Lack of phenotypic variation despite population structure in larval utilization of pea aphids by populations of the lady beetle Hippodamia convergens

Abstract

15The convergent lady beetle (Hippodamia convergens) is a generalist natural enemy that is 16 utilized extensively in augmentative biological control across the United States. Recent studies 17 have pointed to both genetic and phenotypic differences in Western (California) versus Eastern 18 (Kansas) populations of the species. Here we investigate phenotypic differences in their 19 utilization of pea aphids in (a) Eastern versus Western populations, (b) Hybrid Eastern and 20 Western populations versus their progenitor populations, and (c) within population competition 21 rates in Eastern, Western, and Hybrid populations. Across eight replicate treatments, we find no 22 phenotypic differences (P > 0.2), contradicting previous genetic and behavioral studies. Hybrid 23 F1 populations however show an overall greater percentage weight gain, potentially indicative of 24 a hybrid vigor effect, and greater fitness of augmented populations of the species.

Insights from Population Genomics to Enhance and Sustain Biological Control of Insect Pests

“…Estimating inbreeding using genetic data from populations of biological control organisms in conjunction with assays of fecundity, competition and efficiency of feeding on pests can inform success of biological control programs. For example, lab-inbred (Eastern and Western USA) populations compared to outbred (augmented Eastern-Western USA hybrid) populations of H. convergens, lack phenotypic variability despite genetic differences and exhibit equitable success in pea aphid utilization [107]. Tools to estimate inbreeding often use summary statistics such as Identity By Descent (IBD) probabilities, inbreeding coefficients and runs of homozygosity (ROH), often only delimited by the types of genetic data used to compute them.…”

Biology and performance of the predator Hippodamia convergens, reared on cabbage aphids Brevicoryne brassicae, Myzaphis rosarum and Myzus persicae

“…H. convergens es un predador especializado de pulgones (Stowe et al, 2021) conocido como mariquita (Omkar & Pervez, 2016). Tanto en estado adulto y larval es un predador económicamente importante, se alimenta de una variedad de presas (Grenier et al, 2019;Mercer et al, 2020) y también se puede utilizar para controlar plagas en invernadero (Riddick, 2017). En el Perú se encuentra en diversos agro ecosistemas y es de importancia (Bustamante-Navarrete, 2020), se alimenta de varias especies de pulgones (Abbas et al, 2020), mosca blanca, chinches, cochinillas y ácaros de plantas (Mendoza, 2020).…”