[RESEARCH NOTE]

 

Philippine Journal of Science
152 (5): 1595-1598, October 2023
ISSN 0031 – 7683
Date Received: 05 May 2023

 

Influence of Planting Date and Planting Distance
on Population Density of Onion Armyworm

Christine Joy S. Manalili1,4, Jasper Neil R. Mandac1,4, Catherine Joy Garcia1,3,
Paula Blanca G. Aquino1,2, Milagros S. Diaz3,5, John Dave C. Aquino1,2,4,6*,
and Marilyn G. Patricio1,3

1Crops and Resources Research & Development Center, Research, and Extension,
Central Luzon State University, Science City of Muñoz 3120 Nueva Ecija, Philippines
2Department of Biological Sciences, College of Science,
Central Luzon State University, Science City of Muñoz 3120 Nueva Ecija, Philippines
3Department of Crop Protection, College of Agriculture,
Central Luzon State University, Science City of Muñoz 3120 Nueva Ecija, Philippines
4Department of Crop Science, College of Agriculture,
Central Luzon State University, Science City of Muñoz 3120 Nueva Ecija, Philippines
5Department of Extension Education, College of Agriculture,
Central Luzon State University, Science City of Muñoz 3120 Nueva Ecija, Philippines
6Department of Biology, University of Oxford,
South Parks Road, Oxford OX1 3RB United Kingdom

*Corresponding author: jdaveaquino@clsu.edu.ph

[Download]
Manalili CJ et al. 2023. Influence of Planting Date and Planting Distance on
Population Density of Onion Armyworm. Philipp J Sci 152(5): 1595–1598.
https://doi.org/10.56899/152.05.06

 

 

ABSTRACT

Onion is an important crop in the province of Nueva Ecija, Philippines. Currently, its production is being constrained by onion armyworm (OAW; Spodoptera exigua). The impact of planting dates and distance on the infestation of OAW was studied across two productions. The aim is to evaluate the influence of different combinations of planting dates (November, December, and January) and row spacing [5 cm x 10 cm, 8 cm x 10 cm, 10 cm x 10 cm, and farmer’s practice or waray (6–10 cm x 6–10 cm)] on the damage and population density of OAW. The count of observed OAW larvae from the earliest month (November) and during the month of the usual production period (November–December) was negligible to minimal. However, a significant increase in the OAW population during late planting (January). In terms of leaf damage caused by the OAW feeding, November, December, and January planting had an increasing percentage as the OAW population also increased. There was an increase in bulb diameter as the row spacing widens (10 cm x 10 cm), as well as an increase in the number of marketable bulb onions when it is narrow (5 cm x 10 cm). This study showed that planting dates and distances should be one of the major considerations in onion production and insect pest management.