Molecular Characterization and Assessment of Abundance of Thrips hawaiiensis (Morgan, 1913) on Three Plantations of Cavendish Banana in Davao del Norte, Philippines

Abstract

The study aimed to verify the identity of Thrips hawaiiensis (Morgan, 1913) (Thripidae: Thysanoptera) based on mitochondrial cytochrome C oxidase I marker and determine its seasonal abundance on Gran Naine, Tall Williams, and GCTCV-218 Cavendish banana plantations in Panabo City, B.E. Dujali, and Carmen in Davao del Norte, Philippines. Fifteen (15) flowering/fruiting plants per cultivar per plantation were selected. The survey was conducted on 11–29 Aug 2020, 14–26 Nov 2020, 08–18 Mar 2021, and 11–25 May 2021. Thrips were sampled from bunches consisting of flowers and fruits by the shaking/tapping method. Temperature and rainfall data were obtained from PAGASA. All thrips samples had a significant match with T. hawaiiensis (GenBank KX233567.1) having 100% query cover with 99.39–99.70% nucleotide identity. Female thrips were dominant on all Cavendish cultivars and in the dry season, their counts doubled, whereas male thrips counts increased more than five times. Analysis of variance between the mean numbers of thrips showed no significant difference among cultivars during the dry and wet seasons (p < 0.05). There was a significant difference between mean counts of female and first instar larvae but no significant difference between the mean counts of female, male, and second instar larvae in Panabo City; whereas in B. E. Dujali, and Carmen, there was a significant difference between the mean numbers of female, male, and first and second instar larvae but no significant difference between the mean numbers of male and first and second instar larvae (p < 0.05). Regression analysis showed that thrips abundance was slightly affected positively by maximum average temperature and seemingly not affected by rainfall.