TESTING THE PERFORMANCE OF COTTON-WHEAT/ MAIZE RELAY-YARD LONG BEAN CROPPING PATTERN TO ESTABLISH A RATIONALE FOR PROFITABLE COTTON CULTIVATION

Abstract

An experiment was carried out in the field of Cotton Research, Training & Seed Multiplication Farm, Cotton Development Board, Sadarpur, Dinajpur during August 2005 to July 2006 to find out whether wheat or maize as the relay crop with cotton and yard long bean as the third crop, can be included to develop. a cottonwheat/maize relay-yard long bean cropping pattern for maximizing land use and increasing total production in order to establish a sustainable cotton production system. The experiment was set up in split-plot design with four replications. The treatments were: (A) in main plots- (1) plain land and (2) raised bed; and (B) in subplots- (i) sole cotton, (ii) cotton-maize (as relay)-yard long bean and (iii) cottonwheat (as relay)-yard long bean. Every crop received respective recommended doses of fertilizers. The initial and post harvest soils were analyzed for pH, organic matter, available N, P, K, S, B and Zn. Seed cotton yields and yield contributing characters recorded for all the treatments of main plots and sub-plots and their interactions did not differ significantly indicating that relaying maize or wheat in raised bed or plain land, in the first picking stage of cotton growth in the cotton based cropping patterns, did not affect seed cotton yield. Wheat grain yields were higher in raised bed (2.03 t ha’') than in plain land (1.37 t ha’'). Number of spikes per square meter and harvest index percentage were higher in raised beds (281 m” and 34.01 %) than in plain lands (240 m7 and 25.48%). Maize grain yields in raised bed (7.44 t ha’) and in plain land (7.16 t ha’') were statistically similar. Yard long bean produced green vegetables (2.36-2.66 t ha’ pods) in addition to adding some amount of biomass into the soil through leaf shadding and plant residues. Extra output can be harvested from second crop i.e. maize or wheat relay and yard long bean as the third crop in such triple cropping system. Total production was always higher for the double (cotton-wheat or maize) or triple cropping systems (cotton-wheat or maizeyard long bean) registering more profit over sole cotton in case of both plain land and raised bed conditions. Gross return (Tk. 232080 ha™') and benefit cost ratio (1.67) were higher in cotton-maize-yard long bean system followed by cottonwheat-yard long bean; and it was the lowest in sole cotton cultivation both in plain land (Tk. 86120 ha’! and 1.44) and raised bed (Tk. 88500 ha! and 1.28) conditions. This cropping pattern can be practiced in Bangladesh for profitable and sustainable cotton production.