LEAST SURFACE COUNTING FOR THRIPS AND W HITEFLIES ON STICKY RAPS ON GREENHOUSE CUCUMBERS
MÍNIMA SUPERFICIE DE RECUENTO EN TRAMPAS ADHESIVAS PARA TRIPS Y MOSQUITAS BLANCAS EN PEPINO DE INVERNADERO
Author
Carrizo, Paola Irene
Abstract
Counting time of insects trapped on sticky traps might be reduced, considering only part of the plates,afler examining their distribution on the surface of the traps. This work examined the possibility forFrankliniella occidentalis and Trialeurodes vaporariorum, two pests of greenhouse cucumbers, in a givenarea of standard 10 x 13 cm sticky traps. Tests were carried out with yellow and blue traps, counting thoseinsects traped on whole traps, and on seven different distribution areas. Frankliniella occidentalis representedmore than 95% of the trips species, and whiteflies were 100% Trialeurodes vaporariorum. The expectedcapture was compared with catches on each design using the G fitness test. For whiteflies, 96% of the testsfitted the expected valúes. For thrips, 32% and 13% did the same for yellow and blue traps, respectively.Paired t test were used to determine if catches on each design were higher or lower than average on thewhole-trap counts. Whiteflies tended to be more uniformly distributed on the surface than the thrips,which showed some grouping, especially on blue traps. Counting the insects on two 2 cm wide horizontalstrips on the top and bottom edges gave counts not signifícantly different (based on surface area) fromwhole-trap figures, for both whiteflies and thrips. This technique would reduce counting time by 70%compared with whole-trap counts, because only 30% of the trap area is counted.