RESPONSE OF COTTON GENOTYPES TO BORON UNDER B-DEFICIENT AND B-ADEQUATE CONDITIONS

Abstract

Balanced boron (B) application is well-known to enhance the cotton production; however, the narrow range between Bdeficiency and toxicity levels makes it difficult to manage. Cotton genotypes extensively differ in their response to B requirements. The adequate dose of B for one genotype may be insufficient or even toxic to other genotype. The effects of boron (B) on seed cotton yield and its various yield associated traits were studied on 10 cotton genotypes of Pakistan. The pot studies were undertaken to categorize cotton genotypes using B-deficient (control) and B-adequate (2.0 kg B ha-1) levels arranged in CRD with four repeats. The results indicated that the seed cotton yield, yield attributes and B-uptake of genotypes were comparatively decreased in B-deficient stressed treatment. Genotype NIA-Ufaq exhibited wide range of adaptation and ranked as “efficient-responsive”, as it produced higher seed cotton yield under both B-regimes. SAU-2 and CIM-506 were “highly-efficient” and remaining all genotypes were “medium-efficient”. Genotype Sindh-1 produced low seed cotton yield under B deficient condition and ranked as “low-efficient”. B-efficient cotton genotypes can be grown in B deficient soils without B application.