Benzothiadiazole- or methyl jasmonate-induced resistance to Colletotrichum musae in harvested banana fruit is related to elevated defense enzyme activities

• Published in: The journal of horticultural science & biotechnology 2007, Vol.82 (4), p.500-506
• Main Authors: Zhu, Shijiang, Ma, Baocheng
• Format: Article
• Language: English
• ISSN: 1462-0316; 2380-4084
• DOI: 10.1080/14620316.2007.11512265

The ability of benzothiadiazole (BTH) or methyl jasmonate (MeJA) to induce disease resistance in harvested banana fruits was investigated in relation to the activities of several defense-related enzymes. Harvested banana fruit were sprayed with BTH or MeJA solution before being stored at 22°C. Disease development and the activities of six defense-related enzymes were monitored during storage. Compared with untreated fruits, BTH or MeJA treatment significantly reduced the severity of disease in non-inoculated bananas, and lesion diameters and the incidence of disease in bananas inoculated with Colletotrichum musae. The activities of the defense-related enzymes peroxidase (POD), catalase (CAT), polyphenol oxidase (PPO), phenylalanine ammonia lyase (PAL), β1,3-glucanase, and chitinase were all enhanced in BTH- and in MeJA-treated banana fruit whether inoculated with the pathogen or not. The results suggest that post-harvest decay in bananas can be controlled by BTH or MeJA, and involves activation of the disease defense system. In non-inoculated bananas, MeJA and BTH had similar effects on the three defense enzymes (CAT, PPO and PAL), but different effects on the three PR proteins (POD, β1,3-glucanase and chitinase). In inoculated bananas, MeJA and BTH had similar effects on all six enzymes.