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Evaluating satellite water extraction indices, particularly for coastal environments, guarantees that satellite-derived water maps are as accurate and functional as possible, notwithstanding the unique complexities these areas present. Variability in salinity levels, intricate land-water boundaries, dynamic sediment loads, and tidal fluctuations often complicate coastal water mapping. Sandwip Island in Bangladesh is one of the most complex and dynamic coastal environments in the world and is our area of focus. Six water information extraction indices were evaluated: normalized-difference vegetation index (NDVI), modified normalized difference water index (MNDWI), automated water extraction index for built-up areas (AWEInsh) and shadows (AWEIsh), multi-band water index (MBWI), and normalized difference water index (NDWI), using Sandwip Island’s satellite Landsat imagery acquired in February 1990, 2000, 2010, and 2020. The results showed that NDWI performed the best based on the total area obtained and classification accuracy. NDWI was then used to assess the erosion and accretion dynamics of the island for the study period (1990–2020). In the period 1990–2000, the island saw significant erosion and accretion along its coastlines in all parts, while the 2000–2010 period indicated that the island eroded on all sides. However, the situation was totally opposite during 2010–2020. The results illustrated the best performance of the NDWI algorithm in mapping surface water in the complex and dynamic Sandwip coastal environment. Also, erosion and accretion change temporally and spatially on the island. While this study is confined to Sandwip Island in Bangladesh, the findings hold the potential for broader applicability in regions with comparable characteristics.

Good health and well-being require safe drinking water and improved sanitation facilities. Lack of access to drinking water and sanitation facilities poses serious health risks. There are few studies based on the NFHS-5 data in the literature. Therefore, the present study used the NFHS-5 data to investigate the spatial distribution of limited access to drinking water and sanitation facilities in India. The Stata version 14.1 software was used for statistical analysis and Arc Map 10.4 was used for spatial analysis. A binary logistic regression model was applied to investigate the association between dependent and independent variables. The prevalence of limited access to drinking water and sanitation facilities was higher in Madhya Pradesh (12.28%) and Manipur (22.65%), respectively. Besides, the spatial distribution of limited access to drinking water and sanitation facilities was spatially clustered among a few central and western Indian states. In the binary logistic regression, education, wealth index, and place of residence were significantly associated with limited drinking water and sanitation services. There is regional heterogeneity in drinking water and sanitation services. With this in mind, we suggest spatially optimized target-oriented policy measures in unprivileged areas. Improving the water distribution networks and construction of sanitation facilities is also recommended. HIGHLIGHTS The central Indian states have limited access to drinking water and sanitation facilities.; The time to fetch drinking water (>30 min) is highest in Madhya Pradesh.; Poor, less-educated rural households have limited access to safe drinking water.; Diarrhoea is more prevalent in rural areas than urban areas.;

Access to safe drinking water and sanitation are essential fundamental rights for every citizen of a country. It is an important indicator of quality of life. Inadequate access to WASH services harms children under five and adolescent girls. This study examines the status of WASH services in West Bengal. A comprehensive assessment of WASH services was conducted using data from the fifth round of the National Family Health Survey. Data were statistically analyzed using Stata V. 14.1 software. A multivariate ordinal logistic regression model was applied to examine the association between experimental and explanatory variables. Furthermore, adjusted odds ratios, significance levels, and confidence intervals were provided for each dummy variable. The study found that only 33.69% of households in West Bengal have access to improved sources of drinking water. Moreover, only 74.35% of households have access to hygienic sanitation facilities within their premises, while 14.60% still practice open defecation. However, urban, Pucca, and non-nuclear households have better access to clean water, sanitation, and hygiene. The study also reported that drainage facilities are lacking in the state. Finally, the study recommends some policy measures to improve the access of WASH services in the state. HIGHLIGHTS People in non-nuclear households in cities have better access to WASH services.; Kolkata is ranked top in combined WASH services.; Purulia is the worst-performing district in terms of WASH services.; West Bengal's rural residents continue to practice open defecation.; The prevalence of diarrhea among children is higher in rural areas.;

In Bangladesh respiratory illnesses are one of the leading risk factors for death and disability. Limited access to healthcare services, indoor and outdoor air pollution, large-scale use of smoking materials, allergens, and lack of awareness are among the known leading factors contributing to respiratory illness in Bangladesh. Key initiatives taken by the government to handle respiratory illnesses include, changing of respiratory health policy, building awareness, enhancing healthcare facility, and promoting prevention measures. Despite all these efforts, the number of individuals suffering from respiratory diseases has increased steadily during the recent years. This study aims at examining the distribution pattern of respiratory diseases over space and time using Geographic Information System, which is expected to contribute to the better understand of the factors contributing to respiratory illness development. To achieve the aims of the study two interviews were conducted among patients with respiratory sickness in the medicine and respiratory medicine units of Rajshahi Medical College Hospital between January and April of 2019 and 2020 following the guidelines provided by the Ethics Committee, Department of Geography and Environmental Studies, University of Rajshahi, Bangladesh (ethical approval reference number: 2018/08). Principal component extraction and spatial statistical analyses were performed to identify the key respiratory illnesses and their geographical distribution pattern respectively. The results indicate, during January–February the number of patients was a lot higher compared to March–April. The patients were hospitalized mainly due to four respiratory diseases (chronic obstructive pulmonary disease, asthma, pneumonia, and pulmonary hypertension). Geographical distribution pattern of respiratory disease cases also varied considerably between the years as well as months of the years. This information seems reasonable to elucidate the spatio-temporal distribution of respiratory disease and thus improve the existing prevention, control, and cure practices of respiratory illness of the study area. Approach used in this study to elicit spatio-temporal distribution of repertory disease can easily be implemented in other areas with similar geographical settings and patients’ illness information from hospital.

Heat stress is a major production constraint of wheat in South Asia, particularly in the Gangetic plains of India and Bangladesh. The leaf chlorophyll status is a key determinant for a high rate of photosynthesis under stress. The present experiments included 238 genotypes in 2016-2017 and 321 genotypes in 2017-2018 under optimum and under heat stress conditions. Subsequently, a set of 100 genotypes selected on basis of the heat susceptibility index was evaluated in 2018-2019 under heat stress conditions to study the relationship between important physiological traits and yield under stress. A significant correlation of soil plant analysis development (SPAD) value of the two upper leaves with stay-green trait and grain yield indicates the importance of chlorophyll content, both in flag and penultimate leaf, in maintaining leaf areas under greenness (LAUG) and grain yield under heat stress. The SPAD in the flag and penultimate leaf was responsible for 8.8% and 10.9%, respectively, of the variation in grain yield. For the stay-green trait, 8.4% and 7.2 % of the variation was governed by the SPAD value in the flag and penultimate leaf, respectively. These results suggest that, in addition to the flag leaf, the chlorophyll status of the penultimate leaf can be an important criterion for the selection of superior wheat genotypes under heat stress. The genotypes SW-139; SW 108; DWR-F8-35-9-1; NHP-F8-130; DWR-F8-3-1 that maintained a high chlorophyll content in the flag and penultimate leaf can be used further in breeding programmes addressing heat resistance in wheat.

Spot blotch (SB) caused by Bipolaris sorokiniana (teleomorph Cochliobolus sativus) is one of the devastating diseases of wheat in the warm and humid growing areas around the world. B. sorokiniana can infect leaves, stem, roots, rachis and seeds, and is able to produce toxins like helminthosporol and sorokinianin. No wheat variety is immune to SB; hence, an integrated disease management strategy is indispensable in disease prone areas. A range of fungicides, especially the triazole group, have shown good effects in reducing the disease, and crop-rotation, tillage and early sowing are among the favorable cultural management methods. Resistance is mostly quantitative, being governed by QTLs with minor effects, mapped on all the wheat chromosomes. Only four QTLs with major effects have been designated as Sb1 through Sb4. Despite, marker assisted breeding for SB resistance in wheat is scarce. Better understanding of wheat genome assemblies, functional genomics and cloning of resistance genes will further accelerate breeding for SB resistance in wheat.

More than three billion people worldwide suffer from iron deficiency associated anemia and an equal number people suffer from zinc deficiency. These conditions are more prevalent in Sub-Saharan Africa and South Asia. In developing countries, children under the age of five with stunted growth and pregnant or lactating women were found to be at high risk of zinc and iron deficiencies. Biofortification, defined as breeding to develop varieties of staple food crops whose grain contains higher levels of micronutrients such as iron and zinc, are one of the most promising, cost-effective and sustainable ways to improve the health in resource-poor households, particularly in rural areas where families consume some part of what they grow. Biofortification through conventional breeding in wheat, particularly for grain zinc and iron, have made significant contributions, transferring important genes and quantitative trait loci (QTLs) from wild and related species into cultivated wheat. Nonetheless, the quantitative, genetically complex nature of iron and zinc levels in wheat grain limits progress through conventional breeding, making it difficult to attain genetic gain both for yield and grain mineral concentrations. Wheat biofortification can be achieved by enhancing mineral uptake, source-to-sink translocation of minerals and their deposition into grains, and the bioavailability of the minerals. A number of QTLs with major and minor effects for those traits have been detected in wheat; introducing the most effective into breeding lines will increase grain zinc and iron concentrations. New approaches to achieve this include marker assisted selection and genomic selection. Faster breeding approaches need to be combined to simultaneously increase grain mineral content and yield in wheat breeding lines.

Heat stress is one of the major wheat (Triticum aestivum) production constraints in South Asia (SA), particularly in the Eastern Gangetic Plains (EGP) of India and Bangladesh. Malnutrition is also a severe problem among children and women in SA. Wheat varieties with high grain Zn/Fe are a sustainable, cost-effective solution in the fight against hidden hunger. Thirty wheat genotypes were characterised under the optimum temperature and heat stress conditions in 2016-2017 and 2017-2018 to study the response of the stress on the yield, physiological traits and grain Zn/Fe content. A significant genetic variation was observed for all the traits under the optimum temperature and stress conditions. The yield was reduced by an average of 59.5% under heat stress compared to that of the optimum temperature. A strong positive association of the canopy temperature depression (CTD) with the grain yield (GY) was observed under the heat stress. A negative correlation of the grain Zn/Fe with the yield was observed under the optimum temperature and heat stress conditions, while the association between the grain Zn and Fe was positive. The genotypes BRW 3723, BRW 3759, BRW 3797, BRW 160, HD 2967, HD 2640 were found to be heat-tolerant in both years. Among the tolerant genotypes, BRW 934, BRW 3807 and BRW 3804 showed a high zinc content and BRW 934, BRW 3797, BRW 3788 and BRW 3807 showed a high iron content, respectively. These genotypes can be explored in future breeding programmes to address the problem of nutritional deficiency.

Wheat blast (WB) caused by Magnaporthe oryzae pathotype Triticum (MoT) is an important fungal disease in tropical and subtropical wheat production regions. The disease was initially identified in Brazil in 1985, and it subsequently spread to some major wheat-producing areas of the country as well as several South American countries such as Bolivia, Paraguay, and Argentina. In recent years, WB has been introduced to Bangladesh and Zambia via international wheat trade, threatening wheat production in South Asia and Southern Africa with the possible further spreading in these two continents. Resistance source is mostly limited to 2NS carriers, which are being eroded by newly emerged MoT isolates, demonstrating an urgent need for identification and utilization of non-2NS resistance sources. Fungicides are also being heavily relied on to manage WB that resulted in increasing fungal resistance, which should be addressed by utilization of new fungicides or rotating different fungicides. Additionally, quarantine measures, cultural practices, non-fungicidal chemical treatment, disease forecasting, biocontrol etc., are also effective components of integrated WB management, which could be used in combination with varietal resistance and fungicides to obtain reasonable management of this disease.

Spot blotch (SB) disease causes significant yield loss in wheat production in the warm and humid regions of the eastern Gangetic plains (EGP) of South Asia (SA). Most of the cultivated varieties in the eastern part of SA are affected by SB under favorable climatic conditions. To understand the nature of SB resistance and map the underlying resistant loci effective in SA, two bi-parental mapping populations were evaluated for 3 years, i.e., 2013–2015 for the BARTAI × CIANO T79 population (denoted as BC) and 2014–2016 for the CASCABEL × CIANO T79 population (CC), at Varanasi, Uttar Pradesh, India. DArTSeq genotyping-by-sequencing (GBS) platform was used for genotyping of the populations. Distribution of disease reaction of genotypes in both populations was continuous, revealing the quantitative nature of resistance. Significant “genotype,” “year,” and “genotype × year” interactions for SB were observed. Linkage map with the genome coverage of 8,598.3 and 9,024.7 cM in the BC and CC population, respectively, was observed. Two quantitative trait loci (QTLs) were detected on chromosomes 1A and 4D in the BC population with an average contribution of 4.01 and 12.23% of the total phenotypic variation (PV), respectively. Seven stable QTLs were detected on chromosomes 1B, 5A, 5B, 6A, 7A, and 7B in the CC population explaining 2.89–10.32% of PV and collectively 39.91% of the total PV. The QTL detected at the distal end of 5A chromosome contributed 10.32% of the total PV. The QTLs on 6A and 7B in CC could be new, and the one on 5B may represent the Sb2 gene. These QTLs could be used in SB resistance cultivar development for SA.