Biocidal capacity of Capsicum annum extracts on Spodoptera exigua (Lepidoptera: Noctuidae) larvae

Abstract

The indiscriminate use of agrochemicals for the control of pest organisms, especially insects, generates problems ranging from resistance to the molecule used, the use of higher doses and/or increased toxicity of the products, increasing the risk to wildlife and people working in the fields, as well as to final consumers. In this research, the biocidal capacity of Capsicum annum extracts on Spodoptera exigua larvae (Lepidoptera: Noctuidae) was determined in relation to the dose used and the mortality obtained as a function of time. By means of the Scoville scale, the hotness index of three chili bell pepper varieties (habanero, cabro and pimentón) was determined. After selecting the habanero variety as the one with the highest degree of hotness based on organoleptic tests, concentrated extracts of pulp, seed and whole fruit (factors) were obtained from which five doses were derived to confirm the lethal concentration 50 (LC50) in Spodoptera exigua larvae. The results are contrasted against a positive and a negative control by means of a randomized block design. The highest mortality was recorded within three hours in the extracts from habanero chili seed with LC50 80 ml L-1 of water. In in vivo tests, no damage to the foliar laminae of the crops where the test was applied was recorded. It is necessary the continuity of the experiment in different stages of development of various crops, as well as the monitoring of the pest organisms able to control.