Untitled

Abstract

Tomato (Lycopersicon esculentum) is one of the world's cash crops particularly in Cameroon. However, in Cameroon, yield declines are caused by the attack of Fusarium oxysporum f. sp. lycopersici. In this study, four essential oil extracts including Cupressus sempervirens, Chenopodium ambrosioides, Azadirachta indica and Capsicum annuum leaves were evaluated for their supression ability on this pathogen, under in vitro and in vivo conditions. In vitro tests of the antifungal activity of essential oils at different concentrations showed inhibition effects on the growth of F. oxysporum f. sp. lycopersici in different rates. The essential oils of C. sempervirens and C. ambrosioides were the most effective at the concentration of 20 μL/mL whereas A. indica was also effective only at the concentration of 100 μL/mL. The most in vitro effective essential oils (C. sempervirens, C. ambrosioides and A. indica oil) were then included in an in vivo assay to evaluate their suppression activities on the pathogen growth on tomato seedlings. The esseantial oils were applied to tomato seedlings as two groups; i) preventively; ii) curatively. The preventively treated plants showed an influence of the essential oils on the slowing of the development of disease with a rate of reduced desease leaves and the stem growth, in comparison to the control plants. In the curatively treated group of plants, there was almost an ineffective action of essential oils on both stem growth and disease progression. Consequently, the essential oil obtained from C. ambrosioides was most effective in vivo at a low concentration (20 μL/mL) against F. oxysporum. f. sp. lycopersici.

Synergistic interplay between arbuscular mycorrhizal fungi and fern manure compost tea suppresses common tomato phytopathogens and pest attacks on-farm

“…These novel techniques should inter alia improve soil health accompanied by an increase of plant resistance against diseases, thereby diminishing the reliance on pesticides and maintaining high agricultural productivity. So far, most studies related to the impact of AMF inoculants have broadly addressed either individual effects or synergistic effects with other microbial inoculants (i.e., of bacterial origin) on plant disease resistance against various pathogens (Nwaga et al, 2010;Simo et al, 2019). In comparison, this study investigated the synergistic effects of inoculating tomato seedlings with an AMF consortium coupled with a biopesticide based on FM compost tea on common tomato plant diseases and pests.…”

“…The global production of tomatoes remains below consumer demand due to several abiotic and biotic adverse factors (FAOSTAT, 2017). Diseases and pests can be major biotic factors that affect the quality and size of the fruit (Blancard et al, 2009;Simo et al, 2019). Abiotic factors such as unfavorable weather conditions, poor crop management, and poor soil quality can also influence tomato growth and yield (Bationo et al, 2006;Rocha, 2009).…”

“…Biopesticides can be generally classified into three categories based on their origin; either they derive from living organisms such as microorganisms or they derive from organic plant and animal products such as green manure, compost, or farmyard manure (Thakore, 2006;Chandler et al, 2011;Leng et al, 2011). Plant-derived substances, such as essential oils and compost tea, have been demonstrated to have multifaceted biopesticidal properties with notable effectiveness in pathogen and pest suppression (Konéet al, 2010;On et al, 2015;Campanelli et al, 2018;Simo et al, 2019). Previous studies have highlighted the insecticidal, insect repellent, and acaricidal potentials of plant-derived oils on vegetable crops (Camara, 2009;Mostafa et al, 2014;Kanko et al, 2017;Asmae et al, 2018;Simo et al, 2019).…”

“…Plant-derived substances, such as essential oils and compost tea, have been demonstrated to have multifaceted biopesticidal properties with notable effectiveness in pathogen and pest suppression (Konéet al, 2010;On et al, 2015;Campanelli et al, 2018;Simo et al, 2019). Previous studies have highlighted the insecticidal, insect repellent, and acaricidal potentials of plant-derived oils on vegetable crops (Camara, 2009;Mostafa et al, 2014;Kanko et al, 2017;Asmae et al, 2018;Simo et al, 2019). Fermented plant extracts, also called compost tea, are plant-based preparations to treat plant pests and diseases or to increase the plant resistance against predators by stimulating their defense system (Deravel et al, 2014).…”