Bioactivity of a water extract of boldus (Peumus boldus Molina) against Spodoptera frugiperda (J.E. Smith) and Helicoverpa zea Boddie (Lepidoptera: Noctuidae)

Abstract

The insecticidal properties of water-extract of Peumus boldus Molina and its effect on the development cycle and feeding habits of Spodoptera frugiperda J.E. Smith and Helicoverpa zea Boddie were evaluated under laboratory conditions in concentrations of 0.25, 0.5, 1.0, 2.0, 4.0, and 8.0% (w/w). Spodoptera frugiperda was the most susceptible with 75% mortality at 7 d at 8% P. boldus concentration, while H. zea had only 30% mortality. LC50 was 2.31 mL kg -1 for S. frugiperda and 16.05 mL kg -1 for H. zea. When the extract concentration increased in the diet, larval size and weight, percentage of pupation and number of adults decreased, and the time required to reach those states was greater. Neonate larvae fed primarily on the diet with the lower extract concentration and the control was preferred by more than 50% of larvae. Inhibition of feeding, growth, weight gain of 3rd instar larvae as well as new biomass production decreased with concentration of the extract.

EXTRACTS OF Schinus molle AND Artemisia absinthium AGAINST Helicoverpa zea ON FRESH EAR CORN IN ECUADOR

“…Only 20 and 28% cumulative mortality occurred with S. molle 100 and 50%, respectively, while rates of 24 and 40% were recorded at 15 DAA with A. absinthium 100 and 50% mortality, respectively. A low mortality rate was also reported by Silva et al (2013), who obtained 30% mortality with the highest concentration (8% w/v) of water extract from P. boldus leaves against H. zea in laboratory tests.…”

“…Major oil components of S. molle dried leaves by hydrodistillation were 27.1% cubenol, 15.3% caryophyllene oxide, and 12.4% spathulenol (Dos Santos et al, 2015). The antifeeding effect of the S. molle extract at both concentrations on 3 rd stadium H. zea larvae was quantitatively similar to that of Silva et al (2013) on the antifeeding effect of P. boldus leaf extracts on 3 rd stadium H. zea larvae. With P. boldus leaf extracts at 0.50 to 8% w/p, the antifeeding effect varied from 37.7 to 57.3%, with no significant differences between the concentrations.…”

“…The specific insecticidal effect on different Noctuidae pest species must be also considered. For example, Silva et al (2013) found 75% mortality with the 8% w/v concentration of the P. boldus extract on 3 rd stadium S. frugiperda larvae, while the same concentration caused only 30% mortality on H. zea larvae of the same age.…”

“…The water extracts of S. molle and A. absinthium caused a gradual increase of the cumulative mortality during 15 d. The effectiveness of these extracts should be complemented with studies of their effect on the entire lifecycle of H. zea. According to Silva et al (2013), when the larvae were treated with the water extract of P. boldus, the size, diameter, weight, and the number of larvae that reached the pupal stage decreased with the increase in concentration of the extract. Besides, these larvae took longer to start pupating.…”

Opportunities and Scope for Botanical Extracts and Products for the Management of Fall Armyworm (Spodoptera frugiperda) for Smallholders in Africa

“…A study under laboratory conditions and conducted on the biological activity of boldus (Peumus boldus Molina) water extract against FAW and Helicoverpa zea (Boddie) (Lepidoptera: Noctuidae) [76] showed that FAW was the most susceptible with 75% mortality at seven days when exposed to 8% w/w of P. boldus extract and had an LC 50 value of 2.31 mL kg −1 . Again, no chemistry was undertaken making the usefulness of this data questionable.…”