Suppression of Fungal and Bacterial Diseases of Cucumber Plants by Using the Spent Mushroom Substrate of Lyophyllum decastes and Pleurotus eryngii

Abstract

AbstractThe protective effect of autoclaved water extract from spent mushroom substrate (AWESMS) and autoclaved spent mushroom substrate (ASMS) of the edible mushrooms Lyophyllum decastes (hatakeshimeji) and Pleurotus eryngii (eringi) against fungal and bacterial diseases was investigated on cucumber plants. When the plants were treated with AWESMS by spraying the first true leaves and inoculated with the target pathogen 7 days later, AWESMS of hatakeshimeji significantly reduced powdery mildew by Podosphaera xanthii, angular leaf spot by Pseudomonas syringae pv. lachrymans, but not Corynespora leaf spot by Corynespora cassiicola and scab by Cladosporium cucumerinum. When the plants were grown in a mixture (1 : 2, v/v) of ASMS of hatakeshimeji and soil, a significant disease reduction was observed in powdery mildew, scab and angular leaf spot. The protective effect was also observed against anthracnose on plants treated with AWESMS or on plants grown in a mixture of ASMS of eringi (1 : 3, v/v). Our results indicated that AWESMS and ASMS, independently of the mushroom type, provide a protective effect against fungal and bacterial diseases. Therefore, SMS should be considered an easily available source of active compounds to protect plants from fungal and bacteria infections, helping alleviate the waste disposal problem in the mushroom industry and creating an environmentally friendly method to reduce plant pathogens.