Agronomic use of biotechnologically processed grape wastes

Grape waste was composted by biodegradation and subsequently used as an org anic fertilizer for 20 day-corn. Combinations of recently compressed grape waste and hen droppings (10% w/w) were prepared to study the activating eff ect of hen droppings and the effect of aeration on the composting process. The final hydrogen potential (pH), %C, %N and CM ratio, indicated an adequa te development of the bioprocess. Satisfactory results were observed when t he products were applied at several doses (1000-4000 kg/ha) as a soil condi tioner for corn seed germination in greenhouses. Only the addition of hen d roppings had a significant effect (P < 0.05) on corn dry matter (14% increa se). A dose of 3000 kg/ha was considered as optimal and was used supplement ed with triple superphosphate (TSP) in agronomic trials. All the treatments produced greater corn dry matter (P < 0.05) than the chemical industrial f ertilizer used as a control (0.52-0.71 g/pot for the organic fertilizers vs 0.45 g/pot for the control). Anaerobic conditions and hen droppings additi on significantly produced (P < 0.05) higher corn dry matter. (C) 2000 Publi shed by Elsevier Science Ltd. All rights reserved.