Cotton Aphid Aphis Gossypii L. (Homoptera; Aphididae); a Challenging Pest; Biology and Control Strategies: A Review.

Cotton aphid (Aphis gossypii) is a key pest of cotton crop. The indiscriminate use of insecticides and pesticides during 1930’s and latter to control insects pests, developed resistance in cotton aphid against these chemicals resulting in outbreak of this pest. Cotton aphid has a major impact on quality and yield of cotton which emphasizes the need to manage this notorious pest. The main goal of this review is to highlight various strategies viz., biological, chemical and cultural control for cotton aphid management. The selection of suitable control strategy is made on by viewing the severity of cotton aphid outbreak. Furthermore, the role of transgenic crops in lowering cotton aphid population is also described. However, the preservation of the cotton aphid's natural enemies could be an ecologically sustainable method of maintaining the aphid population below threshold level.

Isolation and Characterization of Halophilic Bacterial Strains from Saline Waters of Khewra Salt Mines on the Basis of 16S rRNA Gene Sequence.

Halophiles are salt loving microbes optimally growing at high concentrations of salt. Khewra salt mines of Pakistan provide extreme saline conditions where enormous halophilic microbial biota thrives. The present study aimed at isolation and molecular identification of bacterial strains from saline waters of Khewra salt mines. Using halophilic media, nine halophilic bacterial strains from saline water bodies were cultured and studied under optimized growth conditions (NaCl, pH and temperature). Bacterial growth at different NaCl concentrations was measured at 600nm wavelength, showing optimal growth at 1.5M NaCl. 769bp size 16S rRNA gene was amplified for molecular identification of bacterial strains. The amplified genes of the strains FA2.2 and FA3.3 were sequenced and their homology with other bacterial strains was analyzed. The results showed FA2.2 shared maximum homology with Bacillus anthracis strain while FA3.3 showed close resemblance with Staphylococcus saprophyticus subsp. bovis. Isolated halophilic bacterial strains possess potential for various biotechnological applications. They could be manipulated for synthesizing transgenic crops tolerating high salinity boosting the agricultural yield. Moreover extremozymes of these bacteria holds great industrial importance.