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Article HistoryThe field study was conducted on at the experimental field of SALU -Khairpur during, 2016. Two hundred eggs were kept for each replication on cotton plants grown in large pots. When eggs hatched, the life table parameters such as; apparent mortality, survival fraction, mortality survivor ratio, indispensable mortality and k-value were studied. Natural enemies such as; Chrysoperla carneae, lady bird beetles, Spiders and Anasius bambawallae were found active on the potted and surrounding cotton plants in the field conditions. The total mortality in egg stage went to 19.00%. The mortality percentages of 1 st instars due to natural enemies recorded was (18.73%) while, in 2 nd instars (13.13%) mortality was recorded. The total combined mortality in 1 st and 2 nd instars was recorded (26.34%) and (15.64%), respectively. However, the mortality of 3 rd instars and pupae due to parasitoids were recorded (7.28%) with the total mortality (10.26%) and the total mortality (54.83%) in cotton potted plants was recorded. Consequently, (45.17%) of adults survived with male and female ratio as ♂1:6.52♀, respectively. The highest apparent mortality was (26.34%), indispensable mortality (96.89) and k-value (0.13) recorded in 1 st instar. The maximum survival fraction was recorded (0.90) in third instars/pupae with the total k-value generations (0.35). The study revealed that the predators and parasitoids should be encouraged in cotton field when mealybugs appear, because predators are highly voracious feeder of 1 st and 2 nd instars whereas; the parasitoid, A. bambawallae is known as main controlling natural enemy of cotton mealybug.Contribution/ Originality: This study documents over the biological parameters of cotton mealybug to check its, egg laying, mortality, survivor ratio, total life span, fecundity, fertility, different life stages, predators activity and aboitic factors with the different equations about this vigorous pest under cotton field conditions.

The research work was carried out during Kharif season, 2018 to investigate the varietal resistance of six Bt cotton varieties i.e., FH-Lalazar, SS-32, Bt-CRIS-508, CRIS-510, FH-142 and CRIS-533 against sucking pests, jassid, whitefly, thrips and mealybug under field conditions. The maximum resistivity against jassids was observed in SS-32 (1.98) per leaf followed by Bt-CRIS-508 (2.01), CRIS-533 (2.10), CRIS-510 (2.11), FH-142 (4.02) and FH-Lalazar (4.06).Against whitefly SS-32 gave maximum resistance (5.99) per leaf followed by CRIS-533 (6.00), CRIS-510 (8.55), Bt-CRIS-508 (8.93), FH-142 (9.12) and FH-Lalazar (11.04). Against thripsSS-32 variety showed maximum resistance (8.57) per leaf followed by CRIS-510 (8.81), CRIS-533 (8.87), Bt-CRIS-508 (9.50), FH-142 (10.27) and FH-Lalazar (15.31), while against mealybug Bt-CRIS-508 found resistive (0.42) followed byCRIS-510 (0.43), FH-142 (1.49), SS-32 (1.88), CRIS-533 (1.98) and FH-Lalazar (2.02).The overall results showed that cotton variety SS-32 gave better resistance against overall sucking pests (4.60) per leaf followed by CRIS-533 (4.74), and CRIS-510 (4.97), while varieties Bt-CRIS-508 and FH-142 showed moderate resistance against sucking pests (5.21) and (6.23), respectively however; variety FH-Lalazar had not shown enough resistance (8.11) against all the four mentioned sucking pests, so cotton variety FH-Lalazar was considered as most susceptible Bt variety and SS-32 variety was found to be most resistive variety against all the four sucking pests except mealybug. So it is suggested that the variety SS-32 should be cultivated as it is less attacked by sucking pests.