Interactions of Bacillus thuringiensis bioinsecticides and the predatory stink bug Podisus nigrispinus to control Plutella xylostella

Abstract

The diamondback moth (DBM), Plutella xylostella (L.), is a major pest of brassica crops worldwide. Control of this pest is difficult because it rapidly develops resistance to synthetic and biological insecticides and because of the effects of insecticides on its natural enemies. Podisus nigrispinus (Dallas) is a predator that feeds on its prey, as well as on the host plants of its prey, and is an important biological control agent of DBMs. The aim of this study was to determine the susceptibility of P. xylostella larvae to two bioinsecticides: the HD1 strain of Bacillus thuringiensis (B. thuringiensis var. kurstaki) and the commercial product Agree â (B. thuringiensis var. aizawai CG 91). In addition, the impact of these bioinsecticides on the P. nigrispinus consumption of DBM larvae and phytophagy was evaluated. Both the HD1 strain and Agree â caused 100% mortality in P. xylostella larvae.P. nigrispinus nymphs fed only with kale leaves (Brassica oleracea var. acephala) sprayed with water, the HD1 strain, or Agree â did not complete their nymphal development. When prey was also available, P. nigiripinus fed on kale leaves to obtain water. Both nymphs and adults of P. nigrispinus consumed greater numbers of DBM larvae, and fed less on kale leaves, when sprayed with the HD1 strain or Agree â . These results suggest a positive interaction of B. thuringiensis-based products and the predator P. nigrispinus in the control of P. xylostella larvae.

Resistant and susceptible tomato genotypes have direct and indirect effects on Podisus nigrispinus preying on Tuta absoluta larvae

“…Podisus nigrispinus has evolved omnivorous adaptations that allow it to feed on both plant and animal food sources (Torres and Boyd, 2009), similar to other predatory mirids (Biondi et al, 2016). Plant feeding supplies necessary nutrients, steroids (Thummel and Chory, 2002), and water (Magalhães et al, 2015) thereby improving predator development (Oliveira et al, 2002;Evangelista Júnior et al, 2003, 2004. Our results indicate that Santa Clara plants were nutritionally superior to PI 134417 plants in supporting P. nigrispinus nymphal survival and adult longevity.…”

Spodoptera albula susceptibility to Bacillus thuringiensis-based biopesticides

“…The results of our study emphasize the possibility of using Bt-based biopesticides against S. albula; however, the formulation must be carefully chosen. The specificity and selectivity of Bt-based biopesticides are in accordance with integrated pest management procedures (Kogan, 1988) and could even be used alongside other biological control agents (Magalhães et al, 2015;Sanahuja et al, 2011). Fig.…”

Dissecting the Environmental Consequences of Bacillus thuringiensis Application for Natural Ecosystems

“…kurstaki and Bt var. aizawai CG 91, P. nigrispinus demonstrated an increase in predation activity [ 133 ]. Finally, P. nigrispinus demonstrated no preference between intact P. xylostella larvae and those treated with Bt HD1, and consumption of the latter did not affect the biological characteristics of the predator [ 134 ].…”