الفهرس 
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Abstract
The present investigation aimed to evaluate the effects of planting
dates, plant populations, nitrogen fertilizer levels and limes of its splining
application as well as their interaction on sugar beet productivity under the
conditions of newly reclaimed sandy soils (at Kalabsho region in Northern.
Belkas district, Dakahlia Govemdrate), during the two successive growing
seasons of 1994 /95 and 1995 !96.
A split-split plot design with four replicates was used. Each planting
date was carried out as a separate experement and the combined analysis
was acheved. The main plots were devoted to the following four plant
populations:
Pj - 30000 plnnts / fad. (planting sugar beets on one side of ridges, 20 em
apart).
P2- 60000 plants / fad. (planting sugar beets on the two sides of ridges, 20
em apart).
PJ- 24000 plants / fad. (planting sugar beets on one side of ridges, 25 cm
apart).
P4- 48000 plants / fad. (plf1llting sugar beets on the two sides of ridges, 25
em apart).
While the sub plots were occupied by Ule three nitrogen fertilizer
levels:
N I - 60 kg N / fad.
N2 - 80 kg N / fad.
NJ - 100 kg N’! fad.
The sub-sub plots included three times of splilling nitrogen fertilizer
applications:
T j - Two equal portions (al 45 and 60 days after planting).
T2 - Three equal portions (at 45,60 and 75 days after planting).
T3 - Four equal portions (al45, 60, 15 and 90 days after planting)..
Each experimental unit contained five ridges, 70 em width and 6.0 m
long. occupi ng an area of 21.0 m2 (t 1200 fad).
The main results were summarized 1\S follows:
A- Effect of planting dates:
1- Growth aud yield components:
Planting sugar beets on first October resulted in marked increase in
number of leaves / plant. rOOl diameter, length and fresh weight (glplant),
foliage fresh weight, root / top ratio as well as harvest index in the two
seasons, The corresponding data recorded, 25.0 leaves! plant. 9, I em., 29.8
em, 523.9 g / plant, 293.0 g / plant, 1.78 and 0.637 respectively (as an
average of both seasons).
2- Yield quality:
The highest values of TSS % (23.82), sucrose % (18.34) over both
seasons and purity % (75.98 %) in the first season were recorded from
planting sugar beets on first September.
3- Yields (f / fad):
Planting sugar beets on first October recorded the max.imwn
averages of rool, top and sugar yields / fad. The corresponding averages
were \ 9.40, 1 1,22 and 3.44 t / fad respectively over the two seasons,
B- Effec(s of plant populations:
1- Growth and yield components:
Planting 24000 plants / fad gave the maximum values of number of
leaves / plant, rOOl diameter, root fresh weight, foliage fresh weight. root /
top ratio as well as harvest index in the lwo seasons. The corresponding
values were 25.9 leaves /plant, 9.4 em, 619.4 g / plant, 320.6 g / plant, 1.95
and 0.655 over both seasons respectively, while planting 60000 plants / fad
recorded the higest root length (30.1 cm) in the two seasons.
2- Yi£ld quality:
The lowest density (24000 plants / fad) recorded both the highest
total soluble solids % (25.11 %)andthehighestsucrose%(I8,9J %)over
the two seasons. While the highest density (60000 plants / fad) gave the
maximum purity (78 .13 %) over both seasons.