EVALUATING BORON-USE-EFFICIENCY OF TWENTY COTTON GENOTYPES OF PAKISTAN

Abstract

Boron (B) deficiency has been identified as a major yield limiting factor for sustainable cotton production around the globe, including Pakistan. Identification and adoption of B-use-efficient cotton genotypes is therefore crucial for low-B-input sustainable cotton production. A pot experiment was conducted in a completely randomized design with four repeats to categorize 20 selected cotton genotypes of Pakistan for their B-use-efficiency involving deficient (0 kgha-1) and adequate (2 kgha-1) levels of B. The cotton genotypes were ranked following two different methods to ensure ranking validity. Boron deficiency generally reduced biomass production and B uptake of all cotton genotypes. However, B-use-efficient cotton genotypes accumulated more B and produced more biomass under B-deficiency stress. Boron deficiency reduced plant height, number of leaves per plant, leaf area, shoot dry weight, shoot B accumulation and shoot B uptake of all genotypes (by 6, 14, 15, 8, 26 and 31%, respectively). Genotype CRIS-342 was ranked as ‘non-efficient’ due to its low biomass production under B-deficiency stress. Interestingly, cotton genotype IR-NIBGE-1524 exhibited wide adaptation at both the levels of B and hence ranked ‘efficient-responsive ’cotton genotype. The study concluded that the IR-NIBGE-1524 could be the most potential candidate for both the low- and high-B-input sustainable agriculture.

Keywords

• B uptake
• B-use-efficiency
• cotton genotypes ranking
• genotypic variation