Population Parameters of Haplaxius crudus (Hemiptera: Cixiidae) under Semi-Controlled Conditions.

Abstract

The palm leafhopper, Haplaxius crudus, is a possible vector of the pathogen that causes the Lethal Wilt of oil palms in Colombia. This disease represents the biggest phytosanitary problem in the eastern palm zone. From 2010 to 2021, more than 7700 ha have been eradicated, with economic losses exceeding 154 million USD. Therefore, knowing the biology of this insect and its population parameters is necessary for developing population control tools. To evaluate these parameters, a cohort of 100 eggs obtained from H. crudus adults from the breeding unit established in the Campo Experimental Palmar de las Corocoras de Cenipalma in Paratebueno, Cundinamarca, was monitored to record the life cycle and the population parameters using a life table under semi-controlled conditions in an oil palm plantation. The life cycle from egg to adult was 62.7 ± 15.5 days (26.1 ± 2.9 °C; HR: 89.8 ± 14.0%). The egg stage lasted 14.6 ± 0.6 days, the nymphal stage 48.1 ± 2.8 days through five instars, and the adult longevity was 14.8 ± 8.4 days. The specific mortality rate (qx) calculated in the life table was 0.14 (for the egg stage), 0.05 (for I instar), 0.05 (for II instar), 0.03 (for III instar), 0.04 (for IV instar), and 0.07 (for V instar). The population parameters' values were as follows: net reproductive rate Ro = 10.96; generation time T = 62.3 days, intrinsic natural growth rate rm = 0.03, and finite growth rate λ = 1.03. These results help us to understand the population dynamics of this insect in the field and for the development of population control studies.