Management of Fusarium Crown and Root Rot of tomato by Solanum linnaeanum L. extracts

Leaf, stem and fruit aqueous extracts of Solanum linnaeanum were tested for their ability to suppress Fusarium Crown and Root Rot (FCRR) in tomato caused by Fusarium oxysporum f. sp. radicis-lycopersici (FORL) and to enhance tomato growth. Leaf extract used at 30% (w/v) was the most effective in reducing disease severity by 92.3% and the extent of vascular browning by 97.56% compared to FORL-inoculated and untreated control. A significant enhancement of growth parameters was recorded on tomato cv. Rio Grande seedlings inoculated with or without FORL. A significant improvement of seed germination was noted. FORL mycelial growth, assessed using the poisoned food technique, varied depending on plant organs, extracts, and concentrations used. Butanolic extracts were the most active, leading to 60.81% decrease in FORL mycelial growth. The high performance liquid chromatography (HPLC) analysis of butanolic extract revealed the presence of thirteen phenolic compounds including seven acids such as protocatechuic acid, salicylic acid, syringic acid, 3.4-dimethoxybenzoic acid, two stilbenes (resveratrol and isorhamnetin 3 O rutinoside) and four flavonoids such as catechol, epigallocatechine, rutin and rutin trihydrate which was the major compound (15.82%). Thus, S. linnaeanum can be explored as a potential source of antifungal and bio-fertilizing compounds.