Short communication. Deterioration of cotton fibre characteristics caused by cotton leaf curl disease

The effect of cotton leaf curl disease found at Burewala (Pakistan) on the ginning out turn (GOT) and the physical and chemical characteristics of cotton fibre was evaluated by comparing healthy and cotton leaf curl disease (CLCuD)-infected plants of four cotton varieties. A highly susceptible response to CLCuD was found in all varieties tested. The disease incidence ranged from 42.6 to 81.4%. Significant differences were observed between the fibre of healthy and diseased cotton plants, of all varieties, for GOT, fibre length, fibre uniformity index, short fibre index, fibre fineness, fibre bundle strength, reflectance degree (Rd-value), yellowness (+b value) and maturity ratio. The cv. CIM-473 exhibited the highest reduction in all the quality parameters studied with the exception of Rd-value which was the lowest in cv. NIAB-999. The disease also significantly affected cellulose, protein, wax and pectin content. CLCuD adversely deteriorated the cotton fibre characteristics, however the varietal difference exists. The varieties with less deteriorated fibre by CLCuD should be an essential criterion for the selection of resistant germplasm against CLCuD.