Field evaluation of the efficacy of neem oil (Azadirachta indica A. Juss) and Beauveria bassiana (Bals.) Vuill. in cotton production

Abstract

Neem oil (Azadirachta indica A. Juss) alone and combined with the entomopathogenic fungus Beauveria bassiana (Balsamo) Vuillemin (isolate Bb11) was applied to control cotton pests. The efficacy of these treatments was compared with that of synthetic insecticides applied either in a calendar-based application or in the 'Lutte Etag ee Cibl ee' (LEC) strategy, consisting of using first calendar-based (half-dose) applications followed by threshold-based treatments. The experiment was carried out in collaborative research with farmers in three cotton agro-ecological zones differing in rainfall, pest prevalence, and farming practices. The neem oil and neem oil-Bb11 treatments required 2 to 6 applications, while conventional and LEC received 6 to 8 applications. The percentage of damaged reproductive organs in plots treated with neem oil and neem oil plus Bb11 was higher than that recorded under the conventional and LEC strategy, with exception of the zone with the highest rainfall; this resulted in yields being 25% and 39% lower, respectively. Yields in the biopesticide plots were 26-42% higher and in the conventional and LEC plots 44-59% higher than those in the control plots that received only water. Overall, the LEC regime scored best, both in yield and profitability. The incidence of natural enemies was highest in the control and in the plots treated with biopesticides. Although the use of entomopathogen Bb11 and neem oil avoids many problems associated with the application of synthetic insecticides, their efficacy needs to be enhanced by improved formulation or by combining them with other pesticides.Evaluating alternatives to conventional cotton pest control C. E. Togb e et al.

Efficacy of neem extracts in the control of tomato insect pest Helicoverpa armigera in Southern Benin

“…Neem oil and K-OPTIMAL allowed obtaining respectively yields gain from 33.8 to 42.39% and 46.16% regarding control. These results confirm Togbé et al [15][16][17] results.…”

“…These results have been demonstrated by some authors like Traoré et al 13 and El Shafiel et Abdelraheem 14 ,. Then, neem oil proved its efficacy in the H. armigera control on tomato increasing the yield.…”

“…But the return to farmers who adopt them could be compensated if the real value of the bio-insecticides on the preservation of the environment was to be estimated, giving farmers a price incentive to grow organic tomato. Yield obtained from organic product (cotton) is far lower than conventional treatments 16 . Without such an incentive, farmers may not be motivated to adopt the bio-insecticides despite their relative advantages for the preservation of the environment compared to conventional tomato.…”

Insecticidal and oviposition deterrent effects of essential oils and their constituents against the invasive pest Drosophila suzukii (Matsumura) (Diptera: Drosophilidae)

“…(Sharaby et al , 2014;van Tol et al, 2007). Neem oil is one of the most commercially recognizable oils that is now widely marketed due to the presence of the insecticidal, antifeedant repellant properties of its active constituent, azadirachtan (Ahmad et al, 2014;Benelli et al, 2014;Sokame et al, 2015;Togbé et al, 2014).…”

Effectiveness of neem seed oil (<i>Azadirachta indica</i> A. Juss: Meliaceae) on <i>Syllepte derogata</i> Fabricius, Lepidoptera: Pyralidae

“…However, cotton is subject to many pest attacks. The incidence of those pests varies from one season to another depending on the prevailing conditions in each growing area (Togbé et al, 2014a). Two categories of pests are dominant on this crop: phyllophagous pests that feed on leaves and carpophagous pests that feed on squares, flowers and bolls.…”