| dc.description | Rice (Oryza sativa L.) being one of the most cultivated cereals in all over the world
(Golshani et al., 2010) and the demand for rice will increase dramatically because of
the steady increase in population (Liu et al., 2012). Crop intensification and higher
yields are the only way to bridge the increasing gap between food production and
consumption in densely populated tropical Asia, because there is little new land
available for rice cultivation (Chauhan et al., 1985). It provides about 35-59% calories
for 2.7 billion people in Asia (Neue, 1993). In Bangladesh, a total of 11.61 million
hectares (Aus-1.2 million ha, Aman-5.63 million ha. and Boro-4.78 million ha.) of
lands are used for rice cultivation, which produced 34.75 million tons of rice (2.75
million tons Aus, 13.30 million tons Aman and 18.70 million tons Boro) in the fiscal
year of 2011-2012 (BBS and MOA, 2012). The rapid increase in population was
exerting tremendous pressure on producing more and more food grains. To meet up
the increasing demand for food grains, greater emphasis is being given to increase
grain production. This can be done by extending the rice cropping area or by
increasing yield ha’'. But the scope for extension of rice cropping area is limited and
therefore increasing yield ha’ is the only alternative. The average yield of rice in
Bangladesh is around 3.43 t ha! which is much below as compared to the highest
ranking country ( 10.29 t ha!) demonstrated like in Australia (FAO, 2004). The
increase in rice yield may be achieved by using improved variety, balanced
fertilization in association with some plant protection measures, adequate irrigation
and other improved practices. Introduction of modern high yielding varieties fertilized
with high rates of nitrogen has pushed the yield of rice but creating an imbalanced
nutrient status in the soil. | en_US |
| dc.description.abstract | A study was conducted to investigate the effect of different levels of phosphorus
fertilizer on the availability of soil phosphorus and T-aman (cv. BINA dhan7) yield
during kharif-2 season of 2012 at three locations (L;: Kunder Ali, Sadar, Panchagarh,
L,: HSTU, Dinajpur and L;: Palashbari, Parbatipur, Dinajpur). The experiment was
designed with six treatments in three locations and laid out in a Randomized Complete
Block Design (RCBD) with three replications. The treatments were, To: control (0 kg),
T,: 25 kg, Tp: 50 kg, T3: 75 kg, Ty: 100 kg and Ts: 37.5 kg ha’' TSP was applied. The
optimum rate of P fertilizer application needs to be determined on the basis of
available P in the soil and also P requirement and utilization efficiency of the crop.
The yield of rice was significantly varied with different treatments in three locations.
The yield contributing characters such as tillers hill’, grains panicle” and yield hill’
varied significantly with different levels of P. The highest grain yield 2.86, 6.55 and
4.80 t ha’'was found in T; treatment at location L,, L2 and Ls, respectively. The highest
straw yield was recorded 7.96, 9.22 and 8.02 t ha’ also in Ts treatment at location L,,
L, and L;, respectively. The lowest grain and straw yield t ha’ were recorded in
control at three locations. The grain and straw yield due to different treatments ranked
in the order of Ts> T,>T3> T2>T)>Tpo and in three location it was L.>L3>L). Soil test
basis (STB) fertilizer application showed maximum feedback. The chlorophyll,
protein, N, P, K, Ca, Mg, S, Zn, B, Cu, Fe and Mn content of flag leaves due to
different levels of P were markedly different and were highly significant among three
locations. More or less similar trend was also observed in yield contributing
characters, i.e., tillers hill, grains panicle’ and yield hill’. The available soil P and Ca
showed significant variation in different treatments. The soil OM, N, K, S, Zn, Mg,
Cu, Fe and Mn was increased but B was decreased due to different P levels in the
different stages of rice growth period than initial soil. The soil pH was changed at
different growth stages of rice due to dolomite application. The nutrient elements of
soil varied significantly in the three locations and at different growth stages of BINA
dhan7 rice. Based on different parameters studied, soil test basis fertilizer can be
recommended for higher yield as well as the farmers practice. | en_US |
