EFFECT OF DIFFERENT NITROGEN SOURCES AND SOIL SOLARIZATION ON GREEN ONION PRODUCTIVITY FOR EXPORTATION

Two field experiments were carried out during two successive winter seasons 2007/2008 and 2008/2009 at National Research Centre Experimental Farm, Nubaria, Behira Governorate, Egypt to study the effect of different nitrogen sources (chicken manure, cattle manure and ammonium sulfate at rate 70 kg N /fed) and soil solarization (6 weeks duration) on green onion production. The results showed that soil surface temperature was higher at solarized soil fertilized with cattle manure compared with non-solarized. Under solarization, soil temperature decreased with increasing soil depth. Soil solarization reduced the total number and fresh and dry weight of weeds significantly, while different nitrogen sources had insignificant effect. Different nitrogen fertilizers and soil solarization improved green onion plant growth characters expressed as number of plant leaves, bulb base diameter and plant fresh and dry weight significantly. Both chemical fertilizer and soil solarization increased fresh weight of plants significantly. The highest number of exportable green onion plants was obtained from chicken manure and soil solarization treatment. Protein, total free amino acids and indoles were increased significantly with chemical fertilizer. While total and soluble sugars were increased significantly with cattle manure fertilization.