Abstract:
The experiment was carried out at the Agronomy Field of the Sher-e-Bangla
Agricultural University, Dhaka during the period from December, 2006 to June, 2007
study the relative peribunance of inbred and hybrid rice varieties at difThrent levels of
phosphorus. Three varieties of inbred and hybrid rice (BRRI dhan 29, Moron and Hira-2)
and five levels of phosphoms(O. 24. 48. 72 and 96 Kg PnOs h15 were the treatment
variables. The experiment was laid out fellowing spilt plot design with three replications
having varieties in the main plot and phosphorus rate in the sub-plot. Plant height,
number
of
tillers bill
4
, fresh weight of plant, thy matter partitioning, total grains panicl&
'
-grain weight,
. spikelt sterility, 1000
grain yield, straw yield and harvest index varied significantly due to the variations of
.fihled grains panicle, unfilled grains panicle
4
variety. Hybrid variety Hira-2 produced the maximum number of filled grains panicleT'
(106.00) and minimum in BRRI dhan 29. Variety Hira-2 (7.50 t ha
d
) and Aloron (7.41
ha') produced the highest grain yields which were significantly different from BRRI
dhan 29 (6.86 t ha'). The yield increase due to variety Hira-2 and Moron was 0.64 and
0.55 t hi'. which was 9.32% and 8.0 l% respectively over BRRI dhan 29. All the studied
parameters of rice varieties except harvest index also differed significantly with the
application of phosphorus fertilizer. An application of 72 kg P205 hn' showed to
produced better yield attributes. Phosphorus level at 72 kg hi' (P3) produced the highest
grain yield (7.23 t haT') of rice. Plants grown without added phosphorus gore the lowest
grain yield (4.99 rhi'). A significant interaction between varieties and phosphorus levels
in respect of yield and yield attributes of rice was observed. Plants grown at any varieties
without P fertilizer produced lowest grain yield. Highest grain yield (7.68 t hi') was
recorded variety Hira-2 with 72 kg P
2
05 hi'. Number of efThctive tillers hilt', panicle
length, number of filled grains hill" and 1000-grain weight had a significant correlation
with grain yield t ha".