Influence of Sunlight Incidence and Fruit Chemical Features on Oviposition Site Selection in Mango by Anastrepha obliqua: Implications for Management

Abstract

With the aim of identifying key factors that determine oviposition decisions by Anastrepha obliqua for management purposes, we conducted a behavioral study under natural/semi-natural field conditions to identify where exactly in the fruit (upper, middle, or lower sections) females preferred to lay eggs in a highly susceptible mango cultivar (“Criollo”), and whether sunlight incidence and fruit chemical compounds influenced oviposition site selection by this pestiferous fly. Females oviposited in shaded, upper fruit sections where pulp had higher total carbohydrate concentrations but similar total protein, lipid, and polyphenol concentrations than non-oviposited sections. Peel had higher overall nutrient and mangiferin/quercetin-3-D-galactoside (polyphenols) concentrations. An untargeted metabolomic analysis of oviposited and non-oviposited fruit sections identified abscisic acid (ABA) and dihydrophaseic acid glucoside, a by-product of ABA catabolism, as potential chemical markers that could play a role in fruit acceptance behaviors by female flies. We conclude that females preferentially oviposit in fruit sections with optimal chemical and environmental conditions for larval development: more carbohydrates and antioxidants such as mangiferin and ferulic acid and lesser sunlight exposure to avoid lethal egg/larval desiccation/overheating. We make specific recommendations for A. obliqua management based on female host selection behavior, a tree pruning scheme exposing fruit to direct sunlight, application of a host marking pheromone, and the use of egg sinks in the orchard.

Coping with global warming: Adult thermal thresholds in four pestiferous Anastrepha species determined under experimental laboratory conditions and development/survival times of immatures and adults under natural field conditions

“…The air temperature, the size of the fruit and its location on the tree or the ground influence the internal temperature of the fruit and the survival of immature stages ( Sivinski et al, 2007 ). Eggs cannot avoid high and mortal temperatures inside some fruit, but females can diminish the risk of desiccation by avoiding laying eggs in sun-exposed sites on the fruit ( Guillén et al, 2022 ) and larvae can move to fresher areas within the fruit ( Sivinski et al, 2007 ), or as noted before crawl out of the fruit and jump to the ground.…”

Reproductive behavior of fruit flies: courtship, mating, and oviposition

“…Evidently, both the fruit and environmental factors need to be considered when selecting oviposition sites for females. Anastrepha obliqua prefers more nutrients and less light when selecting oviposition sites, 296 whereas B. cacuminata prefers to lay eggs at sites with moderate light intensity, higher heights, and more fruit, and the number of females laying eggs is positively influenced by the temperature and negatively influenced by the relative humidity 297 . In the presence of multiple hosts, A. fraterculus and Ceratitis capitata prefer to lay eggs in oranges and tangerines and dislike lemons 298 .…”

Effect of farmer's behavior in cocoa management on insect diversity in Salayo Cocoa Plantation, West Sumatra, Indonesia

“…Setyawan et al (2020) stated that a higher canopy cover percentage (66.22%) in the mangrove ecosystem results in height insect diversity compared to a lower canopy cover percentage. Guillén et al (2022) found that Anastrepha obliqua females prefer to oviposit in shaded areas with lower temperatures to avoid egg mortality due to desiccation or overheating. Cocoa pruning can positively affect insect diversity if followed by appropriate sanitation measures, namely, leaving one or two litter layers in cocoa plantations.…”