FIELD APPLICATION IN MAIZE CULTIVATION OF COMPOST AND COMPOST SOURCED SOLUBLE AND INSOLUBLE ALKALINE HYDROLYZATES

摘要

Utilization of compost as substitutes of mineral fertilizers is a current agricultural practice which environmental vantages have been largely demonstrated. In previous studies it was demonstrated that upgraded substances could be obtained by alkaline hydrolysis of composts. These substances consisting in a soluble and an insoluble fraction exhibited good performance as organic fertilizers. The fertilizing effect of these substances has been assessed on horticultural species, grown in pot and greenhouse cultivations. This study reports the application of two composts (a green compost and a mixed compost) and their soluble and insoluble hydrolyzates in a field cultivation of maize. Each material was applied on three random plots and the results, expressed as soil properties, height and weights of the plants and weight of the ears and kernels, were compared with those obtained on non amended plots and mineral fertilized plots. The best results were obtained in the plots fertilized with the mineral fertilizer, the mixed compost and the soluble hydrolyzates of the composts. The minor performance of the green compost was likely due to its relatively low nitrogen content. The insoluble hydrolyzates, although allowing a significantly minor plant growth, gave the same results in term of dry weight of kernel per plant than the mineral fertilized control. Therefore, their application in maize cultivation can be recommended with an economical vantage since they are by-products of the preparation of the soluble fractions which can find alternative industrial applications such as biosurfactants.