OBIAL AND ENZYMATIC ACTIVITIES OF SOYBEAN EFFECT OF PLANT SPACING AND FOLIAR APPLICATION WITH BORON ON YIELD AND QUALITY OF TWO SUGAR BEET (Beta vulgaris, L.) VARITIES

Two field Experiment swore carried out at the Experimental Farm, Village of Tahnsha at Minia Governorate, Egypt , during 2014/2015 and 2015/2016 seasons, to study the effect of three plant spacings (15, 20 and 25 cm between hills) and foliar application of boron at three levels (control, 50 and 100 ppm) on yield and quality of two sugar beet varieties (Kawemira and Oscar poly). A randomize completed block design in split–split plot arrangement with three replications was used in the two seasons. Sugar beet varieties were assigned to the main plots, plant spacings were randomly distributed in the sub plots and boron levels were located in the sub –sub plots. The obtained results revealed that sugar beet varieties exhibited significant differences in root diameter (cm), top and root yields (ton /fad.) in both seasons, while root fresh weight (g/ plant), sugar yield (ton/fad.) and total soluble solids percentage (TSS%) in the first season only and sucrose percentage in the second season only . Root length (cm) wos not significant in both seasons. Plants of Kawemira variety were superior to Oscar poly variety in root diameter (cm), top, root and sugar yields /fad., total soluble solids percentage (TSS %) and sucrose percentage (%) in both seasons and root fresh weight/ plant in the first season only. Increasing plant spacing from 15 to 20 and 25 cm between hills resulted in a significant increase in root length (cm), root diameter (cm), root fresh weight/ plant, top, root and sugar yields /fad., total soluble solids percentage (TSS%) and sucrose percentage (%) in both seasons. Foliar application with boron significantly increased root length (cm), root diameter (cm), root fresh weight (g/ plant), top and root yields /fad. and total soluble solids percentage (TSS %) in both seasons, sugar yield/fad. in the first season only, and sucrose percentage in the second only. Boron level at 100 ppm gave the highest values for all studied parameters in the first and second seasons. In general, the highest of yield and quality were obtained from sowing sugar beet Kawemira variety af plant spacing 25 cm between hills and boron foliar application of 100 ppm under Minia Governorate conditions.