Evaluación de daños causados por plagas que atacan la mazorca en algunos genotipos de cacao bajo condiciones de campo en Lodana, Manabí

Abstract

Cacao, Theobroma cacao L., is native to the Ecuadorian Amazon, and therefore the implicit genetic diversity can be used for different purposes such as pest management. In Ecuador there are genotypes of national complex cacao, introduced and their crosses. Until now, little has been evaluated about the behavior of these genotypes against pest attacks. This work aimed to evaluate the damage caused by pests that attack the pod in some cocoa genotypes. The study was carried out in a 2800 m2 plot of 4-year-old cacao, located at the La Teodomira experimental campus, Lodana, Manabí. The lot contains 10 caco genotypes, 28 treatments, of which 24 are grafted and four without grafting, arranged in random blocks with three repetitions. Of these, eight grafted treatments (rootstock/graft) were chosen: EET-399/EET-576, EET-399/CCN-51, IMC-67/EET-484, IMC-67/EET-575, EET-400/EETP -800, EET-400/EET-484 and POUND-12/EET-484, POUND-12/CCN-51. During the period June - October 2023, the damage caused to the ears by stink bugs, Monalonion sp., was evaluated. (Hemiptera: Miridae), red-banded thrips, Selenothrips rubrocinthus (Giard) (Thysanoptera: Thripidae) and scale insects, Dysmicoccus sp. (Hemiptera: Pseudococcidae). The ears per tree were separated into three types (small, medium and large) and the total number of ears was counted, as well as those damaged by type, with which the percentage and severity of the damage was calculated. The small ears were less affected by stink bugs, while the large ones had the lowest percentages of damage by thrips and mealybugs. Regarding the damaged ears, the treatments POUND-12/CCN-51, EET-399/CCN-51 and IMC-67/EET-575 exhibited less severity in damage by bedbugs, thrips and mealybugs, respectively. However, no severity was higher than grade 1. This study provides important information about damage to pods caused by some pests.