The Maize Webworm, Cryptoblabes gnidiella, belonging to the Family Pyraustidae of the Order Lepidoptera, also known as the Southern Corn Webworm. It is a polyphagous moth whose larvae feed on the maize plant’s leaves, stems, and ears. The damage caused by the larvae can significantly reduce crop yield and quality. The larvae can also carry fungal and bacterial diseases, affecting the crop’s yield and quality.
The pest can potentially spread diseases, such as the maize streak virus. To effectively manage this pest, it is important to understand its life cycle, its preferred habitats, and the best methods for controlling it. This article will provide an overview and discussion of the Maize Web Worm Pest in Maize crops, including its symptoms, identification techniques, and control.
Maize Web Worm Pest Management
Life Cycle of Maize Web Worm Pest in Maize Crop
- Egg: The female worm lays up to 100 eggs. The eggs are laid on the upper and lower surfaces of the leaves of maize plants.
- Larva: The eggs hatch within five days, and the larvae feed on the underside of the maize leaves.
- Pupa: After about five weeks of feeding, the larvae spin a web and form a pupa. It remains in this form for 1-2 weeks.
- Adult: After 1-2 weeks, the pupa emerges as an adult. The adult moths feed on the pollen and nectar of maize flowers.
The Maize Webworm is a very active pest with a high reproductive rate. It can complete up to 6 generations in a single season, with each generation lasting about 25 days. The larvae are particularly active at night and can cause extensive damage in a very short period.
Occurrence of Maize Web Worm Pest in Maize Crop
- Location of maize web worm pest: This pest is native to Central and South America and is found to infest the maize crops in Africa, Brazil, Argentina, Colombia, Peru, India, Bangladesh, and China.
- Host range: The maize webworm pest can infect different crops, including maize, wheat, sorghum, millet, and rice.
Factors Favoring the Population Increase of Maize Web Worm Pest in Maize Crop
- Climate – High temperatures, high relative humidity, and abundant rainfall provide ideal conditions for this pest’s rapid development and reproduction.
- Food availability – Maize webworm has a wide range of food sources, which helps increase its population. These include weeds, other grasses, and other crop plants.
- Natural enemies – Predators such as birds, reptiles, and other insects can help control the maize webworm population.
- Crop residues – Crop residue left in the field provides an ideal breeding ground for the maize webworm. The presence of crop residue also provides an ideal food source for the pest to feed on.
Identification of Maize Web Worm Pest in Maize Crop
- Egg: The eggs are small, white, and oval-shaped, laid in solitary on the grains and spikelets.
- Larva: The larvae are yellowish-green in color, have a black head, and are 1.2cm long.
- Pupa: The pupae are brownish-gray and are about 5-6 cm long.
- Adult: The adult worm is a dull-gray moth with dark grey forewings and a wingspan of up to 1.75 cm.