Physical Barriers in the Control of Sagalassa valida in Interspecific Oil Palm Hybrids

Abstract

Sagalassa valida is a pest that restricts the oil palm root system growth, causing damage that reaches as much as 80% of it, consequently reducing the oil palm yield between 50% and 83%, depending on how the plant is managed. The present study aimed to evaluate the influence of physical barriers (mulching) using different parts of oil palm plants on controlling root borer (S. valida) in the interspecific oil palm hybrid OxG. The study was conducted at the Palesema plantation, situated in Mataje Parish, San Lorenzo Canton, Esmeraldas Province, Ecuador, located at 1°17’18” N and 78°50’13” E and 100 m above sea level. 10-year plants from the OxG Coari x La Mé hybrid were used in the study. Parts of oil palm were used as mulching (physical barriers) under the crown of the plant as follows: 200 kg of fruitless bunches, 160 kg of palm fiber, 20 kg of around weeds, 40 kg of pruned palm leaves, also, there was a treatment with insecticide, applying 150 ml of thiamethoxam+lambda-cyhalothrin (in 200 L in water), and one control treatment, without mulching or insecticide (clean area). A completely randomized block design was used. Our results showed that the number of S. valida larvae, the percentage of fresh damaged roots, and leaf emission were assessed. There were fewer S. valida larvae and damaged roots in the treatments with fruitless bunches and fiber at 180 days and with leaves at 90 days after beginning the treatments, while in absolute control, the larval population rose over time. The application of physical barriers reduced the incidence of root borer attacks by 40% compared to areas where these measures were not implemented. The pruned leaves placed on the plate proved to be a suitable alternative for pest control and showed one of the lowest application costs, that make it the best alternative for the integrated management of Sagalassa valida