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Environmental factors or parameters play a pivotal role in the cotton production. These factors also affect the life cycle, outbreaks and spread of insect pests at a great magnitude that either force them to acclimatize themselves to these varying climatic factors or escape Abstract | Cotton is considered as the back bone of Pakistan's economy. It is attacked by several sap sucking and chewing insect pests during its growth, which results in the significant reduction of the cotton yield. Among these insect pests, Amrasca biguttula biguttula 'Jassid' are the most destructive ones. Beside these insect pests, environmental factors also affect the cotton production as well as population fluctuations of insect pests. The current study was designed to measure the impact of different meteorological limitations i.e. temperature ( o C), relative humidity (RH) and rainfall (RF) on population fluctuation or dynamics of the A. biguttula biguttula. It was found that there is a direct relationship between A. biguttula biguttula population and temperature. While, no significant correlation of A. biguttula biguttula population with the RH except two years (2014 and 2016) where, it has shown positive correlation. RF mostly has significantly positive correlation with A. biguttula biguttula population. During the study duration, it has also been found that A. biguttula biguttula population was highest during the month of June and lowest during the month of April. Similarly, during 2015 A. biguttula biguttula population was highest and during 2013 and 2014 it remains the lowest. The study reveals that, these weather factors show a vital role in the population dynamics or fluctuation of Jassid and weather based predictive models are very effective to manage insect pests.

C otton contributes significantly in foreign earnings being a non-food cash crop. It accounts for 0.8 percent in Gross Domestic Product and 4.1 percent in value added in agriculture. Though, this year the cotton production was 6.9 percent less than the target. This is predominantly due to the shortage of irrigation water, un-favorable weather conditions and heavy flare up of sucking and chewing pest complexes (Anonymous, 2020).Both sucking and chewing type of insect pest are observed on cotton crop, more than 1346 mites and insect pests have been recorded throughout the world. In Pakistan, 145 insect pests were recorded (Haque, 1994). These insect pests cause significant damage during cotton production. The estimated losses fall within the range of 20-40 percent due to these pests and diseases (Ahmad, 2003).Many types of natural enemies also exist in cotton crop in addition to these insect pests. It has been ob-Abstract | Cotton crop is attacked by several sucking (whitefly, thrips and jassid) and chewing (american bollworm, spotted bollworm, pink bollworm and armyworm) insect pests, which severely affects its quality and quantity. Cotton also contains the populations of parasitoids i.e. Trichogramma spps., Braconid wasps and Encarsia spps., which act to reduce the population of these notorious insect pests. Cotton plants shows genetic resistance or tolerance against these insect pests. In the current experiment six varieties of cotton i.e. CIM-496, CIM-534, NIAB-111, MNH-786 and Bt-121 were sown in the field under sprayed and un-sprayed condition to check the genetic resistance or tolerance against these insect pests and to also check the population of the parasitoids. It was observed that MNH-786 and Bt-121 were the most resistant or tolerant varieties against the insect pests but the pesticide application would still be required to keep their population below the economic threshold level. Population of insect pests and parasitoids significantly reduced using insecticides. In Pakistan, environmental friendly insecticides need to be encouraged to avoid their deleterious effects on beneficial insects.