Bioefficacy of Rhynocoris longifrons (Stål) (Heteroptera: Reduviidae) against multiple cotton pests under screen house and field conditions

Abstract

Rhynocoris longifrons (Hemiptera: Reduviidae) is a generalist predator of many cotton insect pests. The hiding behaviour of this predator, which is one of the key factors of predation success, was investigated under screen house conditions. Moreover, we evaluated its biocontrol potential against Aphis gossypii (Hemiptera: Aphididae), Dysdercus cingulatus (Hemiptera: Pyrrhocoridae), Phenacoccus solenopsis (Hemiptera: Pseudococcidae), and Helicoverpa armigera Hübner (Lepidoptera: Noctuidae) under screen house and field conditions. Results showed that R. longifrons life stages preferred to hide under small pebbles in the screen house tests. All the R. longifrons life stages showed a biocontrol potential against the four insect pests under screen house conditions. However, their biocontrol potential had not varied in relation to day and night hours. Augmentative releases of R. longifrons were carried out for two seasons such as Southwest monsoon, 2011 and post-monsoon, 2012. The augmentative release of R. longifrons reduced significantly insect pests on cotton. In fact, the release of this predator in cotton fields was capable to reduce the population of H. armigera (50%), P. solenopsis (28%), D. cingulatus (18.8%), and A. gossypii (11.8%) during the rain fed condition (south-west monsoon season). During irrigated condition (post-monsoon season), populations of D. cingulatus were reduced by 26%, than P. solenopsis (20.6%), and A. gossypii (16.8%). Except ants, no negative impact was reported on other natural enemies present in the cotton field. Significantly higher crop yield and cost benefit ratio was observed in the predator release plots indicating that R. longifrons can be used in an integrated pest management program for multiple cotton pests. Cotton (Gossypium hirsutum L., Malvaceae), is an important cash crop throughout the world. However, its production is severely hampered by several abiotic and biotic factors, such as insect attacks that lead to significant yield reduction. Aphis gossypii Glover (Hemiptera: Aphididae) 1 , Dysdercus cingulatus (Fab.) (Hemiptera: Pyrrhocoridae) 2 , Phenacoccus solenopsis Tinsley (Hemiptera: Pseudococcidae) 3 , and Helicoverpa armigera Hübner (Lepidoptera: Noctuidae) 4 are considered as economically important pests of cotton. Conventional synthetic chemical insecticides are typically extensively used causing significant side effects including pesticide resistance 5 as well as having many ecological and biological impacts 6. Members of Reduviidae are abundant predators of many economically important insect pests 7-9. Reduviids are common in cotton agro-ecosystems 10,11. However, they often fail to colonize fields to provide effective control of the pests. In such a situation, augmentative biological control can be an important approach to protect the cotton. Augmentative biological control is practiced worldwide with more than 150 species of natural enemies now commercially available 12. However, generalist predators, particularly predatory bugs, have been largely ignored for a...

Abundance, diversity and richness of natural enemies of the fall armyworm, Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae), in Zambia

“…The collected species are polyphagous as they prey on several other orders of insect species, including lepidopterans, as reported by Sahayaraj et al. (2020) ( 55 ).…”

Biology, ecology, and management of cotton mealybug Phenacoccus solenopsisTinsley (Hemiptera: Pseudococcidae)

“…162 Augmentative releases of R. longifrons reduced the P. solenopsis population by 28% and 26% under rain-fed and irrigated conditions, respectively. 163…”

Essential elements of biology, mating behavior, and reproduction of Zelus pedestris Fabricius, 1803 (Hemiptera: Reduviidae) fed on Drosophila melanogaster Meigen, 1830 (Diptera: Drosophilidae)

“…Rhynocoris marginatus Fabricius, 1794 (Hemiptera: Reduviidae), is another example of a generalist predator, noted for effectively controlling around 20 species of agricultural pests [13] . A species within this category is Rhynocoris longifrons Stål, 1874 (Hemiptera: Reduviidae), which is also characterized as a generalist predator for various cotton pests [14] . The practical use of predators in biological control methods requires prior studies involving biological, reproductive, and behavioral characteristics [15] .…”