The effect of sulfuric acid con centration and temperature on delinting, seed germinability and vigor of Sahel and Varamin cultivars by standard germination test

Cotton (Gossipum hirsutumL.) is one of the most important agricultural and industrial crops in the world and Iran. Seed in agricultural crops including cotton, is the most important production input and cotton seed delinting is the most important processing step which is done by thermal, chemical and mechanical methods. In order to evaluation effect of three sulfuric acid concentrations including30, 40 and 50% and three temperatures of 40, 60 and 80oc,an experiment was conducted by standard germination test on seed germinability and vigor of Sahel and Varamin cultivars. Traits of investigation were included required time for delinting, seed final germination percentage, length, wet and dry weight of stem and radicle. The results was showed that using of diluted sulfuric acid by 30% concentration and temperature between 40-60 (depend on cultivar) was the optimum method for delinting, so that in Sahel and Varamin, optimum temperature was 40 and 60oc at the time of 90 and 30 minute, respectively. Also, Varamin cultivar was tolerant to high temperature in delinting than Sahel.