Management of bacterial blight of cotton (Xanthomonas campestris pv. malvacearum) through plant extracts and its impact on yield components of bt cotton varieties
By: Abdul Rashid, Muhammad Ehetisham-Ul-Haq, Rehan Fakhir, Muhammad Atiq
Key Words: Cotton, Xanthomonas campestris pv. Malvacearum, Bacterial blight of cotton, Azadirachta indica, Moringa oleifera.
Int. J. Biosci. 9(1), 90-98, July 2016.
Cotton is known as the king of fibers. Bacterial blight of cotton is a devastating cotton disease of subtropical and tropical regions. Five plant extracts Azadirachta indica, Moringa oleifera, Cassia fistula, Allium cepa and Eucalyptus oblique were evaluated at 5%, 10% and 15% concentrations against colony growth of Xanthomonas campestris pv. malvacearum using inhibition zone technique. At 15% concentration, Azadirachta indica was most effect to inhibit bacterial colony with respect to others. Plants extracts having maximum inhibitory effect against the pathogen were evaluated on four different Bt-cotton varieties in field conditions against the disease and biological parameters. Comparing to the extracts applied, Azadirachta indica considerably reduced the disease incidence on all experimental varieties (Bt-866, Bt-113, Bt-92 and Bt-802). Plants of 802 variety sprayed with Neem extract were more in height (93.8 cm), number of bolls (40) and leaves (106) as compared to the other plants of different varieties where other extracts applied. The extract of Azadirachta indica at 15% concentration can be used as alternative to antibiotics to manage the bacterial blight disease of cotton.