Preferences of the codling moth (Cydia pomonella L.) through phenological stages of quince (Cydonia oblonga MILL.) cultivars

MARÍA PÍA GÓMEZ; FLAVIA JOFRÉ BARUD,; ANA CORTEZ-VEGA ; MARÍA LIZA LÓPEZ

Congreso; THE 6th CONGRESS OF THE LATIN AMERICAN ASSOCIATION CHEMICAL ECOLOGY -; 2021

Resumen:Codling moth (Cydia pomonella L.) (Lepidoptera: Tortricidae) is the major world pest of pome fruits. Quince (Cydonia oblonga Mill.) is the most important pome culture in San Juan province, Argentina. The oviposition by females and the choice of neonate larvae are key behaviors for the success of the species. These behaviors can be different between phenologycal stages and cultivars. Through laboratory bioassays we studied the preference of gravid females and neonate larvae of codling moth, using dual-choice bioassays. This was assessed at four different phenologycal stages throughout the quince season. Four quince cultivars (Champion, INTA 37, INTA 117 and INTA 147) were compared by pairs, each pair was considered a combination. Time and final choice of neonate larvae were recorded (season 2019-2020). For oviposition preferences, the number of eggs layed on fruits and on adaxial and abaxial surface of the leaves, was recorded (season 2020-2021). For neonate larvae bioassay, significant differences were observed between phenologycal stages and among cultivars at development stage. INTA cultivars had the highest frequency of choice for larvae. Larvae preferred to reach the fruits, but a high frequency of wandering was observed. Significant differences were observed between phenologycal stages in oviposition bioassays mainly at ripening stage along with a higher number eggs on INTA 147 cultivar. The total number of eggs increased since post-fruit set, being higher at growth and then declining at ripening stage. In all cultivars the oviposition preference was observed for the adaxial surface of the leaves. At ripening, a low number of eggs was observed in areas where fruit pubescence had been lost. Quince cultivars preferences of gravid females and choices of neonate larvae throughout quince season, along with preferred places for oviposition, are relevant to pest management and the chemical ecology of codling moth.