Entomocidal effects of beech apricot, Labramia bojeri, seed extract on a soybean pest, the velvetbean moth, Anticarsia gemmatalis, and its enzymatic activity.

Maria G M Freire,José R P Parra,Roberto T A Júnior,Carlos E G Kubo,Maria L R Macedo,Gary Blomquist

doi:10.1093/jis/14.1.27

Abstract

The effects of the beech apricot, Labramia bojeri A. de Candolle (Sapotales: Sapotaceae), seed aqueous extract on the larval development of the velvetbean moth, Anticarsia gemmatalis Hübner (Lepidoptera: Noctuidae), was evaluated. The extract inhibited larval development, pupal weight, and survival and emergence of adults. Digestive proteolytic activity in larval midgut and feces extracts was determined. Larvae fed 10 g/L of the aqueous extract showed a significant reduction in trypsin activity (~64%), when compared with control larvae. Trypsin and chymotrypsin activities were also detected in fecal material in aqueous-extract-fed larvae, with about ~4.5 times more trypsin activity than the controls. The results from dietary utilization experiments with A. gemmatalis larvae showed a reduction in the efficiency of conversion of ingested food and digested food and an increase in approximate digestibility and metabolic cost. The effect of the extract suggests the potential use of L. bojeri seeds to inhibit the development of A. gemmatalis via oral exposure. The L. bojeri extract can be an alternative to other methods of control.

Highlights

The velvetbean moth, Anticarsia gemmatalis Hübner (Lepidoptera: Noctuidae), is one of the main pests of soybean, Glycine max L. (Merrill) (Fabales: Fabaece), a legume that provides about half the global demand for vegetable oils and proteins
The objective of this study was evaluate the bioefficacy of an aqueous extract of beech apricot, Labramia bojeri A. de Candolle (Sapotales: Sapotaceae), on A. gemmatalis development, nutritional index, digestive proteinase activity, and zymogram analyses of the digestive proteinase activities
There was no difference in the duration of pupation, at 24 hr after pupation, the weight of larvae that were fed on the L. bojeri aqueous extract (LbAE)-containing diet was significantly lower (~ 18 %) than that of larvae fed on the control diet

Summary

Introduction

Materials and MethodsThe velvetbean moth, Anticarsia gemmatalis Hübner (Lepidoptera: Noctuidae), is one of the main pests of soybean, Glycine max L. (Merrill) (Fabales: Fabaece), a legume that provides about half the global demand for vegetable oils and proteins. For the control of pests in storage areas, methyl bromide (MeBr) and phosphine (PH3) are used, but they may cause several problems in stored products (Khani et al 2011). Their widespread use has led to some serious problems, including the development of insect strains resistant to insecticides (Damásio et al 2007; Garriga and Caballero 2011). The objective of this study was evaluate the bioefficacy of an aqueous extract of beech apricot, Labramia bojeri A. de Candolle (Sapotales: Sapotaceae), on A. gemmatalis development, nutritional index, digestive proteinase activity, and zymogram analyses of the digestive proteinase activities. The results of this study suggest that small farmers could collect these seeds, make an aquous extract, and use it for control

Objectives

Results

Conclusion