Study and assessment of compost of different organic mixtures and effect of organic compost tea on plant diseases

摘要

Four compost treatments representing different organic mixtures were studied: ud- Treatment T1: 100% cattle manure ud- Treatment T2: 80% cattle manure and 20% sheep manure ud- Treatment T3: 70% cattle manure, 20% sheep manure and 10% poultry udmanure. ud- Treatment T4: 50% cattle manure, 20% sheep manure, 20% poultry manure udand 10% crushed wheat straw. udThe results showed that the temperature was higher for the 4th treatment which udwas richer in carbon than the other treatments. udThe initial alkaline pH decreases for all treatments and approaches neutrality udat the end of composting process, essentially for the first treatment. There is also a uddecrease in the carbon / nitrogen ratio. udAt the maturity stage, a compost tea was prepared from different composts udafter five days extraction period. The four compost teas were tested on different plant udpathogens: Fusarium roseum var sambucinum, Fusarium oxysporum, Fusarium udoxysporum, Fusarium solani var coeruleum, Phytophtora erythroseptica and udRhizoctonia solani. All the treatments were efficient against these pathogens and udespecially the 4th treatment which considerably reduces also the dry rot of Fusarium udsolani in potato tubers during storage. This is considered an important result since udFusarium solani seems to be the most important pathogen in Tunisian soils. udOur studies should be carried out in order to determine the better combination udof organic mixtures, the better method of compost tea extraction (aerobic or udanaerobic), the optimal period of extraction and doses to be used.ud