The effects of nitrogen level and plant density on important agronomic and fiber quality properties in cotton (Gossypium hirsutuml.)

This study is executed in Söke/Aydın Güllübahçe neighborhood in order to determine if plant's nitrogen need increases based on plant density and to determine the most suitable nitrogen doses for quality and yield. In this study Claudia cotton species is used as material. Experiment executed based on split parcels experiment pattern with three replications. In main parcels plant density, in sub parcels nitrogen doses are studied. Two plant density level as sparse (over 15 cm distance) and non- sparse; four nitrogen levels as 12, 18, 24 and 30 kg N per decares is applied. In experiment seed cotton yield, number of days till first boll opening, number of monopodial branches, number of sympodial branches, plant height, number of bolls, seed cotton per boll, ginning percentage, 100 seed weight, fiber length, fiber maturity, fiber strength, fiber fineness properties are observed. In experiment based on application methods it's determined that plant density is statistically not significant for seed cotton yield, number of days till first boll opening, number of monopodial branches, number of sympodial branches, plant height, number of sympodial, ball weight per ball, ginning percentage, 100 seed weight, fiber length, fiber maturidy, fiber strength, fiber fineness. It's determined that decreasing plant density increased the cotton yield, the highets yield is observed on sparse plant density. In experiment, effect of nitrogen dose on plant density statistically significant for ginning percentage, not significant for seed cotton yield, number of days till first boll opening, number of monopodial branches, number of sympodial branches, plant height, number of bolls, seed cotton per boll, 100 seed weight, fiber length, fiber maturity, fiber strength, fiber fineness. In this study its concluded that there's no need for thinning for aftercrop cotton, optimal nitrogen level is 12 kg/da. Keywords: Cotton, Plant Density, Nitrogen, Yield, Fiber Properties