RESPONSE OF SOME SUGAR BEET VARIETIES TO COMBINATIONS OF NITROGEN AND BORON FERTILIZATION.

Two field experiments were conducted at Sakha Agricultural ResearchStation (Kafr El-Sheikh Governorate) during 2008/2009 and 2009/2010seasons to investigate the effect of combinations of N and B applications onyield and its components as well as quality characteristics of three sugar beetvarieties namely: Lola, Pleno and Farida. Nitrogen was added as broadcast,and boron as foliar application at levels (100 kg N/fed + zero B), (100 kgN/fed + 100 ppm B), and (100 kg N/fed + 150 ppm B).The obtain results showed that:1- Root fresh weight (kg), as well as root length and diameter (cm) weresignificantly improved in both seasons by adding 100 kg N/fed + 100 or 150ppm B. Treatment with 100 kg N/fed + 150 ppm B significantly increasedsucrose % by (4.5 and 3.9%), extraction sugar% by (6.2 and 6.0%), rootyield by (11.8 and 10.4%) and sugar yield by (18.7 and 16.7%) comparedwith (100 kg N/fed + zero B) treatment in both seasons, respectively.Impurities parameters (K, Na and α-amino N%), and Alkalinity coefficientwere significantly reduced by adding 100kg N+ 150ppm B in both seasons.2- Varieties were significantly different for all traits under this study. Faridavariety was superior for root fresh weight by (8.5 and 7.2%), root diameter(7.0 and 5.5%) and root yield by (5.6 and 4.6%) compared to Lola variety inthe 1st and 2nd seasons respectively, while Lola variety surpassed othervarieties in quality traits (sucrose%, extraction sugar%, and extractability %and recoverable sugar yield/fed) in both seasons.3- Applications of nitrogen combined with boron had significant effect onsucrose%, as well as root and sugar yields (t/ fed) for the studied varieties inboth seasons.4- We can recommend by use 100 kg N/fed combined with Boron at 100ppmto reduce juice impurities and increase the productivity of sugar beetvarieties.