Molecular identification, occurrence and distribution of Thrips palmi, Frankliniella intonsa and Frankliniella cephalica (Thysanoptera: Thripidae) on cucurbit crops in Panama

Abstract

The main open-field producer regions of cucurbits (watermelon, squash, melon and cucumber) in Panama (Los Santos, Herrera and Coclé provinces) were surveyed for molecular identification, occurrence and distribution of Thrips palmi (the most important pest thrip species on cucurbits in Panama), Frankliniella intonsa and Frankliniella cephalica during the growing seasons of 2009 to 2013 and 2017 to 2018. Forty plots were surveyed and DNA extracts of 186 thrips (larvae and adults) were analyzed by multiplex PCR, using a set of T. palmi-specific primers in combination with a set of insect-universal primers. DNA extracts corresponding to 174 individual thrips (93.5%) rendered both PCR products of expected size with T. palmi-specific and insect-universal primers, whereas the remaining DNA extracts corresponding to 12 individual thrips (6.5%) only rendered the product of the expected size with insect-universal primers. Sequencing of those PCR products and BLAST analysis allowed for the identification of F. intonsa and F. cephalica. Thrips palmi was detected in all three provinces, while F. intonsa and F. cephalica were detected in Herrera and Los Santos provinces. To our knowledge, this is not only the first detection of F. intonsa in Panama, but also the first detection of F. cephalica in Panamanian cucurbit crops.

Keywords

• cucurbits
• molecular identification
• thrips