Production of Algal Growth Promoters And Studying Their Effects on Maize Crop

Abstract

Abstract

Plant growth promoters were estimated in three cyanobacterial strains (Anabaena azollae Strasburger, Spirulina platensis Geitler and Nostoc muscorum C. Agardh) in the presence of potassium nitrate, sodium chloride and tryptophan, with different concentrations (50, 100, 150 and 200 ppm) for both tryptophan and potassium nitrate, and (50, 100, 150 and 200 mmol) for NaCl, then the efficacy of these additives was estimated in terms of optimum concentrations of indole acetic acid and gibberellic acid production. Nitrogenase activity was estimated as well for the nitrogen fixing strains. A complete physical, chemical and biology analyses were made for the initial soil, and the results showed that the initial soil possesses sandy texture with EC (5.4 mS/ cm) and pH 7.6 and total nitrogen (53.38 μg/Kg). A field experiment was applied to Maize plant (Single White Hybrid 2031) that was planted in the Agricultural Research Center. Cyanobacterial treatments were applied three times throughout the cultivation period of the crop (Grain soaking, then ground application every 30 days). Mineral fertilization was applied according to the guidelines of the Egyptian Ministry of Agriculture, with 100% of the required nitrogen supply to control, and 75% to all other treatments. Final results showed that the highest yield was obtained by treating Maize with (Spirulina platensis with tryptophan, Anabaena azollae with both potassium nitrate and Anabaena azollae with tryptophan) respectively. Those results were almost three times more than the control yield. It was also found that the treatments (Anabaena azollae with NaCl), (Spirulina platensis with KNO3), (Nostoc muscorum with KNO3) and (Nostoc muscorum with tryptophan) improved the yield two times more than the control. So, from the mentioned results; it`s recommended for the yield improvement; to use the selected strains, especially in sandy and newly reclaimed soils.