Aly, M.H ; M.Y Abou-Zeid and Amal K. M. Soudi( 2011). Improvement Of Sugar Beet Productivity And Quality By Plant Growth Promoting RhizobacteriaEgypt . J. of Appl. Sci., 26 (11) 2011 656-677
Abstract: This investigation was conducted for two growing successive seasons (2009 / 2010 and 2010 / 2011) in Sakha Research Station (Kafer El-Sheikh Governorate, Egypt). The study aimed at finding out the possibility of saving 2/3 of N, P recommended doses through seed inoculation with Azospirillum lipoferum and Bacillus megatherium var. phosphaticum (PGPR) by using two application methods (seed coationg and drench method) under different doses of nitrogen and phosphorus fertilizers on nitrogenase enzyme activity and population density of tested bacteria. Sugar beet yield and juice quality were also evaluated. Results revealed that inoculation with both biofertilizers led to stimulated the counts of tested microorganisms compared to the uninoculated plants in the two growth periods for the tested seasons. The maximum numbers of Azospirillum lipoferum and Bacillus megatherium were obtained using two application methods on inoculation with two tested bacteria (seed coating and drench method) + 2/3 N + 2/3 P of recommended fertilizer dose. Also, the same treatment a significant improvement in nitrogenase enzyme activity of rhizosphere of roots. Dealing with sugar beet yield and its components, data demonstrated that Top, roots and sugar yield significantly increased to the two factors, inoculation and inoculation method, and their interaction. The pronounced treatment was inoculation with both of tested bacteria using seed inoculation along with spray application + 2/3 N + + 2/3 P of recommended fertilizer dose, where the roots increased by 12.62 and 6.89 % over control in the first and second season, respectively.
Juice quality of sugar beet and Percentages of N, P, K and -αamino N in roots improved as a result of PGPR inoculation with two methods of inoculation. Meanwhile, Na% in roots significantly decreased. The obtained results draws attention to the importance of inoculating sugar beet with Bacillus megatherium and Azospirillum lipoferum which played promoting effect in maximizing sugar yield / fed. and minimizing the fertilizers costs and environmental pollution.
Keywords: (Sugar beet, Azospirillum lipoferum, Bacillus megatheriu var. phosphaticum, seed coating, spray method, PGPR. Juice quality, Nitrogenase enzyme activity.)
