Insecticidal activity of the extracts of Piper retrofractum fruit and Tephrosia vogelii leaf and their mixtures against Crocidolomia pavonana

Abstract

This laboratory work was carried out to evaluate the insecticidal activity of the extracts of Piper retrofractum (Piperaceae) fruit and Tephrosia vogelii (Fabaceae) leaf and their mixtures against the cabbage head caterpillar, Crocidolomia pavonana. Ground plant materials of the two plant species were extracted separately with n-hexane and methanol. The results of leaf-residue feeding bioassays showed that P. retrofractum (Pr) and T. vogelii (Tv) hexane extracts had strong insecticidal activity against C. pavonana larvae (LC95 < 0.5%) and were more active than their respective methanol extracts. Pr and Tv hexane extract had a moderate and a rather weak contact effect on C. pavonana larvae, respectively. In feeding tests, Pr + Tv (1:1) hexane and methanol extract mixtures indicated synergistic joint effect both at LC50 and LC95 level, whereas in the contact test, the mixture of Pr + Tv (1:1) hexane extract was synergistic at the LC50 level but antagonistic at the LC95 level. In choice tests, antifeedant effects of Pr and Tv hexane extracts at LC25 to LC70 levels on C. pavonana larvae followed a concentration-dependent fashion. Thus, separate or mixed P. retrofractum and T. vogelii extracts are potential alternatives for the control of C. pavonana.

Effectiveness of Cordyceps sp. and Beauveria Bassiana Against Large Cabbage-heart Caterpillar, Crocidolomia Pavonana Fabricius (Lepidoptera: Crambidae)

“…Pests control efforts can be carried out with more environmentally friendly pesticides such as using botanical and microbial insecticides. Most of the studies that have been conducted have tested the effectiveness of botanical insecticides [4,[6][7][8]. Another alternative in controlling insect pests is the use of microbes as pest control agents.…”

Insecticidal activities of long pepper (Piper retrofractum Vahl) fruit extracts against seed beetles (Callosobruchus maculatus Fabricius, Callosobruchus chinensis Linnaeus, and Sitophilus zeamais Motschulsky) and their effects on seed germination

“…These compounds are major constituents of well-known substances including botanical insecticides, deterrents, and repellents that may be useful for controlling a wide range of pests ( Isman, 2006 ). Research has been performed regarding the effectiveness of hexane extract from long pepper fruit in controlling different insect pests such as cabbage head caterpillar larvae ( Prijono et al., 2020 ), tobacco cutworm larvae ( Ratwatthananon et al., 2020 ), and southern house mosquito larvae ( Wiwattanawanichakun et al., 2018 ). These reports also showed that by using hexane solvent, the long pepper fruit extract presented higher effectiveness against insects than other solvents such as dichloromethane, ethyl acetate, methanol, and ethanol.…”