PERFORMANCE OF COTTON HYBRID AND INBRED VARIETIES UNDER DIFFERENT NUTRIENT LEVELS

Abstract

A field study was conducted at Cotton Research Training and Seed Multiplication Farm, Sreepur, Gazipur from July 2011 to February, 2012 to investigate the influence of different levels of fertilizer on a number of hybrid and inbred varieties of cotton in respect of growth, yield components and yield, and fibre quality attributes. The experiment comprised three cotton genotypes (i) HSC-4 (hybrid), (ii) DM-2 (hybrid) and (iii) CB-12 (inbred) variety and five levels of fertilizers (i) Control (without fertilizer), (ii) 25% less than recommended dose, (iii) Recommended dose (RDF: 120, 52, 131,27:N,P,K,S kgha -1 ), (iv) 25% higher than recommended dose and (v) 50% higher than recommended dose. The experiment was laid out in a Randomized Complete Block Design (factorial) with three replications. The results revealed that seed cotton yield, bolls plant -1 , ginning out turn differed among the varieties. The highest seed cotton yield and ginning out turn were obtained in hybrid HSC-4 and that of the lowest received from CB-12 variety. Increasing levels of fertilizer maintained higher values of all the parameters except days to first flowering, lint index and ginning out turn. The tallest plant (111cm) and maximum days to boll opening (129.3), number of no. of bolls plant

(27.08), seed cotton yield (2174 kg ha - ii - -1 ), lint yield (953kgha -1 ), seed index (9.49), staple length (1.2inch), micronaire value (4.3), fibre strength (83.70 psi), uniformity ratio (48%) were observed in the plot where 50% higher than RDF was applied. Plant height, bolls plant -1 , individual boll weight, lint yield and ginning out turn showed higher value with the interaction of HSC-4 x 50% higher than RDF. The highest seed cotton yield (2406 kg ha -1 ) Gross return (144360 tk ha -1 ) Gross margin (75358tk ha ), BCR (2.09) and seed index were obtained with the combination effect of CB-12 x 50% higher fertilizer than RDF. For economic point of view, the results indicate that CB-12 inbred variety x 50% higher fertilizer than RDF was more profitable than any of the other treatment combinations.