Comparison of Cotton Growing in Flat Field in Ridges and Under Plastic Cover

Abstract

Methods permitting earlier sowing of cotton (Gossypium hirsutum L.) in Greece are required to maximize yields. An experiment was conducted for two years in Central Greece to study the effects of practices permitting earlier sowing. The experiment was carried out in two different fields, a C and a lime CL white colored field. Early and normal sowing were compared. Cultivating practices were: 1) Conventional tillage and sowing in flat field (CT), using fall plowing, 2) Ridge tillage (RT), using fall ridging with subsoiling, and 3) Sowing in flat field under clear plastic film (PF), using fall plowing. Energy requirements of all implements, soil temperature, moisture and cone index, plant emergence, vegetative characteristics and yield were measured. Ridge tillage machinery saved 13.6 kWh per ha, 21,5% less than conventional tillage. Raised soil and air temperature under plastic film was the main factor, which permitted the application of the desirable early planting without the risk of unfavorable weather conditions. Sowing under plastic film, for both fields and years, resulted in faster and higher emergence percentage, earlier maturing and higher yield in superiority. In 2001 yield of seed cotton at C field was 485, 414.7 and 408.3 g/m2 for PF, RT and CT respectively. The highest level of soil moisture was under PF and the lower at the peak of the ridge. Plants in ridges had larger root system and plants in PF had the smallest root system.