Evaluation of three cultivation practices for early cotton establishment and improving crop profitability

Cultivation practices permitting earlier sowing of cotton (Gossypium hirsutum L.) in Greece are required to maximize yields and facilitate harvesting. An experiment was conducted for 2 years in Central Greece to evaluate two alternative systems. The experiment was carried out in a Vertic Cambisol and a Typic Regosol field. Cultivation practices tested were: (1) conventional tillage (CT) and sowing in a flat field, (2) ridge tillage (RT), using autumn ridging and (3) sowing in a flat field under clear plastic film (PF). Early and normal sowings were compared. The effects of the treatment on the crop establishment, growth and yield, as well as on the soil physical properties, were studied. Performance evaluation of the machinery was carried out. The cost of cultivation practices was estimated. Results of soil physical properties were similar for both years. Soil water contents from sowing to plastic removal in 2000 were 14.2, 13.5 and 18.0 g/100 g and temperatures for the same period at 0.04 m depth were 17.7, 18.1 and 19.8 °C for CT, RT and PF, respectively. PF resulted in higher emergence and higher plants with smaller roots. Average yields of seed-cotton in early sowing were 4936, 4591 and 4033 kg/ha for PF, RT and CT, respectively. In late sowing, yields in RT and in CT did not differ significantly. Ridge tillage machinery saved 13.6 kWh/ha (20.9%) compared to conventional tillage machinery. The higher yields under plastic film compensated for the higher cost of the practice at the present prices of seed-cotton.