogen metabolism during leaf senescence in maize (Zea mays L.). Plant Physiology Biochemistry, 2018, 135: 304-309. doi: 10.1016/j.plaphy.2018.12.025
[40]	WINGLER A, DELATTE T L, O'HARA L E, PRIMAVESI L F, JHURREEA D, PAUL M J, SCHLUEPMANN H. Trehalose 6-phosphate is required for the onset of leaf senescence associated with high carbon availability. Plant Physiology, 2012, 158: 1241-1251. doi: 10.1104/pp.111.191908 pmid: 22247267
[41]	STETTLER M, EICKE S, METTLER T, MESSERLI G, HÖRTENSTEINER S, ZEEMAN S C. Blocking the metabolism of starch breakdown products in Arabidopsis leaves triggers chloroplast degradation. Molecular Plant, 2009, 2(6): 1233-1246. doi: 10.1093/mp/ssp093
[42]	WU K, WANG S S, SONG W Z, ZHANG J Q, WANG Y, LIU Q, YU J P, YE Y F, LI S, CHEN J F, ZHAO Y, WANG J, WU X K, WANG M Y, ZHANG Y J, LIU B M, WU Y J, HARBERD N P, FU X D. Enhanced sustainable green revolution yield via nitrogen-responsive chromatin modulation in rice. Science, 2020, 367: 1-9.
[43]	肖燕, 姚珺玥, 刘冬, 宋海星, 张振华. 甘蓝型油菜响应低氮胁迫的表达谱分析. 作物学报, 2020, 46(10): 1526-1538. doi: 10.3724/SP.J.1006.2020.94197
	XIAO Y, YAO J Y, LIU D, SONG H X, ZHANG Z H. Expression profile analysis of low nitrogen stress in Brassica napus. Acta Agronomica Sinica, 2020, 46(10): 1526-1538. (in Chinese) doi: 10.3724/SP.J.1006.2020.94197
[44]	WANG Z N, LU J Y, MEI Y, YANG H M, ZHANG Q P. Stoichiometric characteristics of carbon, nitrogen, and phosphorus in leaves of differently aged lucerne (Medicago sativa) stands. Frontiers in Plant Science, 2015, 6: 1-10.
[45]	BI Z Z, ZHANG Y X, WU W X, ZHAN X D, YU N, XU T T, LIU Q E, LI Z, SHEN X H, CHEN D B, CHENG S H, CAO L Y. ES7, encoding a ferredox independent glutamate synthase, functions in nitrogen metabolism and impacts leaf senescence in rice. Plant Science, 2017, 259: 24-34. doi: 10.1016/j.plantsci.2017.03.003
[46]	李邦. 低氮胁迫下外源色氨酸调控高粱幼苗根系伸长的机制研究[D]. 沈阳: 沈阳农业大学, 2022.
	LI B. Regulation mechanism of exogenous Tryptophan on root elongation of sorghum seedlings under low nitrogen stress[D]. Shenyang: Shenyang Agricultural University, 2022. (in Chinese)
[47]	NING P, PENG Y F, FRITSCHI F B. Carbohydrate dynamics in maize leaves and developing ears in response to nitrogen application. Agronomy, 2018, 302(8): 1-14.
[48]	CHEN D Q, WANG S W, XIONG B L, CAO B B, DENG X P. Carbon/nitrogen imbalance associated with drought-induced leaf senescence in sorghum bicolor. PLoS ONE, 2015, 10(8): 1-17.
[49]	黄瑞冬, 孙璐, 肖木辑, 许文娟, 周宇飞. 持绿型高粱B35灌浆期对干旱的生理生化响应. 作物学报, 2009, 35(3): 560-565.
	HUANG R D, SUN L, XIAO M J, XU W J, ZHOU Y F. Physiological and biochemical responses to drought during filling stage in stay green Sorghum B35. Acta Agronomica Sinica, 2009, 35(3): 560-565. (in Chinese) doi: 10.3724/SP.J.1006.2009.00560
[50]	SHI S Y, MIAO H Y, DU X M, GU J T, XIAO K. GmSGR1, a stay-green gene in soybean (Glycine max L.), plays an important role in regulating early leaf-yellowing phenotype and plant productivity under nitrogen deprivation. Acta Physiologiae Plantarum, 2016, 38(4): 97-111. doi: 10.1007/s11738-016-2105-y
[51]	DE BIANCHI S, DALL'OSTO L, TOGNON G, MOROSINOTTO T, BASSI R. Minor antenna proteins CP24 and CP26 affect the interactions between photosystem II subunits and the electron transport rate in grana membranes of Arabidopsis. The Plant Cell, 2008, 20(4): 1012-1028. doi: 10.1105/tpc.107.055749

基因名称 Gene name	引物名称 Primer name	引物序列 Primer sequence (5′-3′)
SbGAPDH	GAPDH-F	GTGTTTGGACTTCTTGGGGGA
SbGAPDH	GAPDH-R	TCATCTCGGGGATCTCTGCC
SbPaO	PaO-F3	CTGCCACCAAGCTCTACCAA
SbPaO	PaO-R3	GAACAACCGACGTGAGCAAC
SbPPDK	PPDK-F2	CAGGCTTACCTGCATCACCA
SbPPDK	PPDK-R2	TTGAGCATCCTGCCACACAA
SbSAG12	SAG12-F2	CGCCTCTATGCTCCGCAATA
SbSAG12	SAG12-R2	CAACCAGTGCAGACAACAGC
SbSGR	SGR-F2	GGCCTCCGCTACTACATCTT
SbSGR	SGR-R2	GGGTCAGGTTGGAGTGGAAG
SbNAC6	NAC6-F	GGCCCTCTTGCTGATGAGTT
SbNAC6	NAC6-R	ACTGTCATCCACTTGGCGAG
SbLHCB	LHCB-F	CGCCAAGTTCGAGGAGTACA
SbLHCB	LHCB-R	TCTGGGGATGATGATGTCGC

处理 Treatment	自交系 Inbred line	叶绿素a Chl a (mg·g^-1)	叶绿素b Chl b (mg·g^-1)	类胡萝卜素 Car (mg·g^-1)	叶绿素含量 Chl (mg·g^-1)
NTrp	398B-NN	2.38±0.06c	0.51±0.01bc	0.49±0.01b	2.89±0.08b
	399B-LN	1.60±0.09e	0.33±0.10d	0.31±0.01d	1.93±0.18e
	CS3541-NN	2.12±0.05d	0.47±0.11bc	0.45±0.03c	2.59±0.14d
	CS3541-LN	1.27±0.05g	0.20±0.02e	0.30±0.01d	1.47±0.07f
Trp	398B-NN	2.50±0.04b	0.59±0.07bc	0.49±0.01b	3.09±0.10a
	399B-LN	2.19±0.06d	0.45±0.07c	0.48±0.01bc	2.64±0.13c
	CS3541-NN	3.41±0.06a	0.71±0.02a	0.70±0.01a	4.12±0.09a
	CS3541-LN	1.44±0.03f	0.19±0.01e	0.33±0.01d	1.63±0.04f