| dc.description | Rice (Oryza Sativa L.) is one of the most important cereal crops of the world in
terms of food, area and production (Niamatullah et al., 2010). Bangladesh has the
highest population density as compared to any other country in the world, with 1015
living per square kilometer (BBS, 2011). So, rapid population growth puts increasing
pressure on more rice production in Asian countries (Liu et al., 2012). The
population of our country is increasing but the cultivable land is decreasing due to
urbanization and industrialization resulting in more shortage of food. Thus,
Bangladesh will require about 27.26 million tons of rice for the year 2020. Since it is
not possible to have horizontal expansion of rice area, rice yield should be increased
to meet this ever increasing demand of food. The rainfed Aus, the rainfed Aman and
irrigated Boro rice are cultivated in 10%, 51% and 39% in the total cropped area in
Bangladesh, respectively (BADC, 2008). But according to BBS Report 2008 Aus,
Aman and Boro produced 1.51, 9.66 and 17.76 million metric tons of rice. However,
Boro rice is one of the most important rice crops for Bangladesh with respect to its
high yield and contribution to rice production. National Commission of Agriculture
projected that to remain self-sufficient Bangladesh will need to produce 47 million
MT of paddy (31.6 million MT of rice) by the year 2020 (Chamely et al., 2015). | en_US |
| dc.description.abstract | A field experiment was conducted to study the effect of NAA (Naphthalene Acetic
Acid) on morpho-physiological, yield and yield combinations of HYV rice varieties
cv. BRRI dhan28. The study was performed during the period from February to
June, 2016 using 6 levels of Naphthalene Acetic Acid (NAA) such as 0, 25, 50, 75,
100, 125, ppm designated as T1, T2, T3, T4, T5 and T6 following 4 replications
designated as R1, R2, R3 and R4 respectively. The results showed that the
morphological, physiological, chemical properties of leaves, yield and yield
attributes were significantly influenced due to the levels of NAA. The plant height,
leaf number per plant, root number, root depth, flag leaf chlorophyll-a and
chlorophyll-b, total chlorophyll, total carotenoid content, protein content, Ca and Mg
content, panicle length, effective tiller, ineffective tiller, tiller number per plant,
grain number per panicle, grain yield, straw yield and biological yield were
increased markedly due to the application of NAA. The highest plant height, root
depth, number of tillers hill-1
, total chlorophyll content were obtained from 125 ppm
NAA spraying at seedling, vegetative and harvesting stages. The highest yield of
BRRI dhan28 cultivar was 4.49 (t ha-1
) due to the application of 125 ppm NAA
while other applied levels and controlled condition had less effect on the growth and
yield attributes. Plant growth regulator (NAA), promotes the growth and yield of
BRRI dhan28 which might be an alternative eco-friendly tool for rice production.
Out of six levels, 100 and 125 ppm performed better considering growth and yield
parameters. Therefore, it infers that the application with 100 ppm NAA had the
better stimulation and growth on yield of BRRI dhan28 in the study area. | en_US |
