Tilapia lake virus (TiLV) is an emerging pathogen in aquaculture, reportedly affecting farmed tilapia in 16 countries across multiple continents. Following an early warning in 2017 that TiLV might be widespread, we executed a surveillance programme on tilapia grow-out farms and hatcheries from 10 districts of Bangladesh in 2017 and 2019. Among farms experiencing unusual mortality, eight out of 11 farms tested positive for TiLV in 2017, and two out of seven tested positive in 2019. Investigation of asymptomatic broodstock collected from 16 tilapia hatcheries revealed that six hatcheries tested positive for TiLV. Representative samples subjected to histopathology confirmed pathognomonic lesions of syncytial hepatitis. We recovered three complete genomes of TiLV from infected fish, one from 2017 and two from 2019. Phylogenetic analyses based on both the concatenated coding sequences of 10 segments and only segment 1 consistently revealed that Bangladeshi TiLV isolates formed a unique cluster within Thai clade, suggesting a close genetic relation. In summary, this study revealed the circulation of TiLV in 10 farms and six hatcheries located in eight districts of Bangladesh. We recommend continuing TiLV-targeted Tilapia, which comprises more than 100 species, is the second-most important group of farmed fish worldwide, after carp, and is considered to be among the most significant fish species to meet the rising global demand for protein, vitamin and mineral sources (Amal et al., 2018; Ng & Romano, 2013). Tilapia is farmed in over 135 countries, with global production estimated at 6.5 million metric tons (MMT) (FAO, 2017a). In 2015, the top four producers were China (1.78 MMT), Indonesia (1.11 MMT), Egypt (0.88 MMT) and Bangladesh (0.32 MMT) (FAO, 2017a). Overall, Bangladesh ranks fifth in the world in aquaculture production (FAO, 2017a) and has a total annual fisheries production of 41.34 MMT, of which aquaculture contributes 56.44% (DOF, 2018). The country earns a significant amount of foreign exchange through exporting fish, shrimps and other aquatic animal products from the fisheries sector. In 2017-2018, Bangladesh earned USD 513 million by exporting nearly 68,940 t of fish and fishery products (DOF, 2018). For the last 10 years, the annual growth of the aquaculture sector averaged 5.43% (DOF, 2018). Moreover, tilapia makes up 10.62% of total production and ranks second in the country, after channel catfish (DoF, 2018). Shortly after the first report of a novel disease among tilapia in Ecuador (Ferguson et al., 2014), tilapia lake virus (TiLV) was discovered as a newly emerging virus that caused mass die-offs in tilapia in Israel (Eyngor et al., 2014). Molecular analyses indicated that the same virus, TiLV, was the causative agent of these unusual mortality events in

Experiment was laid out in Randomized Complete Block Design (RCBD) with three replications. In case of nitrogen the highest yield (29.99 t/ha) was recorded from N 3 and lowest (18.65 t/ha) from N 0. In case of spacing the highest yield (25.83 t/ha) was achieved from S 2 and lowest (23.0 t/ha) from S 1. For interaction effect, the highest yield (31.31 t/ha) was obtained from N 3 S 2 and lowest (16.79 t/ha) from N 0 S 1. The highest BCR value (3.88) was recorded from N 3 S 2 and lowest (2.1) from N 0 S 1. So, 150 kg/ha urea with spacing of 40 cm × 25 cm were best for growth and yield of lettuce.

Phosphorus is a poorly bioavailable macronutrient that is essential for crop growth and yield. Overuse of phosphorus fertilizers results in low phosphorus use efficiency (PUE), has serious environmental consequences and accelerates the depletion of phosphorus mineral reserves. It has become extremely challenging to improve PUE while preserving global food supplies and maintaining environmental sustainability. Molecular and genetic analyses have revealed the primary mechanisms of phosphorus uptake and utilization and their relationships to phosphorus transporters, regulators, root architecture, metabolic adaptations, quantitative trait loci, hormonal signaling and microRNA. The ability to improve PUE requires a transition from this knowledge of molecular mechanisms and plant architecture to practical strategies. These could include: i) the use of arbuscular mycorrhizal fungal symbioses for efficient phosphorus mining and uptake; ii) intercropping with suitable crop species to achieve phosphorus activation and mobilization in the soil; and iii) tissue-specific overexpression of homologous genes with advantageous agronomic properties for higher PUE along with breeding for phosphorus-efficient varieties and introgression of key quantitative trait loci. More effort is required to further dissect the mechanisms controlling phosphorus uptake and utilization within plants and provide new insight into the means to efficiently improve PUE.

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Fruits and vegetables are important sources of nutrients for mankind. Among the various fruits available in Bangladesh, mango occupies a vital place in the human nutrition for its delicious taste and higher nutritious value. In this study, five mango varieties, viz. Fazli, Amrupali, Langra, Gopalbogh and Misribogh, were tested to evaluate the quality of these mango varieties available in Northern Bangladesh. Physiochemical characteristics, including moisture, ash, total carbohydrates, total solids, total soluble solids (TSS), pH, acidity, total sugars and ascorbic acid contents were evaluated. The results showed that there were significant (p< 0.05) differences among mangoes of all varieties for physicochemical parameters. In case of proximate composition, the mango variety Amrupali showed the highest ash content (2.34±0.15) and fat content (1.18±0.13). Protein content (0.94±0.12) and total fiber (2.67%) content was shown to be the highest by Gopalbogh and Misribogh, respectively. The selected mango varieties contained TSS of 12.87~20.55oBrix, pH of 4.45~4.67, titrable acidity of 0.07~0.42%, reducing sugar of 8.40~15.43%, non-reducing sugar of 9.24~10.48%, and total sugarof 18.88~25.12%. The study findings would be helpful for the consumers, dietitian and industry policymakers.