EFFECT OF TOPPING PROCESS FOR MAIN STEM IN QUALITATIVE CHARACTERS OF SOME GENOTYPES OF UPLAND COTTON (Gossypium hirsutum L .).

Abstract

A field experiment was carried out in fields of College of Agriculture-University of Tikrit during Summer season 2013, The experiment was included two factors, first :six genotypes ( Coker 310,Lachata , Dunn-1047 , Montana , Dise and W888 ) while second factor was: three treatments of topping (without topping , topping after 40 days from planting and topping after 60 days from planting ) aimed to study topping process for six genotypes of upland cotton and it is effect on the qualitative characters of genotypes . using R. C. B. D. design as a split plot arrangement with three replicates ,the genotypes were as a main plot and treatments of topping were as a sub plot. The results showed: The genotypes were significantly differed in most characters except : elongation , uniformity ratio ,and good cotton percentage, While effect of topping process was significant just in finness and maturity percentage characters . The interaction between genotypes and treatments of topping was significant for all characters except: elongation and good cotton percentage.