Cumulative oxygen consumption during development of two postharvest insect pests: Callosobruchus maculatus Fabricius and Plodia interpunctella Hübner

Abstract

Insect pests such as Callosobruchus maculatus Fabricius and Plodia interpunctella Hübner cause substantial losses to grain during postharvest storage. In the last few years, hermetic storage technologies have been successfully used by smallholder farmers in Africa and Asia to protect their harvested grain against insect pests. Hermetic technologies owe much of their effectiveness to restricting oxygen availability to insects confined in the containers. There is a need to better understand the biology of specific storage insect pests and their responses to hypoxia. We employed a novel and non-invasive analytical technology, the OxySense 5250i, to measure oxygen levels in closed containers, and evaluated its effectiveness in measuring the total oxygen consumption of two insect pests during their development: C. maculatus and P. interpunctella. The total amount of oxygen consumed by C. maculatus during its larval development period determined with the OxySense apparatus was not different from that previously recorded using another instrument, the Mocon Pac Check 325 gas analyzer. Using the OxySense 5250i, we found that P. interpunctella consumes nearly three times as much oxygen per insect over its larval-to-adult developmental period compared to C. maculatus. Information on the lifetime oxygen consumption of insects provides relevant information to the effectiveness and ability of hermetic technologies to protect stored products against insect pests.

Oxygen Consumption and Acoustic Activity of Adult Callosobruchus maculatus (F.) (Coleoptera: Chrysomelidae: Bruchinae) during Hermetic Storage

“…Other studies have assessed the individual insect consumption rates at normoxic conditions and found that approximately 8 mL O 2 is needed during the lifetime of C. maculatus adults (egg to adult emergence) [ 14 , 42 , 43 ]. Our findings focused on adult stages under hypoxic conditions which prompted the insects to reduce their metabolic activities.…”

Survival of Plodia interpunctella (Hübner) larvae treated with 98% N2 and the life history of their next generation

“…Even though survivors can continue their development and reproduction after a sublethal exposure, our study found that they performed poorly as a function of either delayed development, increased mortality, or reduced oviposition. The average life cycle of P. interpunctella (from egg to adult emergence) at 25°C and 40% RH was 7 days under hermetic condition (Quellhorst et al ., 2018). The pupation rate and emergence rate of the P. interpunctella larvae (20 days after egg hatching) in 5% O 2 were 85 and 11%, respectively, while they were 100% in the control.…”

Effects of environmental factors and storage periods on sesame seed quality and longevity

“…This bag is a common packaging material for sesame staying stored for about a year in Ethiopia and Sudan. On the other hand, (Odjo et al 2020;Ndegwa et al 2016;Quellhorst et al 2018;Tefera et al 2011) reported that hermetic technologies like Perdue Improved Crop Storage (PICS) bags are crucial in reducing postharvest losses in many crops. The PICS bag is relatively better than polypropylene (pp) bags, sisal sacks and polyethylene lined polypropylene bags for sesame storage with germination rate of 93% after stored for 12 months (HuARC 2019).…”