ENVIRONMENTAL IMPACT OF USING AQUEOUS EXTRACTS OF SOME AGRICULTURE RESIDUES AND THEIR EFFECTS ON GROWTH, YIELD AND SOME YIELD COMPONENTS OF SOME PLANTS

There is a great need for intensifying agricultural production in Egypt. In this respect, an attempt was done to determine the effects of plant extracts from some agricultural residues such as rice straw, Bagasse, and soybean meal when applied with or without nitrogen mineral fertilizers on growth parameters, chemical components and yield of wheat and barley plants. Two experiments (pot and field) were carried out at Giza, Agricultural Research Station, during winter season of 2010/2011. Results of pot experiment confirmed that the growth parameters of wheat plants affected by applied of aqueous agricultural residues extracts such as shoot length and dry weight compared to control treatment (treated with recommended dose of mineral fertilizer only). The field experiment demonstrated that among the extracts tested, 100% rice straw extract follows by 50% bagasse with 50% nitrogen mineral fertilizer were highly effective on yield relative to mineral fertilizer only as a control. Regarding to the chemical and biochemical parameters, the highest values of nitrogen and potassium% were recorded in treatment of 25% soyabean meal extract with 75% nitrogen compared to control. Phosphorus content showed increasing at 25% mixture of different extract with 75% nitrogen mineral fertilizer treatment. The highest value of crude protein was observed at treatment of 25% soyabean meal extract with 75% nitrogen mineral fertilizer followed by 25% rice straw extract with 75% nitrogen mineral fertilizer compared to control. The highest value of total carbohydrate was observed in treatment of 100% bagasse extract, followed by 100% mixture of different extract treatment then 50% rice straw extract with 50% nitrogen mineral fertilizer compared to control, respectively. The highest value of Indole acetic acid (IAA) was recorded in treatment of 100% rice straw extract. For gibberellic acid, the highest value was recorded in treatment of 100% soybean. From the results obtained, it could be concluded that, some extracts can be used for reducing the dose of nitrogen fertilizer, reduce the high cost of buying inorganic fertilizers, and thus reduce pollution resulting from the extra-use of these fertilizers and also reduce the cost of agricultural production. However, more studies are needed to determine the exact mechanism(s) that lead to realize improvements.