Australian Journal of Basic and Applied Sciences, 6(10): 664-674, 2012 ISSN 1991-8178 Corresponding Author: Sherif M. Ibrahim, Dept. of Soil Fertility and Microbiology, Desert Research Center, Cairo, Egypt. E-mail: amal_omaram@yahoo.com 664 Comparative Study of the Effects of Some Organic Extract on Sugar Beet Yield Under Saline Conditions Sherif M. Ibrahim, Heba, A.K. Ibrahim and Amal M. Omer Dept. of Soil Fertility and Microbiology, Desert Research Center, Cairo, Egypt. Abstract: A field experiment was conducted to study the effect of three different organic extracts; compost tea (C.T), fermented olive mill wastewater (OMWW) and Amino Green compound (A.A), as well as yeast on sugar beet yield (Beta vulgaris L.) cultivated in saline calcareous soil at Ras Sudr Experimental Station, South Sinai, Egypt, and irrigated with saline water (4.32 dS/m). Three application methods were used; foliar spray, soil drench and foliar spray with soil drench. Two treatments, with and without yeast (Saccharomyces cerevisiae) were added as soil drench. The results indicated that, the plots treated with the (A.A), (OMWW) or (C.T) significantly increased the yield of roots, leaves, sugar comparing with the untreated plots. The corresponding increment values were respectively 49.5%, 59.8% and 23.9%, for roots, 50.5%, 47.0% and 79.7% for leaves, and for sugar yield were 58.8%, 63.7% and 25.2%. Both of OMWW and A.A treatments significantly increased the yield of roots and sugar comparing with C.T. While, C.T. increased the yield of leaves comparing with A.A. or OMWW, regardless of application method or addition of yeast. Yeast treatments significantly increased the yield of roots, leaves, sugar and sucrose content, recording increments of 22.1%, 30.4%, 28.4% and 5%, respectively. The interaction effect between yeast and organic extracts on yields was non significant .The application methods as soil drench of OMWW and as foliar spray plus soil drench of A.A gave the highest values of roots yield. The C.T, A.A and OMWW treatments significantly increased soil nutrients availability of N, P, Fe, Mn, Zn and K, compared with the control. Microbiological analysis of sugar beet rhizosphere revealed that the highest counts of total microbes, yeast, fungi and actinomycetes were detected in plots treated with A.A, OMWW with yeast and A.A with yeast, respectively. It could be concluded that the highest significant increases in roots and sugar yields were obtained by using yeast integrated with the treatment of (soil + foliar application of A.A) or (soil application of OMWW).These organic fertilizers successfully reduced the hazard effect of soil salinity conditions. Key words: organic extracts amino acids, olive mill waste water, compost tea, yeast, sugar beet, saline condition, soil treatments. INTRODUCTION Sugar beet crop (Beta vulgaris L.) is considered to be the second source for sugar production in Egypt. It tolerates soil salinity and soil water stress (Hills et al., 1990). One third of the Egyptian cultivated lands are already salinized. Overcoming salt stress is a main issue in the arid and semi-arid regions to secure crop productivity (Ghassemi et al. 1995). Soil salinity is adversely affecting physiological and metabolic processes, finally diminishing growth and yield (Ashraf and Harris, 2004). Excessive salts injure plants by disturbing the uptake of water into roots and interfering with the uptake of competitive nutrients (David Franzen, 2007). The inhibitory effect of salinity on plant growth and yield has been ascribed to osmotic effect on water availability, ion toxicity, nutritional imbalance, reduction in enzymatic and photosynthetic efficiency and other physiological disorders (Khan et al., 1995). Saline calcareous soils are frequently characterized by the low bioavailability of plant nutrients. Among the nutrients in the soil, deficiency in nitrogen, phosphorus, potassium, zinc, iron, manganese have been identified as some major constraints in sugar beet crop production, should be added to the soil accordingly (Armin and Asgharipour, 2011). To overcome the problem of sugar production shortage in Egypt, the challenge must be inevitable for reliving salinity conditions. Nowadays, a great attention has been focused on the possibility of using natural and safe agents for promoting growth and yield of sugar beet under saline stress. The use of organics and microbial systems for nutrients mobilization, or as biofertilizers are getting popular in recent years and being introduced to cater for different cropping systems.