COMPARATIVE PERFORMANCE OF UPLAND AND DESI COTTON CULTIVARS AT GERMINATION STAGE OF GROWTH UNDER DIFFERENT SALINITY LEVELS
Ali Zafar Jafri1 and Rafiq Ahmad2
1Government College of Science, Multan, Pakistan.
2Botany Department, Karachi University, Karachi, Pakistan.
Abstract: Sixteen commonly grown cultivars in Pakistan belonging to upland (G. hirsutum L.) and desi (G. arboreum L.) cotton were studied to work out comparative salt tolerance at germination stage. Four different salinity levels viz. 0.25%, 0.5%, 0.75% and 1.0% were raised by mixing NaCl, MgSO4 7H2O CaCl2 2H2O : NaHCO3 (9:8:2:1). Delinted cottonseeds were incubated at 30oC+2oC and germination was recorded upto 96 hours of incubation in darkness. Increasing salinity levels delayed seed germination rather to inhibit this biological process. This delay was significant upto 48 hours. However, onward delay was insignificant in most of the cotton cultivars. Sixty precent or more germination in 1% salinity level after 48 hours of incubation period was selected as the criteria to compare the salt tolerance at germination. Upland cotton cultivars B557, Rehmani, K68, Niab 78, Sarmast, Qalandari and desi cotton cultivar Rohi, Ravi and SK 10/19 appeared as most salt tolerant under 1% salinity level at germination.
Keywords: Cotton cultivars, delinted cottonseed, germination stage, growth, salinity level, salt tolerance.