Growing hot pepper for cabbage looper, Trichopulsia ni (Hübner) and spider mite, Tetranychus urticae (Koch) control

Abstract

With the public perception that synthetic pesticides leave harmful residues in crop produce for human consumption, there has been increased interest in using natural products for pest control. The potential of using fruit extracts of hot pepper for controlling the cabbage looper, Trichopulsia ni (Hübner) and spider mite, Tetranychus urticae Koch is explored in this investigation. Crude extracts from fruits of Capsicum chinense, C. frutescens, C. baccatum, and C. annuum, were prepared and tested under laboratory conditions for their insecticidal and acaricidal performance. Mortality was greatest (94%) when fruit extract of accession PI-593566 (C. annuum) was sprayed on larvae of the cabbage looper, while crude extracts of accessions PI-241675 (C. frutescens) and PI-310488 (C. annuum) were repellent to the spider mite. We investigated differences in chemical composition of the crude fruit extracts that may explain the observed differences in mortality and repellency between accessions. Gas Chromatography-Mass Spectrometry spectrometric analysis revealed that capsaicin and dihydrocapsaicin, the pungent components of pepper fruit, were not correlated with toxicity or repellency, indicating that the two capsaicinoids are not likely related to the efficacy of pepper fruit extracts. Major compounds in hot pepper fruit extracts were detected and identified as pentadecanoic acid methyl ester, hexadecanoic acid methyl ester, and octadecanoic acid methyl ester. Spectrometric analysis and toxicity to cabbage looper larvae revealed that pentadecanoic acid methyl ester is likely related to cabbage looper mortality. However, the concentration of pentadecanoic acid methyl ester in some accessions was insufficient to explain the observed mortality of cabbage looper and repellency of spider mite. Fruit extracts of accessions PI-593566 (C. annuum) and PI-241675 (C. frutescens) could be useful for managing populations of cabbage loopers and spider mites, which could reduce reliance on synthetic pesticides. Further study is needed to investigate performance of hot pepper extracts under ultra-violet light and field conditions.

On-Farm Evaluation of Homemade Pepper Extract in the Management of Pests of Cabbage,Brassica oleraceaeL., and French Beans,Phaseolus vulgarisL., in Two Agro-Ecological Zones in Ghana

“…The way forward is to develop effective alternative options for pest management from plant products that are readily available, cheap and safe to the environment, wildlife and consumers for adoption by the small-scale vegetable growers. Organic farming is increasingly becoming a well embraced nature-friendly and sustainable farming system as opposed to conventional farming which relies heavily on chemical inputs (Antonious et al 2007;Baidoo et al 2012). Organic farming has added advantages such as conserving natural enemies of pests, maintaining ecological balance and the integrity of the crop as well as promoting food and environmental safety Osei et al 2013).…”

“…Organic farming has added advantages such as conserving natural enemies of pests, maintaining ecological balance and the integrity of the crop as well as promoting food and environmental safety Osei et al 2013). Key focus will be the development and promotion of effective pest control products from plant origin Amoabeng et al 2013) and this has recently attracted a lot of attention worldwide (Ascher 1996;Zehnder et al 1997;Obeng-Ofori & Ankrah 2002;Okoth et al 2002;Antonious et al 2007;Davis 2007;Mochiah et al 2011). Despite the benefits of organic farming, among the key challenges is the lack of adequate technologies that are acceptable and can easily be incorporated into organic farming systems ).…”

“…An earlier study in the laboratory concluded that fruit extracts of hot pepper, Capsicum frutescens L. (Solanaceae) were effective in managing the cabbage looper, Trichoplusia ni (Hübner) (Lepidoptera: Noctuidae) and the spider mite, Tetranychus urticae Koch (Antonious et al 2007). Recent on-station studies in Kwadaso, Kumasi, Ghana also revealed that crude water extracts of fruits of hot pepper, C. frutescens (20 g/l w/v) was effective in controlling the pests of cabbage like the semisynthetic insecticide ATTACK ® (emamectin benzoate) and had minimal effect on natural enemies Fening et al 2013).…”

Residue level and dissipation pattern of spiromesifen in cabbage and soil from 2-year field study

“…Cabbage is prone to multiple pests and diseases. Cabbage whitefly, aphids, and mites are considered as destructive pests which reduce the yield significantly (Trdan and Papler 2002;Antonious et al 2007;Alavo and Abagli 2011;Richter and Hirthe 2014). Spiromesifen could be used for control of these pests (Marcic et al 2011).…”

Laboratory Evaluation of Biorational and Low Risk Insecticides and Their Mixtures for Management of Diamondback Moth Larvae

“…The amounts of pepper needed to achieve such high concentrations are not economically feasible for a pesticide product source that will compete as a human food source. Synthetic capsaicin will be a cheaper alternative [23], but this was not tested in this study, thus there is need for caution in concluding that isolated compounds from natural sources are better. For example, azadirachtin from neem does not appear to do well as the whole plant part extract.…”