THE EFFECT OF NITROGEN FERTILIZER WITH VAM MYCORRHIZAL INOCULATION ON YIELD AND NUTRIENTS UPTAKE BY TWO WHEAT (Triticum aestivum L.) VARIETIES GROWN IN CLAY SOIL

Field experiment was carried out at Kafr El-Sheikh Agriculture College Farm during 2000/2001 season, using split-split plots design with four replicates. The nitrogen fertilizer (urea 46% N), was applied at the rate of 60 kg N/fed. Urea was added in 3 different ways. One dose applied at sowing, two equal doses at sowing and tillering stages and three equal doses at sowing, tillering and booting stages. The effect of vesicular arbuscular mycorrhizal fungi (VAM) was studied, inoculation with one VAM (Glomus fasciculatum).
                The effect of doses of nitrogen fertilizer with and without (VAM) inoculation (mycorrhizal fungi), ultimately maximize the yield of two wheat varieties, Sakha 69 and Giza 155, and the uptake of some nutrients. The results showed that, the doses of nitrogen fertilizer caused a high significant increase in what grains and straw yield, where the highest mean values were 3.090 and 2.853 ton/fed. for grain yield and 4.305 and 3.893 ton/fed. for straw yield with two wheat varieties Sakha 69 and Giza 155 respectively with inoculation mycorrhizal fungi. Nitrogen fertilizer had also affected positively nitrogen uptake by wheat grain and straw. The highest mean values 43.49 and 44.73 kg N/fed. for grain and 15.79 and 14.01 kg N/fed. for straw yield with variety Sakha 69 and Giza 155, respectively, with inoculation. N-fertilizer as three doses increased significantly P-uptake by wheat grains and straw. The highest mean values (12.01 and 11.90 kg/fed.) for grain and (4.85 and 4.21 kg/fed.) for straw with variety Sakha 69 and Giza 155 respectively were found, with inoculation with mycorrhizal fungi. Potassium uptake increase by increasing doses of N-fertilizer. The highest mean values of K-uptake (14.06 and 11.41 kg/fed.) for grain and (55.79 and 50.27 kg/fed.) for straw yield were found with variety Sakha 69 and Giza 155 respectively, with mycorrhizal inoculation. The significant effect of inoculation with mycorrhizal was indicated by increasing the nitrogen, phosphorus and potassium uptake by grain and straw yields of wheat plants.