Startup of Climate-Smart Integrated Pest Management Against Corn Earworm Helicoverpa zea (Boddie) in Maize (Zea mays L.) for Altering Insect Risk

Abstract

Climate and environment changes can cause spreading of harmful insects into new areas and change their seasonal phenology, resulting in faster development and increased food consumption in ecosystem. Basically, corn earworm Helicoverpa zea (Boddie) (Lepidoptera: Noctuidae), is a well-known established global pest of corn (Zea mays L.), and causes leaf injury by feeding in vegetative stage giving ragged appearance, and preferentially forages on silk tissue, ear tip and kernels of plant. An elevated CO₂ can increase levels of simple sugars in leaves and lower their nitrogen content resulting an increase in damage caused by insect to consume more leaves for meet metabolic requirements. Higher temperature from global warming, lowers effectiveness of some pesticides and more number of pest may survive during winter season leading to spread of insect in both hemispheres. The dislodgement of earworm eggs is resulted from plants by the action of rain and wind, and these conditions influence on caterpillars that pupate into soil. Climate-smart pest management options are grow corn early to escape peak egg laying period, develop corn hybrids with silk comprising antibiotic chemical against larvae and having husks tightly fitting around ear, implement pest scouting, use economic threshold level, adopt transgenic corn hybrids, initiate Bacillus thuringiensis Berliner and nucleopolyhedrovirus sprays to target early instars of pest’s population, predators and parasitoids applications, and insecticide usage as last resort. As climate change exacerbates pest problem, future management strategies include monitoring climate and pest populations, modified integrated pest management strategies, and use of modelling prediction tools.