Sporminarin A, a polyketide from Sporormiella isomera as promising tomato seed coating against Botrytis cinerea
摘要
To mimic real-life scenarios in controlling Botrytis cinerea in tomato seedlings, we explored curative and preventive treatment strategies using crude extract from the fungal endophyte Sporormiella isomera. Curative and preventive strategies consisted of (i) seed-bath spores contamination followed by spray-treatment and (ii) seed-bath treatment followed by spray-contamination, respectively. The extract of S. isomera was bioassay-guided fractionated and sporminarin A was identified using comparative analysis of spectrometry and spectroscopy data. The efficacy of this compound and extract against pathogen was assessed in vitro (%I: 82.74 ± 1.66 at 0.005 mg mL⁻¹ and 88.14 ± 4.71 at 0.1 mg mL⁻¹). Germination indices estimated the modulation of the germination process under the effect of crude extract [C = 10 mg mL−1] of contaminated seeds in both strategies. To evaluate and describe the effects on seedling growth and symptoms severity the development and necrosis indices, respectively, were used. The germination parameters revealed that the extract is innocuous to seedlings in both strategies, and the presence of pathogen in the curative strategy accelerates the dynamics of germination. Treatment in curative strategy improved seedlings growth compared to positive control (Index of Development: treated and contaminated seeds = 1.23 versus contaminated seedlings = 0.78, p < 0.05) and reduced symptoms by 19%. Treatment in the preventive strategy reduced symptoms severity by 61% compared to positive control group (p < 0.05). These findings underline the potential use of sporminarin A enriched extract in preventive strategies against harmful effects of B. cinerea.