Regeneration ability of five Nicotiana varieties viz., Virginia, Jati, Motihari, CC Bengal and Sumatra were investigated via callus induction using leaf discs. Explants were cultured on MS medium supplemented with different concentrations and combinations of plant growth regulators. Callus formation frequency was 67.20%. Among the varieties used, Motihari induced the highest percentage (97.50%) of callus followed by Jati (92.50%) in 2.0 rng/L Kinetin and 2.0 mg/L IAA. Shoots were induced from calli cultured on the same medium. Maximum shoot formation from leaf discs was 82.50% on medium supplemented with 2.0 mg/L Kinetin and 2.0 mg/L IAA. It was also revealed from this study that Motihari was the best variety for callus formation and subsequent plantlet regeneration which is a pre-requisite for vector mediated transformation for varietal improvement of Nicotiana species. The rooting response of regenerated shoots was observed by using 1 / 2 MS medium with IBA (0.0, 0.5, and 1.0 mg/L). The highest root formation was found in Motihari (90%) with ½ MS medium supplemented with 0.5 mg/L IBA. After that regenerated plantlets with plenty of roots were transferred successfully to pots and subsequently to the field.

In this paper, students, and teachers' attitudes towards shifting to an entirely online learning environment were assessed due to COVID-19.  The main objective of the study was to investigate the students’ and teachers' attitudes towards Online learning during the COVID-19 situation in Bangladeshi Government Colleges. Findings revealed that cost and time-effectiveness, safety, convenience, and improved participation were the most frequently cited positive aspects of the online learning experience, while distraction and reduced focus, heavy workload, problems with technology and the internet, lack of ICT knowledge, and poor network infrastructure,  limited availability of educational resources, low attendance of learners, uncooperative learners and insufficient support from instructors and colleagues were the most recurrent negative aspects. The qualitative and quantitative research method was adopted, with semi-structured interviews conducted via Zoom with 10 College teachers and Focus group discussion conducted via Zoom with 18 and survey 100 college students via Google platform from three Bangladesh renowned Government College from Hons 1st year to masters’ level located in Rajshahi divisional district town of the country. A sample of these essays was analyzed using open coding. The findings of the study help instructors and institutions understand students’ and Teachers' attitudes regarding online teaching & learning under abnormal circumstances. Several recommendations informed by the interpretation of the participants’ feedback are offered to assist instructors, administrators, and policymakers improve future online learning experiences.  After conducting the whole study, it can be said that though have some problems adapting to online classes in three regarding BGCs colleges affiliated to the National University of Bangladesh, they are slowly becoming accustomed to it.

Anther of five varieties of Brassica species, namely BARI Shariaha-7, Tori-7, Agrani, Daulat and Safal were cultured in vitro to observe their regeneration potentiality. Different concentrations and combinations of growth regulators were supplemented in MS medium. The range of callus induction was 12.50-87.50 %. Maximum callus induction (75.00%) was observed on MS +4 mg/L 2, 4-D + 1.0 mg/L BAP. Among the genotypes, BARI Sharisha-7 showed the highest percentage of callus induction (60.42%). Among the treatments, highest percentage of shoot regeneration (75.00%) was observed on MS + 4 mg/L BAP + 1.0 mg/L NAA. BARI Sharisha-7 also showed the highest rate of plant regeneration (66.67%). Root induction was highest (75%) on half strength MS medium supplemented with 1.0 mg/L IBA and 0.5 mg/L NAA. The plantlets with sufficient roots thus obtained were transferred successfully to plastic pots and subsequently to the field. BARI Sharisha-7 and Tori-7 survived easily in the pots as well as in the field but Safal was very poor in survivability both in the pots and in the field. Key Words: Brassica; haploid; anther culture; in vitro regeneration.DOI: 10.3329/bjar.v34i4.5844Bangladesh J. Agril. Res. 34(4) : 693-703, December 2009

Three experiments were conducted with 60 germplasm accessions of yam (Dioscorea spp.) at Plant Genetic Resources Centre of BARI for characterization and conservation of germplasm. Fifty-nine germplasm accessions of D. alata L. and one accession of D. bulbifera L. from different  districts of Bangladesh were used. Clockwise twining direction was found in D. bulbifera and anti-clockwise twining direction was exhibited in all D. alata germplasm accessions. Potato like aerial tuber was found in D. bulbifera. Round, oval, elongate, flattened to irregular aerial tuber shape were found.  Grayed-brown, brown to grayed-orange skin colour with yellow, yellow-orange to grayed-orange of aerial tuber flesh colour were observed among the yam germplasm accessions. Oval-oblong, cylindrical, flattened, corm, rhizome to irregular shape of underground stem or tubers were observed. Low, medium to dense types of spiniess of roots were found on the tubers. Grayed-orange, red to black tuber skin colour along with white, yellowish-white, yellow, yelloworange, red to purple tuber flesh colours were found. Significant variations were also observed in stem shape at base, colour of stem, wing and petiole wing, position of leaf, leaf shape and distance between leaf lobes. Low to high phenotypic diversity was exhibited among the germplasm accessions. The germplasm accessions produced 1 to 30 under ground tubers per plant. The main tuber length ranged from 5.4 to 66.4 cm and breadth from 2.5 to 15.5 cm. The germplasm accessions produced 0.51 kg to 16.45 kg tuber yield per plant. The maximum variability was found in tuber yield per plant (98.74%) and the minimum was found in leaf length (12.55%).The under ground tubers of yam were harvested and replanted at an interval of two to three years from 1995 at PGRC. The plants were grown on bamboo trail in the field genebank. Necessary intercultural operations are done for maintaining the yam germplasm accessions. DOI: http://dx.doi.org/10.3329/bjar.v36i4.11748 Bangladesh J. Agril. Res. 36(4): 605-621, December 2011

Eggplant is an essential widespread year-round fruit vegetable. This study was conducted using 130 local germplasm of brinjal to select diverse parents based on the multiple traits selection index for the future breeding program. This selection was performed focusing on 14 qualitative and 10 quantitative traits variation and genetic parameters namely, phenotypic and genotypic variance (PV and GV) and genotypic and phenotypic coefficients of variation (GCV and PCV), broad-sense heritability (hBS), genetic advance, traits association, genotype by trait biplot (G × T), heatmap analysis and multi-trait index based on factor analysis and genotype-ideotype distance (MGIDI). Descriptive statistics and analysis of variance revealed a wide range of variability for morpho-physiological traits. Estimated hBS for all the measured traits ranged from 10.6% to 93%, indicating that all the traits were highly inheritable. Genetic variances were low to high for most morpho-physiological traits, indicating complex genetic architecture. Yield per plant was significantly correlated with fruit diameter, fruits per plant, percent fruits infestation by brinjal shoot and fruit borer, and fruit weight traits indicating that direct selection based on fruit number and fruit weight might be sufficient for improvement of other traits. The first two principal components (PCs) explained about 81.27% of the total variation among lines for 38 brinjal morpho-physiological traits. Genotype by trait (G×T) biplot revealed superior genotypes with combinations of favorable traits. The average genetic distance was 3.53, ranging from 0.25 to 20.01, indicating high levels of variability among the germplasm. The heat map was also used to know the relationship matrix among all the brinjal genotypes. MGIDI is an appropriate method of selection based on multiple trait information. Based on the fourteen qualitative and ten quantitative traits and evaluation of various genetic parameters, the germplasm G80, G54, G66, and G120 might be considered as best parents for the future breeding program for eggplant improvement.