Response of lettuce (Lactuca sativa L.) to salt stress

Lettuce is a highly nutritional crop that is sensitive to multiple stresses, including salt stress. The decreasing availability of salt-free water is posing a major challenge to growing nutritious lettuce in hydroponic systems. Despite evidence that salt stress affects yield and nutrition, its impacts on economically important growth stages are overlooked. This study addressed the knowledge gaps regarding the salt stress impact on romaine lettuce. Four independent experiments were conducted in controlled environment conditions using 2-38 lettuce genotypes, to assess the effects of salt stress at rosette or head formation. An increase in sodium chloride (NaCl) levels (0 to 150 mM) linearly decreased lettuce biomass. A positive association was observed between NaCl and sodium to potassium ion ratio. Lettuce was found to be sensitive to salt above 40 mM NaCl. The phenotyping of 38 lettuce genotypes revealed significant variability in salt stress tolerance. Genotype, Green forest exhibited a higher decline in fresh and dry biomass compared to Burgundy delight, indicating its higher sensitivity to salt stress. Sodium accumulation was significantly higher in both genotypes under salt stress, while potassium decreased in Green forest but remained relatively stable in Burgundy Delight. Hydro-primed lettuce had higher photosynthetic efficiency and oxidative stress tolerance than the control. Hydro-priming seed treatment could be used as a cost-effective priming technique to boost economic efficiency under stress. In addition, the low sodium: potassium ratio and high biomass can be used as indicators for selecting salt-tolerant genotypes

Building Capacities for Scaling-Up Climate Smart Village in Nepal: A training manual

Globally there has been enormous effort made by thousands of organizations to promote Climate Smart Agriculture (CSA) technologies for the sake of building resilience in agriculture and farmers’ livelihood. However, the progress so far is not satisfactory. Based on the past learnings CCAFS has conceptualized the idea of Climate Smart Village (CSV) which has CSA as the major component, along with other political and socio-economic dimensions. Looking at the successful piloting of CSV, the Government of Nepal has endorsed this approach in its program. However, a mechanism to share the idea of CSV to the development bodies is lacking. Similarly, the extension workers and other staffs of local governments do not have enough procedural understanding. Therefore, to scale-up CSV approach in Nepal, capacity building of government staffs and local leaders, especially at local and provincial level, is an absolute necessity. A guide book could be the means to facilitate the process of such capacity building. Hence this manual is developed as a guide book for organizing capacity building trainings to the government and non-government development professionals. It will also serve as a resource book to help development workers from local and provincial governments, local leaders, policy makers, researchers, and academicians to understand more about the idea and approach of CSV. Ultimately, this publication is expected to contribute to the mission of scaling-up the CSV approach for the enhanced resilience of farming communities in Nepal and around the world

A Review of Comparative Study on Solid Waste Management Practices in Four Different Cities in Asian Countries

Waste management is a grassroots level problem, and a decentralized and interdisciplinary approach is required to solve this problem. The exponentially growing population and the fast-changing socio-cultural behaviors of humans influencing mass production and consumption rates are not environmentally sustainable, and this explicitly defines the big picture in the solid waste management scenario. The emerging threat to the world is not only the alarming growth in the production of waste but also the unabating mismanagement of the waste we produce. This menace is troubling urban areas of both the developing and the developed nations with high population densities as waste management is often practiced as putting wastes away from immediate sight. After reviewing a few papers about the solid waste management practices around the world, it intrigued me to write how the best practices differ from the worst practices in waste management around Asian cities. In this paper, we assess solid waste management scenarios around four Asian cities and throw a light on the management practices that the best ones are doing differently to create a more sustainable urban environment for the residents. The countries that invest in a holistic evaluation of waste produced by their citizens and conduct proper research on how to manage wastes by utilizing locally available resources seem to perform better in the waste management sector

Water Corrosion and Scale Formation Problem and Its Solution in Water Supply Schemes – A Case Study on Padampokhari and Mahendranagar Scheme

The water with low total dissolved solid (TDS) and pH value is corrosive in nature. Moreover, the water with high TDS and low pH values is scale forming. A low TDS and pH value dissolves intake structures, GI pipes, concrete reservoir, household plumbing systems and cementing structures when it comes in contact with it. Furthermore, the corrosive water causes nuisance and health-related problems. Excess intake of lead, aluminum, copper, iron, chromium etc. in human body due to corrosive water causes serious damage to the different human organs such as brain, kidney, nervous system, blood cells, and even degrade an IQ level. High TDS and low pH value causes scale formation which blocks the whole water supply system. This paper presents a method for identification of corrosive and precipitative water and propose a solution to normalize it. The corrosive and scale forming water is detected easily by measuring a chief indicator parameter, TDS. The increasing value of TDS from intake to tap stand notifies that the water is corroding, and its decreasing values denotes the scale formation. Corrosive water is stabilized using calcium carbonate stones which is easily available in nature. On the other hand, scale forming water is controlled by the structural modifications of intake, collection tank, pipeline and reservoir etc. which we have constructed or going to construct. To verify the proposed methods, case study on Padampokhari and Mahendranager water supply schemes are studied and presented here in detail

Citrus Essential Oils: A Suite of Insecticidal Compounds

Citrus essential oils (CEOs) and their constituent compounds are being reported to have multifarious activities. In this chapter an attempt is made to discuss the insecticidal activities, as well as CEO profile of different vegetative part of Citrus species and biocidal potentiality of their constituent compounds against diverse insect pests. It is observed that in most of the CEO constituent profile, limonene is the major constituent compound. Other important constituents present in different percentages in different CEOs are β-citronellal, linalool, pinene, β- caryophyllene, β-myrcene, terpinene, citral etc. These plant EO constituents are reported to have insecticidal effects against diverse insect species. Taking the four peel EOs of Citrus limon, Citrus paradisi, Citrus medica, Citrus maxima commonly grown in North Eastern part of India, study on their insecticidal effects against Dolichoderus affinis (Hymenoptera: Formicidae) was made and result is presented showing higher fumigant toxicity of C. medica and C. limon oil against the ant sp. With the increasing awareness for using safe insecticidal products among consumers, the citrus EOs with their attracting terpene compounds having good insecticidal potency bear all attributes to be used as commercial green pesticides in coming days both in indoor and outdoor management of insect pests

Studying the Performance and Kinetic Values for Pollutant Removal Using Lab Scale Plant

The present study aimed at determining performance and pollutant removal kinetics in the treatment of wastewater using a laboratory-scale continuous flow stirred tank reactor (CFSTR) based on activated sludge process (ASP). The waste activated sludge from the Guheshwori Wastewater Treatment Plant (WWTP) is used as a start-up seed sludge. The CFSTR is operated at varying solid retention time (SRT) of 1, 2, 3, 5, 7.5 and 10 days using synthetic wastewater prepared daily as an influent. Chemical Oxygen Demand (COD) and Total Kjeldahl Nitrogen (TKN) of the influent, effluent and Mixed Liquor Volatile Suspended Solids (MLVSS) of aeration tank are analyzed at various SRT to determine the respective kinetic coefficients. The COD and TKN removal increased with increasing SRT. The kinetic coefficients; maximum substrate utilization rate (k), the half velocity constant (Ks), cell yield coefficient (Y ) and decay coefficient (kd) have been found to be 1.61 g COD/g VSS · day, 87.22 mg/L, 0.50 g Volatile Suspended Solid (VSS)/g COD and 0.07 day-1 respectively for synthetic wastewater. Similarly, k, Ks, Y and kd for the treatment of wastewater from Guheswori WWTP have been observed to be 1.86 g COD/g VSS.day, 107.77 mg/L, 0.32 g VSS/g COD and 0.04 day-1

Water quality index and human health risk assessment for heavy metals in groundwater of Bedkot Municipality, Kanchanpur, Nepal: A cross-sectional study

This study assessed groundwater quality and associated human health risks in Bedkot Municipality, Nepal, where 68.6% of households rely on tube wells (TWs). Twenty-three shallow TWs water samples (urban:10, semi-urban:6, and rural:7) were analyzed for physiochemical parameters (pH, temperature, turbidity, electrical conductivity, total dissolved solids, total hardness, calcium, ammonium, nitrate, total iron (Fe), and total arsenic (As)), following standard methods and assessed using the water quality index (WQI) and USEPA’s human health risk assessment (HHRA). Results revealed slightly acidic freshwater, with hardness varying (hard to very hard: urban/semi-urban, and moderately hard to very hard: rural). WQI classified 80% of urban, 90% of semi-urban, and 100% of rural samples as “excellent” for drinking, with none deemed unsuitable (WQI > 300). However, health risks emerged: children in all areas faced non-carcinogenic risks (Hazard Index, HI: 1.5–6.31). Some urban adults also showed risks (HI: 0.73–2.98), whereas no such risks were identified for adults in semi-urban and rural areas (HI: 0.73–0.95). Carcinogenic risks from As ingestion were significant for children (7E-04– 2.5E-03) and adults (3.3E-04– 1.2E-03) in urban, as well as children (7E-04– 9E-04) and adults (3.3E-04– 4.2E-04) in semi-urban and rural areas, exceeding acceptable thresholds (1E-06–1E-04). Children were 2.12 times more susceptible to non-carcinogenic and carcinogenic health risks than adults. These findings can guide sustainable groundwater quality management strategies in the region

Seasonal dynamics of lettuce growth on different electrical conductivity under a nutrient film technique hydroponic system

Lettuce, a staple in worldwide agriculture, has gained widespread acclaim for its adaptability and growing efficiency in hydroponic systems, demonstrating rapid growth cycles and economic significance. Electrical conductivity impacts the growth and physiology of lettuce cultivated under hydroponics. Maintaining the appropriate EC level during the lettuce growth cycle is critical for optimizing hydroponics practices. The greenhouse experiment examined the response of the 'Cegolaine Bibb' lettuce variety in a nutrient film technique hydroponic system throughout three seasons (summer, winter, and spring). The findings revealed significant physiological responses to varying EC levels. Stomatal conductance (gs) consistently decreased with rising EC in lettuce grown in summer and spring, indicating plant adaptive mechanisms to varying EC levels. Contrarily, lettuce during winter showed an unexpected increase in gs with greater EC, implying a unique seasonal adaptation. Steady-state fluorescence followed a similar pattern, declining with increasing EC in summer and spring but improving in winter. Furthermore, leaf temperature fluctuations across EC levels remained moderate throughout the summer, indicating minimal influences on lettuce temperature regulation. Morphological features, particularly fresh mass (FM), demonstrated a consistent pattern of increased production with higher EC levels in winter and spring. In contrast, lower EC levels were related to decreased FM for all seasons. Overall, the study emphasizes the dynamic interrelationships of EC levels and seasonal fluctuations influencing lettuce physiology and morphology. These findings highlight the importance of considering these aspects when optimizing hydroponic environments for increased lettuce growth and yield across seasons

Mitigating and Preparing for Disasters at The Organizational Level: A Global Systematic Literature Review

Organizations play significant roles in society by providing goods and services and contributing to the economies of communities, globally. Amid the predicted increase in the frequency and impact of disasters, which will invariably lead to higher disaster costs, there is an urgent need to ameliorate disaster impact on society and organizations. Disaster mitigation and preparedness are strategies for stemming disaster impact and losses within organizations. Cognizant of the importance of disaster mitigation and preparedness, researchers have conducted a myriad of studies on both concepts at the organizational level. To advance knowledge on this topic, this study conducted a comprehensive systematic literature review by examining the global trends in disaster mitigation and preparedness research at the organizational level, identifying research gaps in methodological dimensions, and recommending future research topics based on gaps in the literature. The authors searched three databases—Web of Science, EBSCO-ProQuest, and ABIinform—for keywords related to the topic and conducted a reverse citation search of the identified studies from the initial search, resulting in a final list of 123 studies. The findings indicate that research on this topic is relatively young and tends to mostly occur in collaborative environments. Additionally, most studies are quantitative and empirical in nature, and much of the research is on North America and Asia. Furthermore, while three-quarters of the studies do not specify a particular hazard type, among those that do, most focus on earthquakes and terrorist attacks in Asia and North America respectively, among other hazard types. This study concluded by recommending areas for future research