An evaluation of the performance of Trichogramma evanescens Westw in the control of corn borer (Ostrinia furnacalis Guenee) on yellow corn (Zea mays Linn)

• Main Author: Cadiz, Rolando D.
• Format: text
• Language: English
• Published: Animo Repository 1996
• Subjects: Corn > Diseases and pests > Control; Trichogramma; Ostrinia; Agricultural pests > Control; Plant diseases; Biology; Education
• Online Access: https://animorepository.dlsu.edu.ph/etd_masteral/1720
• Institution: De La Salle University

An evaluation of the performance of a parasitoid, Trichogramma evanescens in the control of corn borer that damages yellow corn is conducted to assess its value as an effective biological control agent of corn borer. The study was conducted at the Cagayan State University at Carig, Tuguegarao, Cagayan from September to January, 1996. The study was laid out using the crisscross design. It comprised three blocks representing Treatment-1 (T1-insecticides), Treatment-2 (T2-trichocards) and Treatment-3 (T3-control). It was noted that those applied with trichocards produced the highest grain yield per hectare with 4,780.00 kgs.. This was followed closely by the insecticides-treated group -- [Lannate 19EC (methomyl) and Sevin 85WP (carbaryl)], with 4,648 kgs. The control group yielded 3,318 kgs. per hectare.Corn borers constituted the most dominant form of infestation particularly in the control group (T3). Corn borer infestation was clearly manifested by the presence of egg masses under the tender parts of the leaf whorls, presence of holes in horizontal rows through the leaf whorls and the appearance of fecal matter or casting. Plants infested with corn borers had stunted growth as indicated by clumped and broken tassels, broken stalks and entrance holes, and diseased and stunted growth of corn ears. Plants were likewise affected by downy mildew, leaf rust and earworms. Another insect pest whose species cannot be ascertained was also noted. In all the treatments, insect pests particularly corn borer egg masses were observed on plants three weeks after planting.For a more significant reduction of corn borer damage, it is highly recommended that trichocards be applied as early as two weeks post-germination. Detasseling should be practised as soon as they appear considering that they are attractive to corn borer egg laying.