Yield response of sugar beet to P rates (30 and 45 kg P2O5 /fed), N rates (60 and 90 kg N/fed) and timing of N application viz., all amount 0f N at sowing, split application in two equal doses, at sowing and at thinning or in three equal doses 1/3 at sowing + 1/3 at thinning + 1/3 one month after thinning. The main results obtained from this study revealed that:
- Application of 45 kg P2O5 /fed increased root size, in terms of length and diameter as well as root weight and produced the highest yield of roots, sugar and tops /fed, while juice quality traits (TSS, sucrose and purity %) were not affected by P rates.
- Increasing N rate up to 90 kg N/fed improved size and weight of the individual root and increased root yield by 3.4 tons, sugar yield by 460 kg and top yield by 1.41 ton/fed. On the other hand, higher N rate depressed beet quality.
- Split application of N in three equal doses improved size and weight of individual root and produced the highest yield of roots, sugar and tops/fed, while juice quality traits, in terms of sucrose and purity % were not affected by timing of N application.
- The interaction between P and N rates was significant with respect to root diameter, root weight and root yield/fed.
- The interaction between N rates and times of N application was significant with respect to length and weight of the root, TSS and top yield.
- The second order interaction had a significant effect on root weight.
The highest yields of roots and sugar /fed resulted from 45 kg P2O5 /fed + 90 kg N/fed applied in three equal doses 1/3 at sowing + 1/3 at thinning + 1/3 one month after thinning.