Laboratory rearing of tea mosquito bug, Helopeltis theivora Waterhouse (Hemiptera: Miridae) on cocoa (Theobroma cacao L.)

Abstract

Tea mosquito bug (TMB), Helopeltis theivora is a most serious pest on cocoa worldwide that inflicts huge economic losses under epidemic situations. Laboratory colonies are necessary to perform year-round research to develop suitable management strategies for this pest. This study aimed to establish a population of TMB on suitable cocoa-feeding substrates under laboratory conditions. We used green cocoa pods and tender shoots as a food substrate and compared the biological parameters of H. theivora between them. The adult females preferred to lay more eggs on pods (32.20 ± 1.86 eggs/female) either singly or in a small group, and low fecundity was observed on shoots (20.75 ± 1.16 eggs/female). Meanwhile, egg hatching was highest on pods (92.48 ± 2.91%) than on shoots (74.08 ± 3.73%). This pest consists of five nymphal instars and the total nymphal duration was 13.53 ± 1.26 and 14.73 ± 0.85 days on pods and shoots, respectively. In addition, the per cent survival of H. theivora was highest on pods (78.66 ± 3.46) and lowest on shoots (51.85 ± 2.33). Significant differences were recorded in adult longevity and the mean life span of males and females were 13.17 ± 1.58 and 16.63 ± 1.64 days on pods; 11.10 ± 1.41 and 14.36 ± 1.53 days on shoots, respectively. Further, females lived longer than males in both substrates. Although, TMB will survive both on pods and tender shoots; rearing on pods could be more suitable and reliable to establish a sizable population of H. theivora under laboratory conditions.