Trichoderma viride induces phenolics in groundnut (Arachis hypogaea L.) seedlings challenged with rot pathogen (Aspergillus niger Van Tieghem)

• Published in: Phytoparasitica 2014-12, Vol.42 (5), p.703-712
• Main Authors: Gajera, H. P., Jadav, J. K., Patel, S. V., Golakiya, B. A.
• Format: Article
• Language: English
• Subjects: Agriculture; Arachis hypogaea; Aspergillus niger; Biomedical and Life Sciences; Ecology; Life Sciences; Liquid chromatography; Nuts; Pathogens; Phenols; Plant Pathology; Plant Sciences; Seedlings; Trichoderma viride
• ISSN: 0334-2123; 1876-7184
• DOI: 10.1007/s12600-014-0413-6

The study showed significant differences in percent collar rot disease incidence in groundnut varieties grown in non-infested soil (T 1 ), challenged with pathogen – Aspergillus niger (T 2 ), and pathogen + Trichoderma viride 60 (T 3 ) treatments. Total phenols revealed a significantly higher content in tolerant varieties (J-11, GG-2) of groundnut compared with moderately susceptible (GAUG-10, GG-13) and susceptible (GG-20) varieties. The phenol content accumulated at a higher rate (193%) in GG-20, followed by GG-2 (146%) and J-11 (107%) varieties during disease development stages. HPLC analysis detected six major phenolics, viz., hydroquinone, gallic, chlorogenic, ferulic, salicylic and cinnamic acids. Among six peaks, hydroquinone was found highest in GG-2 at 3 days in T 3 . Gallic and salicylic acids increased up to 9 days, while ferulic acid continued to induce up to 15 days in tolerant varieties (J-11, GG-2) of Trichoderma- treated (T 3 ) seedlings. A correlation study indicated that Trichoderma treatment induced five phenolics – except gallic acid – with a higher level of significance in a susceptible variety to reduce disease incidence compared with tolerant varieties. Results demonstrate the T. viride 60 mediated systemic induction of phenolics for biologic control and their probable role in protecting groundnut against A. niger infection.