IMPACT OF SOME ORGANIC AND BIOFERTILIZERS SOIL AMENDMENTS ON THE FERTILITY STATUS, SOME SOIL PROPERTIES, AND PRODUCTIVITY OF SANDY SOILS

Abstract

A field experiment was conducted on sandy textured soil under sprinkler irrigation system during the two successive agricultural growing seasons of (2009/2010) and (2010) at Ismailia Agricultural Research Station, AgriculturalResearchCenter. Ismailia governorate, Egypt, to evaluate the effect of applying some organic soil amendments i.e.,compost at rates of (2.5, 5, and 7.5 tonfed-1), humic acid rate of (5l fed-1) and biofertilizer (Bacillus Polymxa) individually or incorporated with biofertilizer on the fertility status, some soil physico -chemical properties, and productivity of wheat plants (Triticumvulgare) C.V. Giza 168 and peanut plants (Arachishypogaeal.) C.V. Giza 4. The experiment was designed statistically as a split plots with three replicates. The main plots were located for the biofetilization and the sub plots were devoted for the organic amendments types. At the end of the growing seasons (i.e. after 6 and 4 months from plantation of wheat and peanut respectively) some hydro physical and chemical properties of the soil were determined The obtained results revealed that application of either organic amendments or bio fertilizer as individual or in combination improved fertility status of the soil as well as, the seed yields of wheat and peanut. These include, (a) Increasing available N, P, and K of the treated soil. (b) Increasing OM content in treated soil. Mixing soil conditioners together i.e. organic amendments and biofertilizer was more efficient in improving chemical properties of the soil than applying each of them alone. In this context, the maximum content of available NPK were (22.64, 13.23 and 68.41 mg kg-1 soil) and (24.14, 13.71 and 70.46 mg kg-1 soil) for N, P and K in the soil after wheat and peanut harvesting, respectively, resulted from the high rate of compost (7.5 ton fed-1) combined with biofertilizers. (c) Increases in the concentration of (N, P, and K) in the seeds as well as yields of seed. It's also noticed that yields significantly increased by increasing rate of organic fertilizer, which amounted to 1.50 times for wheat seed vs 1.95 times for peanut seed over control treatment by treating the soil with compost at rate of ( 7.5 tonfed-1), in sequence. Applied conditioners significantly improved the hydro physical properties of the soil. These include, (a) decreasing soil bulk density as well as macro porosity (drainage pores) on the expense of micro ones. Therefore, water holding pores were increased, (b) increasing retained moisture in the soil at field capacity, wilting point and available water because the increase in water retained in the soil at field capacity is far beyond that at wilting percentage, available water was highly increased. (c) Decreasing soil hydraulic conductivity. Generally, mixing both types of soil conditioners together i.e. organic amendments and biofertilizer was more efficient in improving physico- chemical properties of the soil than applying each of them alone.