IMPROVING YIELD AND FIBRE QUALITY OF NEW COTTON VARIETIES THROUGH FERTILIZER MANAGEMENT AND SPACING

Abstract

The research study comprising five experiments were carried out at Cotton Research, Training and Seed Multiplication Farm, Sreepur, Gazipur during the cotton growing season (July – February) of 2015 - 2016, 2016 - 2017 and 2017 – 2018 with a view to investigate the yield and fiber quality improvement of newly released three inbred cotton varieties (CB-13, CB14,and CB-12}

by using different levels of fertilizer and plant spacing. The results revealed that, the variety CB-14 was found superior among the tested three varieties in respect of producing maximum bolls plant -1 , single boll weight, seed cotton yield, staple length and staple strength, and lowest micronaire value in all the years. Improving cotton yield and fibre quality through fertilizer management, was observed that yield and fibre quality decreased under excessive higher fertilizer doses in experiment 3. Maximum number of bolls plant (22.99), single boll weight (5.45 g), seed cotton yield (2891 kg ha -1 ) and minimum micronaire value (4.21 µg/inch) were recorded when the crops were grown using 75% higher dose of fertilizer than recommendated dose of fertilizer (RDF) in experiment 5 but in the case of fibre quality, 50 % higher dose than RDF produced maximum staple length (30.98 mm) and uniformity ratio (84.72 %) were recorded in experiment 5. It was also observed that yield contributing characters and fibre quality attributes increased with the wider spacing except the seed cotton yield, where higher seed cotton yield 3414 and 3325 kg ha -1 , respectively were observed with intermediate spacings of 60 × 30 cm and 75 × 30 cm found in experiment 4. Higher doses of fertilizer with closer spacing 45 × 30 cm preformed the highest seed cotton yield (3099 kg ha -1 ) observed in experiment 5. Maximum seed cotton yield, gross margin and benefit cost ratio were recorded with 75% higher than RDF × (45× 30 cm) spacing in all the tested varieties. For economic point of view, it can be concluded that 75% higher dose than RDF and the 45 × 30 cm spacing was found more profitable for all the cotton varieties under study..