The Present study was performed in the Department of Pathology, BAU, Mymensingh during the period from January to December 2004. The study was conducted to determine the occurrence and pathology of pullorum disease, fowl typhoid and salmonellosis (paratyphoid infection) in dead chickens at necropsy in Mymensingh district of Bangladesh. A total of 70 samples (liver, ovary and intestine) were collected for isolation of bacteria in different media, and identification was performed based on the staining, cultural and biochemical properties of Salmonella spp. Routine histopathological method was used for the detection of tissue level alterations in Salmonella infected cases. Grossly, in all the infected cases the liver was enlarged and congested and in few cases, liver discoloration with focal necrosis. Old raised hemorrhages in the caecal tonsil and congested deformed ova were other important findings. There was catarrhal inflammation in the intestine. Microscopically, the section of livers showed congestion, hemorrhages, focal necrosis with infiltration of mononuclear cells. The pulmonary lesions consisted of sero-fibrinous exudation with mononuclear cell infiltration. The intestinal mucosa exhibited congestion, hemorrhages and infiltration of plasma cells, heterophils and macrophages. . Out of 70 samples, 8 isolates were identified as Salmonella (11.42 %). Of them, five isolates were identified as Salmonella gallinarum, causative agent of fowl typhoid, one isolate was characterized as Salmonella pullorum, causative agent of pullorum disease and other two motile salmonella were identified as paratyphoid infection.

Potato extract (PE), corn extract (CE) and papaya extract (PAE) at concentrations of 25, 50 and 100 mL L-1-1 CE.

An experiment was carried out at the Biotechnology Laboratory of Bangladesh Sugarcane Research Institute (BSRI), Ishurdi, Pabna for the development of drought tolerant somaclones. Five sugarcane varieties viz. Isd 20, Isd 35, Isd 36, Isd 37 and Isd 38 were used as plant material. Unexpanded spindle leaf sheaths were used as explants in tissue culture. In the first culture, the MS medium (BM) was supplemented with 2,4-D (3 mgL-1) and coconut water (10 %) for callus induction. The callus was then sub-cultured on fresh BM with BAP (2.0 mgL-1) and Kinetin (1.0 mgL-1) for plantlet initiation (2nd culture). In the third culture, initiated plantlets were sub-cultured again on fresh BM contained NAA (5.0 mgL-1) for root development. In all cultures BM was supplemented with 0.0, 5.0, 7.5 and 10.0% poly ethylene glycol (PEG) and was semi solidified with 0.6% agar to select somaclone variant plantlets of sugarcane in vitro. In the first culture 100% explants initiated callus on medium supplemented with no PEG. Callus induction, proliferation and plantlet regeneration decreased with increased level of PEG. At 7.5% PEG, the callus induction was highest (80%) in varieties Isd 35 and Isd 38. Callus was induced but became reddish black and senescence within 40 days on BM supplemented with 10.0 % PEG. Both shoot and root production decreased with increased PEG level in the medium. At 7.5 % PEG in BM, the highest shoot number was in Isd 38 (5.5 per culture), root number (7.6 per shoot) and root length (1.2 cm) were in the variety Isd 38. The highest shoot length was in Isd 37 and Isd 38 (1.8 cm). Survival percentage of in vitro regenerated plantlets was 100 % during hardening in low cost polythene house and in establishment in the field. Keywords: Somaclone; sugarcane; drought stress; plantlet; in vitro DOI: http://dx.doi.org/10.3329/agric.v9i1-2.9475 The Agriculturists 2011; 9(1&2): 18-28

Protocorm like bodies (PLBs) derived from callus of Phalaenopsis utilized sucrose , maltose and sorbitol for their growth in vitro. These carbon sources affected differently and could control PLB growth . On sucrose supplemented medium a few PLBs produced plantlets and most others regenerated yellowish or greenish callus like body (CLB). Almost 80% of unrooted and 58% of rooted plantlets developed yellowish green CLB at the base of plantlets. On maltose supplemented medium, PLBs regenerated PLBs and a few plantlets. In subsequent culture, about 44% of unrooted and 24% of rooted plantlets initiated green PLBs at the base of cultured plantlets. On sorbitol supplemented medium, most of the PLBs developed plantlets and a few additional PLBs. Among the carbon sources tested, sorbitol supported plantlet development the best in vitro and proved to be the most suitable carbon source for plantlet initiation and development from PLB.

An experiment was carried out in Plant Tissue Culture Laboratory, Department of Crop Botany, Bangladesh Agricultural University, Mymensingh to investigate the effect of banana extract on micropropagation of  <i>Dendrobium</i> sp. var. Sonia orchid through PLBs. The experiment was conducted during July 2012 to October 2013. Half-Murashige and Skoog (1/2MS) medium were used as basal medium and the medium was supplemented with banana extract at 12.5, 25, 50, 100, and 200 ml L-1 with a control, where no banana extract was supplemented. The cultures were done in 100 ml conical flasks and maintain at 25°C with 30µ mol m-2 S-1 lighting provided by florescent tubes for 16 hours per day. Banana extract showed significant effect on growth and development of PLBs. Among the treatments, 100 ml L-1 banana extract enhanced new PLBs regeneration from explanted PLBs and growth and development of PLBs. Present research indicated that nutrient requirement for PLBs multiplication and plantlets growth of  Dendrobium orchid is quantitatively different in vitro. Finally, 100 ml L-1 and 25 ml L-1 of banana extract may be recommended as supplement into 1/2MS medium for PLBs multiplication and plantlet regeneration, respectively in vitro.The Agriculturists 2015; 13(1) 101-108