Jahangirnagar University Journal of Biological Sciences 2019-06-06T14:36:28+00:00 Professor Abdul Jabber Howlader, Ph.D. Open Journal Systems Official journal of the Faculty of Biological Sciences, Jahangirnagar University, Savar, Dhaka-1342, Bangladesh Effect of irrigation salinity on the growth and yield of two Aus rice cultivars of Bangladesh 2019-06-06T14:36:28+00:00 Tahmina Khanam Nahid Akhtar MA Halim Feroza Hossain <p>The experiment was conducted to clarify the growth and yield response of two rice cultivars, BR55 and BR43 under salt stress. Six different concentrations of NaCl viz 50, 100, 150, 200, 250 and 300 mM and distilled water (control) were applied on the rice cultivars which were grown under pot culture condition. Growth parameters like plant height, tiller number, leaf number and leaf area were negatively affected by salinity in both cultivars. Salt stress caused a significant reduction in yield in both cultivars of rice. Growth reduction was higher in BR43 than in BR55.The reduction in yield and yield parameters were found to be lower in BR55 than those in BR43. The results obtained in the present study suggest that BR55 showed higher salt tolerance than in BR43.</p> <p>Jahangirnagar University J. Biol. Sci. <strong>7</strong>(2): 1-12, 2018 (December)</p> 2018-12-30T00:00:00+00:00 ##submission.copyrightStatement## Detection of pathogenic bacteria from raw, pasteurized and UHT milk available in the local market of Gazipur District 2019-06-06T14:36:22+00:00 Nazia Afrin SM Rokon Ud Doula Rasheda Yasmin Shilpi <p>The present study was undertaken with the aim of investigating the bacteriological quality of locally available raw, pasteurized and UHT milk in Gazipur District. A total 5 raw, pasteurized and UHT milk samples were collected during November to December 2016. All the pasteurized and UHT milk samples showed the total aerobic heterotrophic bacterial (TAHB) level above the standard acceptable range (i.e. &gt; 10<sup>4</sup> cfu/ml for pasteurized milk and &gt; 0 for UHT milk). Both Gram positive and Gram negative pathogenic bacteria viz. <em>Staphylococcus aureus</em>, <em>S. epidermidis</em>, <em>Bacillus </em>sp., <em>Pseudomonas </em>sp. and <em>Enterobacter </em>sp. were isolated from studied samples. API 20 E was used for confirmation of <em>Pseudomonas </em>sp. This study indicates that most of the pasteurized and UHT milk samples were not satisfactory in terms of public health standard. Therefore, care must be taken to avoid possible health risk in every step involving collection, transportation, storage and post pasteurization handing of raw milk.</p> <p>Jahangirnagar University J. Biol. Sci. <strong>7</strong>(2): 13-19, 2018 (December)</p> 2018-12-30T00:00:00+00:00 ##submission.copyrightStatement## Susceptibility of third instar larvae of Culex quinquefasciatus Say (Culicidae: Insecta) against some commercial organophosphate and pyrethroid insecticides 2019-06-06T14:36:16+00:00 Shirin Akhter Aney Saadia Ahmad Tahmina Akter Md Golam Mostafa <p>Eight commercial insecticides-chlorpyrifos, bifenithrin, fenitrothion, cypermethrin, deltamethrin, cyhalothrin, dimethoate and malathion under the brand name of Dursban 20 EC, Bifenithrin 20 EC, Sumithion 50 EC, Relothrin 10 EC, Marker 2.5 EC, Reeva 2.5 EC, Tafgar 40 EC and Hilthion 57 EC, respectively were tested in laboratory at room temperature to evaluate the effective level against 3<sup>rd </sup>instar larvae of <em>Culex quinquefasciatus </em>Say from Savar area of Dhaka. The LC<sub>50</sub> values for chlorpyrifos, bifenithrin, fenitrothion, cypermethrin, deltamethrin, cyhalothrin, dimethoate and malathion were 0.127, 297.474, 0.308, 0.327, 0.198, 0.189, 0.054 and 0.031 ppm respectively and their corresponding LC<sub>90</sub> values were found to be 0.984, 2582, 0.041, 3.298, 0.728, 1.705, 0.192 and 0.030 ppm respectively. The relative potency of these insecticides tested to the larvae was found in respect to their LC<sub>50</sub> values in the order of Hilthion 57 EC (malathion)&gt; Tafgar 40 EC (dimethoate)&gt; Dursban 20 EC (chlorpyrifos)&gt; Reeva 2.5 EC (cyhalothrin)&gt; Marker 2.5 EC (deltamethrin)&gt; Sumithion 50 EC (fenitrothion)&gt; Relothrin 10 EC (cypermethrin)&gt; Bifenithrin 20 EC. However, the relative potency of these insecticides tested to the larvae was found in respect to their LC<sub>90</sub> values in the order of Hilthion 57 EC (malathion)&gt; Sumithion 50 EC (fenitrothion)&gt; Marker 2.5 EC (deltamethrin)&gt; Dursban 20 EC (chlorpyrifos)&gt; Tafgar 40 EC (dimethoate)&gt; Reeva 2.5 EC (cyhalothrin)&gt; Relothrin 10 EC (cypermethrin)&gt; Bifenithrin 20 EC. Taken together, the insecticide-malathion (Hilthion 57 EC) was found to be the most effective against the third instar larvae of <em>Cx. quinquefasciatus </em>in Savar area.</p> <p>Jahangirnagar University J. Biol. Sci. <strong>7</strong>(2): 21-32, 2018 (December)</p> 2018-12-30T00:00:00+00:00 ##submission.copyrightStatement## Investigation on a Bangladeshi isolate Bacillus aryabhattai for promising biotechnological applications 2019-06-06T14:36:10+00:00 Mohammad Shahedur Rahman Rasheda Banu Ripa Moni Nazmul Islam Mastura Khatun Ruma Umme Salma Zohora <p>A new isolate was investigated from soil sample collected from Shahrasti upazilla of Chandpur district of Bangladesh. Based on the physico-chemical studies the strain was identified as gram positive Bacilli. Moleculer characterization of the strain was identified as <em>Bacillus aryabhattai </em>which is the first report in Bangladesh. The strain can survive in extreme conditions of salt, temperature and pH. This strain was further characterized and screened for the ability to produce useful enzymes. The optimum temperature for growth and production of these enzymes was within the temperature range 35<sup>o</sup>C to 40<sup>o</sup>C. The pH was found to be 7 for its growth and production of different enzymes when investigated over 48 h of incubation. The isolate produced various extracellular enzymes such as α-amylases, cellulases, β-glucosidases, lipases and proteases. The findings of this study provide useful information of the new strain that has potential biotechnological applications.</p> <p>Jahangirnagar University J. Biol. Sci. <strong>7</strong>(2): 33-45, 2018 (December)</p> 2018-12-30T00:00:00+00:00 ##submission.copyrightStatement## Checklist of Angiosperms extant in Mirpur area of Dhaka city 2019-06-06T14:36:03+00:00 Shayla Sharmin Shetu Saleh Ahammad Khan Sarder Nasir Uddin <p>This study has recognized the occurance of a total of 346 species of Angiosperms under 256 genera and 82 families and assessed their current status and distribution in Mirpur area of Dhaka district. Majority of these families, 68 (82.92%) consist of 255 species under 192 genera, belong to Magnoliopsida (dicotyledons), and the rest 14 (17.07%) comprise of 91 species under 64 genera to Liliopsida (monocotyledons). Asteraceae with 18 species is found to be the largest family in Magnoliopsida followed by Euphorbiaceae and Fabaceae consists of 17 species each; while Poaceae is recognized as the largest family with 41 species in Liliopsida followed by Cyperaceae with 19 species. <em>Ficus </em>of Moraceae and <em>Cyperus </em>of Cyperaceae, each consists of 6 species, are found to be the largest genera in Magnoliopsida and Liliopsida, respectively. Total 236 species have been recorded as herbs followed by 58 tree seedlings, 50 shrubs and 2 lianas. Scrub jungles harbouring a total of 90 species are found to be the most common habitat of Angiosperms in the area, which is followed by marginal lands, road sides, grasslands, lake banks, fallow lands, woodlands, river bank, and highland slope and wet lands. A total of 281 economically important species have been determined from the study area. The occurrence of two threatened species, <em>viz</em>. <em>Andrographis paniculata </em>(Burm.f.) Nees and <em>Rauvolfia serpentina </em>(L.) Benth. ex Kurz, listed in the Red Data Book of Bangladesh, is recognized to be Vulnerable (V) in the study area.</p> <p>Jahangirnagar University J. Biol. Sci. <strong>7</strong>(2): 47-64, 2018 (December)</p> 2018-12-30T00:00:00+00:00 ##submission.copyrightStatement## Insights into the bioactive compounds, antioxidant potential and TLC profiling of different extracts of Tomato plants 2019-06-06T14:35:57+00:00 Sium Ahmed Faisal Bin Rahman Shawon Ahmed Abdullah Mohammad Shohael <p>Tomato (<em>Solanum lycopersicum L</em>.) is a widely cultivated vegetable crop worldwide and its consumption is increasing day by day. The only edible part of tomato plant is its fruit. Therefore, the residual tomato plant parts are considered as waste after fruit collection despite some portion of it is used as livestock feed and in the production of fertilizer. Moreover, due to the consumption issue, much of the research is focused on tomato fruit rather than other plant parts. Bioactive compounds can be present in any part of the plant and can be isolated and recovered. Therefore, tomato plant may be useful as a source of bioactive compounds. Our study focuses on the phytochemical constituents and bioactive compounds that are present in different parts of the tomato plant that were being less studied before. Qualitative phytochemical tests were performed to identify the presence of different bioactive compounds. Saponins, tannins, glycosides, phenols, alkaloids, flavonoids and resins are present in significant amount. Total phenol, total flavonoids, total tannin, and total protein content were measured quantitatively. Leaf samples showed higher concentrations of bioactive compounds than roots and stem. Highest total phenol content (66.43 mg/g), total flavonoids content (28.00 mg/g), total tannin content (7.36 mg/g) and total protein content (26.55 mg/g) was found from the leaf water extract. DPPH scavenging assay was performed to find the antioxidant potential and positive results were found. Thin layer chromatography (TLC) was also employed to check the constituents. Our study found several spots for different samples and their retention factors (Rf) were evaluated.</p> <p>Jahangirnagar University J. Biol. Sci. <strong>7</strong>(2): 65-77, 2018 (December)</p> 2018-12-30T00:00:00+00:00 ##submission.copyrightStatement## Nutrient status of soil and regenerated Garjan (Dipterocarpus turbinatus Gaertn.) seedlings in Dulahazara Garjan Forest, Cox’s Bazar, Bangladesh 2019-06-06T14:35:52+00:00 MK Huda MAM Chowdhury <p>Soil: Plant nutrient status in naturally regenerated garjan (<em>Dipterocarpus turbinatus </em>Gaertn.) seedlings of 3, 9, 15, 21, 27 and 33 months old were studied in twelve stands of three sites on late and early monsoon during 1994 to 1995 in Dulahazara garjan forest of Cox’s Bazar forest division. Soil samples were collected from two profiles (i.e. top soil and sub soil) of twelve stands in three sites. Soil moisture content, pH, texture, electrical conductivity, cation exchange capacity, organic carbon, total N and available P, K, Ca, Mg, Mn and Fe were determined. Soils were found to be silty loam to sandy loam with an average pH of 5.06. The average values of organic carbon and cation exchange capacity were 0.74% and 6.23 meq/100g respectively. The soils were poor in total nitrogen (689 μg g<sup>-1</sup>) and the average values of available mineral nutrients such as P, K, Ca, Mg, Mn and Fe in soil were 3.15, 53, 40, 47, 36 and 0.94 μg g<sup>-1</sup>, respectively. The soil in site -S2 appeared to be more fertile than those of site-S1 and site-S<sub>3</sub>. The average values of N, P, K, Ca, Mg, Mn and Fe in leaf- bud were found to be 1.80, 0.13, 0.94, 0.72, 0.23, 0.06 and 0.014% respectively. Leaf-bud nutrients showed a marked variation both with seasons as well as ages. Leaf-bud of late monsoon contained higher concentrations of P, Mg and Ca compared to leaf-bud of early monsoon which contained higher concentrations of N, K and Fe. Nutrient cycling in soil:leafbud system of regenerated garjan seedling of 3-33 months old varied with seasons and ages. The present study reveals that concentrations of Mn were significantly correlated between leaf-bud and soil whereas P showed the negative correlation indicating that in spite of low quantity of P in the soil, leaf bud had higher quantity.</p> <p>Jahangirnagar University J. Biol. Sci. <strong>7</strong>(2): 79-88, 2018 (December)</p> 2018-12-30T00:00:00+00:00 ##submission.copyrightStatement## Variability among selective guava (Psidium guajava L.) varieties revealed by morphology and RAPD marker 2019-06-06T14:35:46+00:00 Farzana Alam Kazi Didarul Islam SM Mahbubur Rahman <p>The research was conducted for the assessment of genetic diversity using both morphological and random amplified polymorphic DNA (RAPD) analysis of twelve guava (<em>Psidium guajava </em>L.) varieties growing in Bangladesh. Morphological characterization of guava varieties showed a wide range of variation. The highest variability was observed between Poly and Jelly varieties.Polymerase chain reaction with 5 arbitrary 10-mer and 3 arbitrary 12- mer RAPD primers produced a total of 50 bands of which 75.23 percent were polymorphic. The highest percentage of polymorphic loci (100%) was observed for primer A and the lowest (50%) for A03 primer. The UPGMA dendrogram revealed the segregation pattern and the difference of evolutionary changes. Guava varieties were separated into two main groups, one of them was made up of Chineese, Jelly, Kazi, Apple, L-49, Local-2 and Local-3. The other one was made up of Local-1, Poly, Kashi, Thai and Bombay. The highest genetic distance between Apple and Kazi peyara indicate that these varieties might be interesting in breeding programme for improving trait of interest. This scientific information could be used for further improvement of guava.</p> <p>Jahangirnagar University J. Biol. Sci. <strong>7</strong>(2): 89-98, 2018 (December)</p> 2018-12-30T00:00:00+00:00 ##submission.copyrightStatement## Bacteriological and ecfX- gene specific PCR based identification of Pseudomonas aeruginosa isolated from Chittagong industrial area and characterization of its extracellular amylase 2019-06-06T14:35:41+00:00 Asma Talukder Tanha Amina Mobashshera Istiaq Uddin Ahmed Nazneen Naher Islam <p>Amylases are the starch degrading enzymes with applications ranging from food, fermentation, textiles to paper industries. In this study, a soil bacterium from the Chittagong industrial area was screened primarily for amylase activity using starch agar media. An attempt has been made to isolate and identify this amylolytic bacterium, optimization of its amylase production and characterization of the crude enzyme. The isolate was identified as <em>Pseudomonas aeruginosa </em>based on microscopic and biochemical tests. Beside this a speciesspecific gene <em>ecfX </em>(146 bp) for <em>P. aeruginosa </em>was amplified by PCR to confirm the identification of the isolate. A broad range of parameters for the optimization of enzyme production based on selection of best carbon and nitrogen sources, optimum pH, temperature, incubation period and effect of additional metal ions on culture media were investigated. Best enzyme activity (343.60 U/mL) was found in the presence of glucose as carbon source with yeast extract as nitrogen source at temperature 37<sup>°</sup>C after 24h at pH 9 in addition of Mg<sup>++</sup> in submerged fermentation broth culture. The Mg<sup>++</sup>, SDS and Ca<sup>++ </sup>increased the amylase activity whereas EDTA and Zn<sup>++ </sup>were found as the inhibitory agents for amylase.</p> <p>Jahangirnagar University J. Biol. Sci. <strong>7</strong>(2): 99-114, 2018 (December)</p> 2018-12-30T00:00:00+00:00 ##submission.copyrightStatement## Rediscovery of Gonostegia Pentandra (Roxb.) Miq. (Urticaceae) from Bangladesh Sundarban 2019-06-06T14:35:35+00:00 Mohammad Sayedur Rahman Gazi Mosharof Hossain Saleh Ahammad Khan Sarder Nasir Uddin <p>Abstract not available</p> <p>Jahangirnagar University J. Biol. Sci. <strong>7</strong>(2): 115-119, 2018 (December)</p> 2018-12-30T00:00:00+00:00 ##submission.copyrightStatement## Rediscovery of Geophila repens (L.) I.M. Johnst. (Rubiaceae) in Bangladesh 2019-06-06T14:35:29+00:00 Robayda Khanam Saleh Ahammad Khan Abdur Rahim <p>Abstract not available</p> <p>Jahangirnagar University J. Biol. Sci. <strong>7</strong>(2): 121-125, 2018 (December)</p> 2018-12-30T00:00:00+00:00 ##submission.copyrightStatement##