Larval survival after 3 d Pupation 1- Develop a rapid sampling plan for estimating chilli thrips population on roses, 2- Evaluates the efficacy of bio-rational insecticides against chilli thrips on roses under field conditions, and 3- Evaluates the effect of pruning as cultural control practice. The chilli thrips Scirtothrips dorsalis (Thysanoptera: Thripidae) is an economically important insect pest throughout tropical and subtropical regions. It has been reported affecting over 150 plant species from more than 40 different families, including fruits, vegetables, and ornamental plants. Ornamental such as begonia, coleus, coreopsis, crape myrtle, viburnum, Indian hawthorn, and roses have been reported with chilli thrips damage. It was detected in 2005 in Florida and was rapidly spread to Texas, Louisiana, Georgia, and Alabama. This insect pest produces direct and indirectly damages to host plants. Both adults and larvae preferentially attack young leaves, buds, and flowers, and fruits, causing distortion, discoloration, defoliation and stunted growing. In addition, this pest has been reported as a vector of several plant diseases such as tomato spotted wilt virus, tobacco streak virus, and peanut chlorotic fan virus. In both Florida and Louisiana, chilli thrips is now common on roses and other ornamental plants grown in the nursery industry and in established landscape. For example, KnockOut® is the number one ornamental plant sold in the USA and chilli thrips are affecting this economical industry. Due to the high cost, risks for insecticide pesticide resistance, negative impact on beneficial, and environmental, the use of insecticides as the only approach is not the best solution. Therefore, establish an eco- friendly and sustainable integrated pest management is the general goal of this project. Objectives Sampling plan for monitoring chilli thrips population Three different initial populations densities of chilli thrips were established (low, moderate, and high with 3, 9, and 27 adults /plant respectively). The chilli thrips population and damage symptom caused by the insect pest were evaluated during several generation (8 weeks). Visual sampling of fresh damage symptom was assessed in 5 terminals per plant according with following score classification: 0 = no damage; 1 = slight damage (one typical tiny eruption or scarring in the leaf); 2= moderate damage (two or three scarring in the leaf and curling is starting in the leaf; 3= sever damage (more than three scarring and complete deformation of the leaf), (Figure 1). A destructive sampling of 5 terminal per plant was conducted in order to determine the total number of chilli thrips (adults and immature stages) per terminal. In additions, 3 buds and 3 open flowers per plant were collected for counting chilli thrips. Six repetition per population density was conducted. Correlation between visual damage (severity index) and chilli thrips population per plant were conducted. Material & Methodology Efficacy of bio-rational insecticides Ornamental rose, (Rose sp Red Double Knock Out) were using under field conditions. Plants were infested with 40 adults thrips. The following bio- rational insecticides were applied four times for control chilli thrips: Beauveria bassiana Vuilleming strain GHA (BotaniGard® 22 ES) 2.5 mL/L; Metarhizium brunneum Petch stain F52 (Met-52 EC) 2.5 mL/L; Azadirachtin (Neem-X 4.5) 0.60 mL/L; SuffOil-X 10 mL/L; and Spinosad (Conserve) 0.63 mL/L. Untreated and water with Capsil (surfactant) 1 ml/L were conducted as controls. Evaluations about populations of chilli thrips and symptom damage were conducted weekly. Six repetitions per treatment were assessed. The chilli thrips population was 5.7 ± 1.3 individual / leaf before pruning and it decreased to cero at the moment of pruning. However, because the immature stage pupae can be in the ground around the plant, new adults can emerge and establish a population in the new growing tissues of the plant one and two weeks after pruning (Figure 4). Combination of pruning and application of insecticides such as Spinosad and M. brunneum can regulate the chilli thrips population on 99% and 48% respectively in comparison to the control (pruning alone). Due to the availability of new terminals, the chilli thrips population increased quickly from 0 to > 3 individuals per leaf 4 weeks after pruning. The pruning alone as cultural control practice cannot control the pest. However, in combination with insecticides the efficacy of this cultural practice can be increased. Pruning as cultural control practice Figure 4. Effect of pruning alone and in combination with bio–rational insecticides as cultural control practice to regulate chilli thrips on rose plants under field condition. Narrows represent the week when products were applied. (A) before pruning, (B, C, and D) at 0, 1 and 2 weeks after pruning respectively. Figure 1.. Fresh damage symptom caused by chilli thrips in rose plants. Severity index: (A) 0= no damage;(B) 1= slight damage; (C) 2= moderate damage; and (D) 3= severe damage. An Approach for monitoring and management of chilli thrips (Scirtothrips dorsalis Hood on KnockOut® rose under nursery Luis F. Aristizábal 1, Yan Chen 2, Ronald H. Cherry 3, Ronald D. Cave 4, and Steven P. Arthurs 1 1 University of Florida, IFAS, Mid-Florida Research and Education Center, Apopka, FL, 2 Louisiana State University Ag Center, Hammond Research Station, Hammond, LA, 3 University of Florida, IFAS, Everglades Research and Education Center, Belle Glade, FL, 4 University of Florida, IFAS, Indian River Research & Education Center, Fort Pierce, Efficacy of Bio-rational insecticides Figure 2. (G) Correlation between severity (index) and estimated chilli thrips population on rose plants at different densities. Correlation Coefficients (r 2 ) for low (0.87), moderate (0.87) and high density (0.88) respectively, according with the Exponential equation. (H) Number of chilli thrips on terminals (new leaves), buds, flowers, and severity (index) for moderate density population. New leaves without damage (A, B, and C), and with symptom damage (D, E, and F) respectively. Figure 4. Efficacy of the bio –rational product against chilli thrips population on rose plants under field conditions. Number of chilli thrips per leaf during 7 weeks. Narrow show the week when products were applied. A B B. bassiana S Results Sampling plan Pruning as cultural control practice Rose plants with high population of chilli thrips were pruning (removing all damage part of the plant and all new growing) in order to evaluate the effect of pruning alone as cultural control practice on chilli thrips population. In addition, Met -52 EC (2.5 ml/L) and Spinosad (Conserve) 0.63 mL/L) were apply at the moment of pruning, one, and two weeks later). The chilli thrips population (adults and larvae) were affected by all bio- rational insecticides in contrast with both (untreated and water). Spinosad was the insecticide with more efficacy follow by M. brunneum and Neem. Also, B. bassiana and SuffOil-X presented less chilli thrips population that the controls but high that the other products. The reduction of chilli thrips population compared with controls, as following: Spinosad (97%) M. brunneum (71%), Neem (67 %), B. bassiana (51%), SuffOil-X (48%) respectively. The figure 4 shows the chilli thrips population observed in all treatments during 7 consecutives weeks. D A B C D The chilli thrips developed through three generations during 8 weeks. In all densities, the population was increasing at the time (weeks) increased as well. Correlation between severity (index) and population of chilli thrips was observed for all densities. For total number of chilli thrips found on terminals and severity the exponential equation showed the higher correlation with r 2 of 0.89, 0.78, and 0.84 at low, moderate and high density population respectively. The number of chilli thrips (adults and immature) found on terminals, buds and flowers were, used for estimating the total number of chilli thrips per plant (Fig 2). Higher number of chilli thrips was found on terminals in contras with flowers and buds respectively. The results suggest that visual damage may be use as predictor of population of chilli thrips. Therefore, a sampling plan can be develop by establishing a severity damage threshold for chilli thrips on roses. In the future the minimal number of plants and terminals to be sampling have to be addressed C B F E D C B A G H