Life History of Thrips hawaiiensis (Morgan) Reared on Flower of “Saba” Banana (Musa acuminata x balbisiana Colla)

Abstract

Thrips hawaiiensis (Morgan) is a pest of banana, mango, and pomelo. The study aimed to determine the development and reproductive capacity of thrips under laboratory condition. To start the culture, female thrips were collected from Beltran “Saba” banana plantation in Tuao, Cagayan, Philippines. Thrips were reared on fresh banana flowers in glass containers covered with cotton gauze pad sealed with rubber bands at temperatures of 25 ± 1.0 to 32 ± 2.0 °C, relative humidity of 78–99%, and photoperiod of 12:12 h (L:D). Forty (40) eggs laid within 8 h by first-generation female were observed from 05 Oct–16 Nov 2020. Three (7.5%) males and 37 (92.5%) females emerged from unfertilized eggs. Male average egg incubation, first instar, and second instar larval, prepupal, and pupal days were 1.33 ± 0.47, 1.33 ± 0.47, 1.33 ± 0.47, 1.00 ± 0.00, and 1.33 ± 0.47, respectively. Male average total development period and lifespan were 8.67 ± 0.62 and 9.33 ± 0.94, respectively. Female average egg incubation, first instar larva, second instar larva, prepupa, and pupal periods were 1.24 ± 0.43, 1.24 ± 0.43, 2.38 ± 0.48, 0.59 ± 0.20, and 2.38 ± 0.48, respectively. Female average total development period from egg to adult emergence and lifespan from egg to post oviposition until the adults are dead were 8.89 ± 0.52 and 23.19 ± 7.07, respectively. Female average pre-oviposition, oviposition, and post-oviposition periods were 1.05 ± 0.38, 12.27 ± 6.69, and 0.95 ± 1.20, respectively. The average number of eggs laid by each female was 196.92 ± 75.70. Female second instar larva and pupa development period were longer – which could be due to the bigger body size – and the average lifespan was twice as long as that of male. T. hawaiiensis is a short-lived, asexual insect with high fecundity; based on the life span of female thrips studied, between 7–8 thrips generations could be developed annually.