Comparative Effects of Chili Thrips on Eleven Pepper Varieties on Field and Greenhouse Environments in South Florida

Effects of chili thrips, Scirtothrips dorsalis Hood (Thysanoptera: Thripidae) on pepper, Capsicum spp. ‘Agriset 4108’, ‘Fresno 6022’, ‘Hot Tormenta’, ‘Hot San Ardo’, ‘Cheyenne’, ‘Hot Habanero Orange’, ‘Red Devil Cayenne’, ‘Numex Big Jim’, ‘Astry’, ‘Hot Fatalli’, and ‘Jamaican Yellow’, were tested at the Tropical Research and Educational Center, Homestead, FL, in 2011 and 2012 in greenhouse and laboratory environments.  When plants were treated with Spinetoram or untreated in a greenhouse, flower buds, cut pedicels, and total of pedicels, flowers, and fruits per plant each had no interactions between variety and treatment, while numbers of fruit and canopy volume had interactions.  Flower buds, pedicels, and total differed between varieties with ‘Astry’ and ‘Agriset 4108’ having the highest and ‘Hot Habanero Orange’ and ‘Hot Fatalli’ the lowest; Spinetoram increased numbers of pedicels and total when varieties were pooled.  ‘Hot San Ardo’ was highest and ‘Hot Fatalli’ lowest for treated canopy volume, and ‘Fresno 6022’ was highest and ‘Hot Fatalli’ lowest for treated fruit.  ‘Numex Big Jim’ was least helped and ‘Fresno 6022’, ‘Hot Tormenta’, ‘Cheyenne’, ‘Astry’, and ‘Jamaican Yellow’ most helped by Spinetoram application.  A greenhouse choice test indicated ‘Hot Tormenta’, ‘Hot Fatalli’, ‘Numex Big Jim’, and ‘Jamaican Yellow’ had the fewest thrips per plant, and ‘Astry’ and ‘Red Devil Cayenne’ had the most.  In a choice of varieties in Petri dishes in laboratory growth chambers, ‘Hot Fatalli’, had the fewest nymphs per leaf disk and ‘Agriset 4108’ had the most.  ‘Hot Fatalli’ attracted the fewest thrips, hence was the most resistant variety across three experiments, though it had the smallest plant size and lowest yields; Spinetoram improved yields of productive varieties like ‘Fresno 6022’, which may be more feasible to grow than ‘Hot Fatalli’.