Response of sugar beet genotypes to sowing dates, graded levels of major nutrients and time of harvest under tropical conditions
Loading...
Date
2013
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
UAS Dharwad
Abstract
Field experiments were conducted at ARS, Bailhongal during 2005-06 and 2006-07.
Sowing dates experiment comprised of 12 monthly dates (I FN) in main plot and two
genotypes in subplots laid out in split plot design. Nutrient management trial comprised of
three factors of N (60, 120 and 180 kg ha-1), P2O5 (30, 60 and 90 kg ha-1) and K2O (60, 90
and 120 kg ha-1) laid out in RBD with absolute control. Harvesting dates trial comprised of
three genotypes in main plot and six harvesting dates in subplot laid out in split plot design.
Higher tuber yield (105.77 t ha-1) was recorded when the crop was sown on October I
fortnight (FN) over the other sowing dates and it was on par with September I FN sown sugar
beet (102.47 t ha-1). Sowing of sugar beet in October I FN recorded significantly higher
sucrose content (18.75%) which was on par with September I FN (18.25%) and November I
FN (18.09%). Sugar beet sown in October and September I FN recorded significantly higher
net returns (Rs. 90122 and 86160 ha-1) and B:C ratio (3.45 and 3.34), respectively. Sowing of
Cauvery genotype recorded significantly higher sugar beet tuber yield (79.14 t ha-1) than
Indus genotype (73.42 t ha-1).
The combined application of N120 P2O5 60 K2O 90 and N120 P2O5 60 K2O 120 recorded
higher tuber yield (112.1 and 115.2 t ha-1, respectively) over other combinations.
Significantly higher sucrose content (20.54%) was obtained by applying 60:90:90 kg ha-1 of
N, P2O5 and K2O, respectively. Sucrose content decreased significantly with increasing N
levels from 60 (18.41%) to 180 (17.49%) kg ha-1. Whereas, sucrose content increased with
increasing K2O levels from 60 (17.47%) to 120 (18.46%) kg ha-1. Also increasing application
of P2O5 from 30 to 60 kg ha-1 increased the sucrose content. Impurities and sucrose content
are negatively correlated. Application of 120:60:90 kg N, P2O5 and K2O ha-1 recorded the
highest net returns (Rs. 103280 ha-1) and B:C ratio (4.31) and was on par with
120:60:120 kg N, P2O5 and K2O ha-1.
Sugar beet harvested on 5, 5½ and 6 months recorded significantly higher tuber yield
(100.4 – 106.1 t ha-1) and sucrose content (19.30, 18.94 and 18.77%, respectively) as
compared to sucrose content either in early harvesting 4½ month (18.48%) or delayed
harvesting at 6½ and 7 months (18.33 and 16.12%). Early harvesting at 4½ months reduced
the tuber yield drastically. Delayed harvesting upto 6½ months did not have any adverse
effect on quality. Cauvery genotype recorded significantly higher tuber yield (108.1 t ha-1),
net returns (Rs. 92129 ha-1) and B:C ratio (3.45) as compared to Indus (83.90 t ha-1, Rs.
63062 ha-1, 2.68, respectively) but on par with Interprice Brucille.