Occurrence of Anastrepha fraterculus (Diptera: Tephritidae) on raspberry and blackberry fruit cultivated in a semiarid temperate highland valley of Tucuman, Argentina

NATALIA MENEGUZZI; LORENA ESCOBAR; CLAUDIA FUNES; SERGIO OVRUSKI; DANIEL KIRSCHBAUM

CABA

Simposio; 9th Meeting of the Tephritid Workers of the Western Hemisphere; 2016

SENASA - IAEA

The aim of this study was to determine the occurrence of A. fraterculus (Af) and C. capitata (Cc) in organic Rubus crops grown in different environments of Tucumán (Argentina), a major fresh fruit exporting province. During two production seasons, 2013 and 2014, ripe fruit from plants of three blackberry (Rubus fruticosus) cultivars (878, Navaho and Tupy) were collected from an organic orchard located in Monte Grande (MG) (27°00′S, 65°24′W, 350 m altitude; humid and perhumid piedmont physiographic region). Besides, in 2016, ripe fruit samples of the blackberry cultivar 878, and the raspberry (Rubus idaeus) cultivar Heritage, were collected from an organic farm in Tafí del Valle (TV) (26°52′S, 65°41′W, 1900 m altitude; basins and intermontane valleys physiographic region). In the MG area berries are harvested in spring (Nov-Dec) while in TV they are harvested in summer (Jan-Mar). Hence, sampling dates in MG were: Nov-6, Nov-14, Nov-20, Dec-5 and Dec-13 (2013); Nov-7, Nov-12 and Nov-19 (2014); and in TV: Feb 5, Feb 19, Feb 24, Mar 10 and Mar 23 (2016). Each fruit sample was placed individually into clamshells and taken to the laboratory, divided into 2 replicates of 20-30 fruits each, placed into clamshells (20×30 cm) with sand at the bottom for larvae pupation. Tephritid adults from each clamshell were recovered weekly, identified and counted. Both Af and Cc were found infesting blackberries in MG, and only Af was found infesting blackberries and raspberries in TV. Fruit fly infestation levels in blackberries were very low in MG whereas in TV they were relatively high, probably due to a more extensive harvest season in TV and/or an environmental effect on fruit fly populations. During the two years of study in Monte Grande, fruit flies were never recovered from fruit samples of the Navajo cultivar. In 2014, tephritids appeared more than a month earlier than in 2013, probably because of the advancement of spring rains in the humid piedmont region. Anastrepha fraterculus showed a remarkable preference for raspberries over blackberries. This is the first record of tephritid fruit fly occurrence in Rubus in northwestern Argentina.