中国农业科学 ›› 2020, Vol. 53 ›› Issue (15): 3095-3107.doi: 10.3864/j.issn.0578-1752.2020.15.010

• 植物保护 • 上一篇    下一篇

小麦、玉米两熟秸秆还田土壤中6种有机酸对小麦纹枯病的化感作用

赵绪生1,2(),齐永志1,2(),闫翠梅1,2,甄文超2,3,4()   

  1. 1河北农业大学植物保护学院,河北保定 071001
    2省部共建华北作物改良与调控国家重点实验室,河北保定 071001
    3河北农业大学农学院,河北保定 071001
    4河北省作物生长调控重点实验室,河北保定 071001
  • 收稿日期:2020-02-29 接受日期:2020-04-02 出版日期:2020-08-01 发布日期:2020-08-06
  • 通讯作者: 甄文超
  • 作者简介:赵绪生,E-mail: zhaoxusheng2000@yeah.net。|齐永志,E-mail: qiyongzhi1981@163.com
  • 基金资助:
    国家重点研发计划(2017YFD0300906);国家科技支撑计划(2012BAD04B06);河北省教育厅项目(ZD2016162);河北省自然科学基金(C2016204211);河北省现代农业产业技术体系小麦产业技术创新团队建设项目(HBCT2018010205)

Allelopathy of Six Organic Acids on Wheat Sheath Blight in the Soil of Winter Wheat-Summer Maize Double Cropping Straw Returning System

ZHAO XuSheng1,2(),QI YongZhi1,2(),YAN CuiMei1,2,ZHEN WenChao2,3,4()   

  1. 1College of Plant Protection, Hebei Agricultural University, Baoding 071001, Hebei
    2State Key Laboratory for Crop Improvement and Control in North China, Baoding 071001, Hebei
    3College of Agronomy, Hebei Agricultural University, Baoding 071001, Hebei
    4Hebei Key Laboratory of Crop Growth Control, Baoding 071001, Hebei
  • Received:2020-02-29 Accepted:2020-04-02 Online:2020-08-01 Published:2020-08-06
  • Contact: WenChao ZHEN

摘要:

【目的】冬小麦、夏玉米一年两熟是中国北方最广泛的农作制度,中国北方小麦、玉米生产普遍采用秸秆还田的耕作方式,关于秸秆还田对小麦土传病害的影响一直存在争议。通过分析不同秸秆还田年限地块耕层土壤中的主要有机酸对小麦幼苗生长、禾谷丝核菌(Rhizoctonia cerealis)及纹枯病发生的化感作用,明确我国北方冬小麦、夏玉米一年两熟种植体系下秸秆还田对小麦纹枯病发生的影响。【方法】利用GC-MS技术分析玉米秸秆还田地块耕层土壤乙酸乙酯提取物中化学物质的种类与含量,并分别用氯化三苯基四氮唑(TTC)还原法、电导率法、氮蓝四唑光化(NBT)还原法和愈创木酚比色法测定含量较高的6种有机酸对小麦幼苗根系活力、根系细胞膜透性、超氧化物歧化酶(SOD)和过氧化物酶(POD)活性的影响,用常规方法测定其对禾谷丝核菌和纹枯病发生的影响。【结果】秸秆还田地块耕层土壤中含有机酸、烷烃、醇、酰胺及醛类等化学物质,相对含量分别为45.45%、17.70%、17.08%、6.12%和5.44%;含量较高的有机酸类物质包括邻羟基苯甲酸(9.24%)、3-苯基-2-丙烯酸(4.12%)、对羟基苯甲酸(3.21%)、4-羟基-3,5-二甲氧基苯甲酸(2.26%)、二十一烷酸(1.88%)、4-甲氧基邻氨基苯甲酸(1.73%)、8-十八碳烯酸(0.76%)和3-(4-羟基-3-甲氧基苯基)-2-丙烯酸(0.52%)。0.08—10.0 μg·mL-1浓度的4-甲氧基邻氨基苯甲酸和3-(4-羟基-3-甲氧基苯基)-2-丙烯酸对禾谷丝核菌的菌丝生长(10.0 μg·mL-14-甲氧基邻氨基苯甲酸除外)、菌丝干重和菌核数量均表现明显促进作用,且2种物质在土壤中的含量均随秸秆还田年限延长呈增多趋势。0.4和0.08 μg·mL-1邻羟基苯甲酸对禾谷丝核菌的菌丝生长和菌核形成有明显促进作用;而50.0 μg·mL-1邻羟基苯甲酸和4-羟基-3-甲氧基-苯甲酸,以及0.4—50.0 μg·mL-1苯甲酸均表现为抑制作用。在2.0—50.0 μg·mL-1浓度范围内,随着6种有机酸浓度的提高,其对小麦幼苗生长的抑制作用越强,对羟基苯甲酸抑制作用最强,其次是邻羟基苯甲酸,4-甲氧基邻氨基苯甲酸最弱。0.4—50.0 μg·mL-1浓度的3-(4-羟基-3-甲氧基苯基)-2-丙烯酸、4-甲氧基邻氨基苯甲酸、邻羟基苯甲酸和对羟基苯甲酸均加重小麦纹枯病发生,其中,3-(4-羟基-3-甲氧基苯基)-2-丙烯酸助长作用最强,发病率和病情指数最高增幅分别达49.0%和46.7%;而苯甲酸和4-羟基-3-甲氧基-苯甲酸对小麦纹枯病发生无显著影响。【结论】冬小麦、夏玉米一年两熟秸秆还田土壤中含有机酸、酯、烃、酰胺及醛类等化学物质,有机酸类物质相对含量最高。3-(4-羟基-3-甲氧基苯基)-2-丙烯酸、4-甲氧基邻氨基苯甲酸、邻羟基苯甲酸和对羟基苯甲酸在一定浓度下均可助长小麦纹枯病的发生,其中3-(4-羟基-3-甲氧基苯基)-2-丙烯酸助长作用最强,而苯甲酸和4-羟基-3-甲氧基-苯甲酸对纹枯病发生无明显影响。还田秸秆在土壤中腐解产生的有机酸类物质促进病原菌生长、抑制小麦根系生理活性和生长的化感作用,可能是中国北方小麦、玉米两熟秸秆还田条件下小麦纹枯病加重发生的主要原因之一。

关键词: 秸秆还田, 小麦纹枯病, 禾谷丝核菌, GC-MS, 化感作用, 有机酸

Abstract:

【Objective】Double cropping of winter wheat and summer maize is the most extensive farming system in northern China. Straw returning has been widely used in wheat and maize production. But, the effect of straw returning on the occurrence of soil borne diseases of wheat has been controversial. The objective of this study is to analyze the main chemical constituents in the cultivated-layer soil with different straw returning years and the allelopathic effects of the main organic acids on the growth of wheat seedlings, the mycelium growth and sclerotia formation of Rhizoctonia cerealis and occurrence of wheat sheath blight (WSB), and to understand the relationship between straw returning and WSB incidence.【Method】Gas chromatography-mass spectrometry (GC-MS) technique was used to analyze the types and contents of chemical substances in the extract of ethyl acetate from the cultivated soil where maize straw returning, and the effects of 6 organic acids with higher content on the root activity, root cell membrane permeability, superoxide dismutase (SOD) and peroxidase (POD) activity of wheat seedlings were determined with the TTC reduction, electrical conductivity, NBT photoreduction and guaiacol colorimetry methods, respectively. Meanwhile, the effects of these organic acids on the mycelium growth, sclerotium formation and occurrence of WSB were determined by the conventional methods.【Result】The relative contents of organic acids, alkanes, alcohols, amides, and aldehydes in the cultivated-layer soil and straw returning were 45.45%, 17.70%, 17.08%, 6.12%, and 5.44%, respectively. Organic acids mainly included o-hydroxybenzoic acid (9.24%), 3-phenyl-2-acrylic acid (4.12%), p-hydroxybenzoic acid (3.21%), 4-hydroxy-3,5- dimethoxybenzoic acid (2.26%), heneicosanoic acid (1.88%), 4-methoxy-anthranilic acid (1.73%), 8-octadecanoic acid (0.76%) and 3-(4-hydroxy-3- methoxyphenyl)-2-acrylic acid (0.52%). 4-methoxy-anthranilic acid and 3-(4-hydroxy-3-methoxyphenyl)-2-acrylic acid at 0.08-10.0 μg·mL-1had significant promoting effects on mycelial growth (expect 4-methoxy-anthranilic acid at 10.0 μg·mL-1), dry weight and sclerotium formation of R. cerealis, and the relative content of the two substances increased with the extension of straw returning years. O-hydroxybenzoic acid significantly promoted mycelial growth and sclerotia formation of R. cerealis at 0.4 and 0.08 μg·mL-1. In contrast, 50.0 μg·mL-1 of o-hydroxybenzoic acid and 4-hydroxyl-3-methoxy-benzoic acid, and 0.4-50.0 μg·mL-1 of benzoic acid all showed inhibitory effects. All 6 organic acids at concentrations of 2.0-5.0 μg·mL-1 inhibited the growth of wheat seedlings in a dose-dependent manner. The inhibitory effect of p-hydroxybenzoic acid was the strongest, followed by o-hydroxybenzoic acid, and 4-methoxy-anthranilic acid was the weakest. 3-(4-hydroxy-3-methoxyphenyl)-2-acrylic acid, 4-methoxyanthranilic acid, o-hydroxybenzoic acid, and p-hydroxybenzoic acid at concentrations of 0.4-50.0 μg·mL-1 aggravated the occurrence of WSB. 3-(4-hydroxy-3-methoxyphenyl)-2-acrylic acid had the strongest enhancing effect, with the incidence and disease index increased by 49.0% and 46.7%, respectively. Benzoic acid and 4-hydroxy-3-methoxyphenyl-benzoic acid had no significant effect on the occurrence of WSB.【Conclusion】Organic acids, esters, hydrocarbons, amides, and aldehydes were found in the cultivated-layer soil in the winter wheat-summer maize double cropping straw returning system. Organic acids were the most abundant of those chemicals. 3-(4-hydroxy-3-methoxyphenyl)-2-acrylic acid, 4-methoxyanthranilic acid, o-hydroxybenzoic acid, and p-hydroxybenzoic acid at a certain concentration can promote the occurrence of WSB. 3-(4-hydroxy-3-methoxyphenyl)-2-acrylic acid has the strongest stimulatory effect, while benzoic acid and 4-hydroxy-3-methoxy-benzoic acid have no effect on the occurrence of WSB. Allelopathic effects of organic acids in the cultivated-layer soil, including the promotion on pathogen growth and inhibition on physiological activity and growth of wheat roots, may be one of the main reasons for the serious occurrence of WSB in the straw returning region in northern China.

Key words: straw returning, wheat sheath blight, Rhizoctonia cerealis, GC-MS, allelopathy, organic acid