الفهرس 
Vegetative growth characters of rice cropOnly 14 pages are availabe for public view
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Abstract
Two field experiments were conducted in the Meet Louza Village, Mansoura Province, Dakahlia Governorate, Egypt. The first experiment to study the effect of N-fertilization, biofertilization and foliar spray of ’’2 % N + yeast’’ or yeast on rice (Oryza sativa L., c.v. Giza 178). The second experiment, was to study the residual effect of such treatments on a wheat crop (Triticum aestivum L. , c.v. Sakha 93) which succeeded the rice crop. Experiments were of a factorial randomized complete block in 3 replicates. Three factorial were involved, foliar spray 2 treatments spray with yeast 16 g L-1 and Spray with urea at 20 g N L-1 plus yeast 16 g L-1, soil N-fertilization as urea 4 treatments (1) no-N, (2) 50 %, (3) 75 % and (4) 100 % N-level for rice crop ( recommended rate = 60 kg N fed-1). For wheat crop, the rates were (1) no-N, (2) 12.5 %, (3) 18.75 % and (4) 25 % N-level (recommended rate= 75 kg N fed-1 and biofertilization 8 treatments involving inoculums of Azolla (Azl), Azospirillum (Azs), Azotobacter (Azt), and Cynobacreria (Cyn) as well as mixtures (Azl + Azs), (Azl + Azt) (Azs + Azt) and (Cyn + Azt) which take the same location with the same layout of the experimental field for the previous crop (rice). The most important finding for rice crop, the highest rice yields were obtained from’’2% N+ yeast’’ spray along with ’’cyn. + Azt.’’ coupled with 50 % N-level for grain yield or 100 % N-level for straw yield. Treating rice plants with ’’Azl.’’ + 100 % N level in combination with ’’2% N+ yeast’’ foliar spraying gave the highest values of N-uptake. The highest P and K uptake by grains were achieved by 50 % N-level with ’’Azl. + Azt.’’ or ’’Cyn. +Azt.’’with ’’2% N+ yeast’’ foliar application. Regarding wheat crop, the highest grain yields was obtained from yeast spray and ’’Azs.’’ + 25 % N-level, while the highest straw yields was obtained from yeast spray + ’’Azl. + Azs.’’ coupled with 18.75 % N-level. The highest N and P uptake were obtained with combination of yeast spray combined with 18.75 % N-level and ’’Azl. + Azs.’’. The combination of’’2% N+ yeast’’ spray with 18.75 % N-level and ’’Azs.’’ gave highest K-uptake by grains. The highest net return (4126 £.L.fed-1.) for rice resulted from combination of spray ’’2% N+ yeast’’ with 50 % N-level and ’’Cyn. + Azt.’’ inoculation. Also, the highest net return (£.L.3060 fed-1.) was obtained from wheat receiving 25 % N-level + inoculation with ’’Azs.’’ and ’’2% N+ yeast’’ foliar spray. The highest value of % N-recovery (61.66%) was achieved with combination of ’’Azl.+ Azs.’’ + 18.75 % N-level and biofertilization. It could be concluded that, inoculation with biofertilizer mixtures along with foliar spray with yeast + N-solution could be used along with application of 50 to 75 % of the recommended rate of N for rice and 25 % for wheat crops. Thus would save 25 to 50 % of N fertilizer requirement.