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Not AvailableAnalyses of the scenario of cotton sap feeders [leaf hoppers, Amrasca biguttula biguttula (Ishida), thrips, Thrips tabaci Lindeman and whiteflies, Bemisia tabaci Gennadius] based on their population dynamics (numbers/three leaves/plant) for north zone cotton growing locations viz., Faridkot (30.40°N, 74.45°E), and Ludhiana (30.91°N, 75.85°E) of Punjab, Hisar (29.15°N, 75.70°E) of Haryana and Sriganganagar (29.92°N, 73.88°E) of Rajasthan indicated significantly higher A. biguttula biguttula infestation during 2013 (7.0) and 2014 (14.0) over previous eight seasons, increasing whitefly incidence after every two years, and declining T. tabaci infestation at Faridkot (Punjab). Bemisia tabaci incidence was highest during 2013 (26.4) and 2014 (26.9) at Hisar. Peak population and period of sap feeders varied across locations and population between seasons of the same location differed during early and late crop growth stages. The importance of sap feeders was of the order: A. biguttula biguttula > B. tabaci > T. tabaci at Ludhiana (Punjab). Thrips tabaci and B. tabaci were dominant at Sriganganagar (Rajasthan). Increasing trend of A. biguttula biguttula, T. tabaci and B. tabaci were observed over years at all locations but for declining population levels of T. tabaci at Ludhiana (Punjab) and Sriganganagar (Rajasthan). Multiple linear regression forecast models in respect of sap feeders for the four locations were developed using SAS 9.3. Minimum and maximum temperatures besides rainfall significantly predicted the population of each sap feeder for the current, 1 and 2 weeks after.Not Availabl