Development and implementation of action thresholds for major rice pests in Zaragosa, Nueva Ecija [Philippines]
1987
Bandong, J.P. | Litsinger, J.A.
The variety in abundance and occurrence of rice pests between fields, seasons, and growth stages made prophylactic control measure counter productive. The number of eggs (0.5-1/hill) for rice whorl maggot, Hydrellia philippina Ferino and the number of larvae (1-2/hill) for defoliators, rice green semi-looper Naranga aenescens Moore, rice hairy caterpillar Rivula atimeta (Swinhoe), rice leaf folders Cnaphalocrocis medinalis (Guenee), and Marasmia patnalis Bradley were more appropriate indicators of action threshold than the usual unit of damaged leaves. Control for stem borer Scirpophaga incertulas was improved using indicator based on egg mass (0.5-1/m square) than on percent deadhearts. The use of effective but selective chemicals was necessary to achieve satisfactory and stable insect control.
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