Abstract
Bemisia tabaci is serious insect and constantly destabilizing the cotton production. The research was conducted to evaluate
cotton cultivars (transgenic and non transgenic) for resistance against whitefly and further correlated with weather factors
such as temperature, relative humidity and rainfall, during the cropping seasons 2010 and 2011. However, peak population
(6.36 per leaf) was recorded from FH-113 followed FH-167 and FH-114, whereas minimum population was recorded from
FH-4243 in transgenic group whereas peak population (5.24 per leaf) was recorded from FH-941 followed by FH-100 and
FH-901 while minimum population was recorded from FH-207, in non transgenic group of cultivars in the year 2010. The
incidence and abundance was much high and reaching towards two folds in the year 2011 but the trend of whitefly varied
with peak population (11.03 per leaf) recoded from FH-167 followed by FH-4243 and FH113 (from transgenic group of
cultivars) whereas a peak of 10.77 per leaf population of whitefly, recorded followed by FH-901 and FH-941 (from non
transgenic group of cultivars). FH-207 found more resistant from all ten cultivars studied in 2011. Correlation among weather
factors and whitefly population showed that rainfall was negatively correlated while temperature and relative humidity were
positively correlated with whitefly population. In addition to that situation is becoming worse because of shifting from
conventional to more advanced transgenic cultivars that are susceptible and serve as host. Moreover, climatic conditions
provide addition favor and helps in population buildup, abundance and incidence.