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(Macrobrachium rosenbergii) culture with paddy 31.4% in Manikganj and 16.5-32.6% in Netrokona.
in a semi-saline coastal environment. While the The bacterial brown stripe pathogen was detected
fish and prawn were cultured in three different from 22 seed samples (73.3%) collected from three
combinations of (i) GIFT alone (T 1), (ii) GIFT and locations indicating that the pathogen is an
prawn in the 1:1 ratio (T 2), and (iii) prawn alone emerging threat to rice growers in Bangladesh. A.
(T 3) at a stocking density of 10,000/ha, seven avenae subsp. avenae was identified by various
different rice varieties, viz. HR-1, HR-14, methods, including colony morphology, pigment
BRRIdhan-23, BRRIdhan-23 (L), BRRIdhan-40, production on King's B and biochemical tests. The
BRRIdhan-41. Horkoz (local variety) were also virulence test revealed that the organism is
evaluated simultaneously for their yield pathogenic to rice and sweet corn. Furthermore,
performance. After 120 days of rearing, the GIFT the pathogen has hypersensitive response to non-
attained a higher average weight of 86.30 g in T 2, host tobacco and pepper plants. The study suggests
than that of 78.50 g in T 1. Average growth of that an effective control measures should be
prawn was almost similar in both T 3 (22.10 g) and designed in order to limit further spread of the
T 2 (22.30 g). Despite of the low recovery rate of pathogen.
both the GIFT (18% in T 1 and 22% in T 2) and
prawn (26.54% in T 1 and 37.0% in T 2), the total 392 HARUN, M.E.; ISLAM, M.K.; RAHMAN,
fish production was 141.30 kg/ha, 136 kg/ha A.J.M.M. (Bangladesh Rice Research Institute,
(GIFT, 94.93 kg and prawn, 40.89 kg) and 57.87 Gazipur); DIAZ, C. (Social Science Division, IRRI,
kg/ha in T 1, T 2, and T 3 respectively. Among the Los Banos, The Philippines) & RAHMAN, K.M.
rice varieties, BRRIdhan-23 resulted in the highest (Dept. of Economics, Jahangirnagar University,
yield of 5.09 t/ha, followed by BRRIdhan-41 (4.84 Savar, Dhaka). Productivity enhancement through
t/ha). However, the duration of paddy ripening was rice seed quality improvement practices. Bang. J.
90 days for HR-1 and HR-14, while that of 110- Life Sci., 2006, 18 (2), 113-119.
120 days were for other varieties.
A farmers' participatory research was conducted in
391 HAQUE, M.M.; RAHIM, M.A. (Dept. of Sreepur under Gazipur district to find out the
Microbiology, Bangladesh Jute Research Institute, possibility of enhancing rice yield through seed
Dhaka) NAHER, K. (Dept. of Genetics and Plant quality improvement. Study findings reveals that
Breeding, Bangladesh Agricultural University, 95% farmers practiced winnowing for selecting
Mymensingh). Acidovorax avenae Subspecies heavy seeds and 87% of them found to have taken
avenae: An Emerging Threat to Rice Growers in special care in drying seeds before sowing. Almost
Bangladesh. Bang. J. Microbiol., 2005, 22 (1), 37- 80% farmers reported to have taken special care in
40. harvesting a selected portion of the field for seed
and 97% of the farmers removed unfilled grains
Prevalence of Acidovorax avenae subsp. avenae, after harvest. Sixty two percent farmers used
the causal agent of bacterial brown stripe disease special storage like moika (earthen pot), polybag or
of rice, was studied using slide cassette holder fertilizer bag. Plants from clean seed plots found
method. Rice seed samples collected from the more vigorous and uniform than those of farmers'
farmers of three selected areas of Bangladesh. own managed seed plots. Using clean seeds also
Seedlings showing bacterial brown stripe significantly increased number of tillers and
symptoms ranged from 7.0-40.5% in Tangail, 11.5- panicles per hill. Sheath blight, Sheath rot, dead
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