《植物生理学报》 2021, 57(3): 632-642

一氧化氮介导水杨酸诱导的采后杧果果实炭疽病抗性反应

任艳芳^1,2,*，宋雅萍¹，肖桂云²，张黎明¹，何俊瑜^1,2,*，林肖²，王艳玲²

¹常州大学环境与安全工程学院, 江苏常州213164；²贵州大学农学院, 贵阳550025

通信作者：任艳芳；E-mail: yanfangren@126.com；何俊瑜；E-mail: junyuhe0303@126.com

摘　要：

为明确一氧化氮(NO)是否参与水杨酸(SA)诱导的采后杧果(Mangifera indica)果实抗病反应及其调控机制, 以‘台农’杧果为材料, 采用外源SA结合NO清除剂——2-(4-羧苯基)-4,4,5,5-四甲基咪唑啉-1-烃氧基-3-氧化钠盐(cPTIO)、一氧化氮合酶(NOS)抑制剂——N ω-硝基-l-精氨酸甲酯(L-NAME)和硝酸还原酶(NR)抑制剂——叠氮化钠(NaN₃)处理果实, 测定不同处理对果实上接种炭疽病菌Colletotrichum gloeosporioides生长、果实中抗病物质和NO含量以及抗病相关酶、 NOS和NR活性的影响。结果表明: SA处理明显降低了杧果果实上炭疽病的病斑直径, 延缓发病进程; SA处理明显增强了NOS活性, 提高了接种后前期NO含量, 同时明显提高了接种果实中苯丙氨酸转氨酶(PAL)、多酚氧化酶(PPO)、 β-1,3-葡聚糖酶(GLU)、几丁质酶(CHI)、肉桂酸-4-羟化酶(C4H)、对香豆酰-CoA连接酶(4-CL)活性, 促进了木质素、类黄酮和总酚的积累。与单独SA处理相比, SA结合cPTIO或L-NAME处理在降低NO含量的同时削弱了SA对杧果果实炭疽病抗性的诱导作用, 而NaN3对SA处理后杧果果实炭疽病抗性诱导作用无明显影响。因此, NO主要通过NOS途径参与SA诱导的采后杧果炭疽病抗性。

关键词：杧果; 水杨酸; 一氧化氮; 抗病反应; NOS途径

收稿：2020-10-09   修定：2021-01-07

资助：国家自然科学基金(31660477和31360413)、常州大学人才引进项目(201709和201710)和贵州省科技计划项目(黔科合平台人才 [2017]5788号)

Nitric oxide mediates salicylic acid-induced defense responses in mango fruit against anthracnose disease

REN Yanfang^1,2,*, SONG Yaping¹, XIAO Guiyun², ZHANG Liming¹, HE Junyu^1,2,*, LIN Xiao², WANG Yanling²

¹School of Environmental and Safety Engineering, Changzhou University, Changzhou, Jiangsu 213164, China; ²College of Agriculture, Guizhou University, Guiyang 550025, China

Corresponding author: REN Yanfang; E-mail: yanfangren@126.com; HE Junyu; E-mail: junyuhe0303@126.com

Abstract:

To investigate whether nitric oxide (NO) is involved in defense responses in mango (Mangifera indica) fruit against anthracnose disease induced by salicylic acid (SA) and its possible mechanism, ‘Tainong’ mango fruits were treated with exogenous SA combined with NO scavenger, 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (cPTIO), nitric oxide synthase (NOS) inhibitor, Nω-nitro-l-arginine methyl ester (L-NAME), and nitrate reductase (NR) inhibitor, sodium azide (NaN₃). The effects of different treatments on the growth of lesion diameter, contents of antimicrobial compounds and NO, and activities of defense-related enzymes, NOS and NR in mango fruits inoculated with Colletotrichum gloeosporioides were determined. The results show that SA signifcantly reduced the lesion diameter of mango fruits inoculated with C. gloeosporioides and delayed the progress of anthracnose disease. SA signifcantly enhanced NOS activity and increased NO content in the fruits at the early stage after inoculation. Moreover, SA signifcantly increased the activities of phenylalanine ammonia-lyase (PAL), polyphenoloxidase (PPO), cinnamate 4-hydroxylase (C4H), 4-coumarate CoA ligase (4-CL), β-1,3-glucanase (GLU) and chitinase (CHI), and promoted the accumulation of lignin, flavonoids and total phenolic compounds in the fruits inoculated with pathogen. Compared with SA treatment, SA combined with cPTIO or L-NAME reduced the NO content and weakened SA-induced defense against anthracnose disease in mango fruit. However, NaN3 treatment had no signifcant negative effect on the induction of mango anthracnose resistance by SA. Therefore, NO mainly produced through NOS pathway is involved in SA-induced disease resistance in mango fruits.

Key words: Mangifera indica; salicylic acid; nitric oxide; defense response; NOS pathway