Feeding preference and reproductive fitness of Rhyzopertha dominica (Fabricius, 1792) in a choice-based feed paradigm

Abstract

Objective: This study is designed to understand the feeding preference of R. dominica, when three grains and their flours are provided in a choice-paradigm, constructed in the form of a poly vinyl chloride tunnel, in which feed materials are made available at random. Methods and Analysis: A total of 200 beetles were released into the choice-paradigm, and the number of beetles in each feed was counted once in every 24 h. When the beetles in the choice chamber were enumerated after 96 h, 26 percent of the released beetles were found in wheat grain; 25% in wheat flour; 12 in rice; 11 in chick pea; 10 in rice and chick pea flours and 6% in the outer tunnel without opting for any feed. On the basis of the feed on which R. dominica were reared, changes were observed in selected key biological characteristics. Findings: The research findings showed that wheat and wheat flour were preferred against rice, chick-pea and their flours. The incubation period increased significantly (51%) when reared in chick pea flour. In beetles reared on this feed, total larval period increased by 39%, pupal period by 31% and total developmental period by 39%. The fecundity decreased by 11%, whereas, male and female longevities respectively by 20% and 24%. Egg hatching was not much affected by the type of feed. Hatchability was 92% for wheat flour and 97% for rice and chick pea grains. Novelty: R. dominica, a primary pest of stored wheat, seemed to possess the evolutionary plasticity to survive in a variety of feed materials when the primary diet is not available.

Distance-based Decision-making in Oviposition byTribolium castaneumHerbst (Coleoptera: Tenebrionidae) on Low- and No-gluten Flours

“…Although time spent in a given flour patch has been shown to be quite short for T. castaneum (Campbell 2002), certain chemical components, such as amino acids, can discourage egg laying (Schoonhoven and Voysest 1991). In addition, folic acid, phosphorus, and protein all greatly impact fecundity of T. castaneum and T. confusum (Fraenkel and Blewett 1947, Chaudhary and Lemonde 1962, Astuti et al 2020, Sheeba and Ramani Bai 2021). In our study, garbanzo, teff, rye, and spelt flours all have higher protein content compared to the other flours surveyed (Gerken and Campbell 2020) and show preference for oviposition in the small arena assay.…”

“…For instance, when exposed to three different diets simultaneously, Tyrophagus putrescentiae (Schrank) (Acari: Acaridae) chose to lay more eggs on mouse food and corn meal, even though their eggs had overall higher fitness success on dry yeast (da Silva et al 2018). When given a choice between wheat and wheat flour against rice, rice flour, chick-pea, and chick-pea flours, Rhyzopertha dominica (F.) (Coleoptera: Bostrichidae) did not choose wheat or wheat flour, even though wheat supported the highest fecundity (Sheeba and Ramani Bai 2021). Callosobruchus maculatus (F.) (Coleoptera: Bruchinae) females, on the other hand, were able to choose the cowpea variety, among three different cowpea varieties, that corresponded to the highest rates of progeny emergence (Kébé et al 2020).…”