Beyond physical resistance : novel aspects of plant silicon defences against arthropod herbivores

Silicon (Si) fertilisation has received increasing recognition in recent years for ameliorating biotic stresses in plants, including damage by pest herbivores. Si defences are effective against chewing herbivores as silicification makes plants abrasive and tougher, whereas sap-feeding insects are thought to be less affected. There are still substantial knowledge gaps regarding the effects of Si on direct and indirect (i.e. whereby plants benefit from natural enemies of herbivores) plant defences against herbivorous arthropods. Moreover, it is unknown how anti-predator defences (e.g. morphological, behavioural, and immune defences) of herbivorous insects are affected when feeding on Si-rich diets nor whether Si mediates interactions (e.g. competition, facilitation) between herbivores of different feeding guilds. Using plants with contrasting capacity for Si accumulation (i.e. low, moderate, and high Si-accumulators) and pest herbivores from different feeding guilds (i.e. chewing, sap-feeding, and cell-content feeding), this work explores some novel facets of plant Si defences against herbivorous pests. Overall, this work examined some novel aspects of plant Si defences across different Si-accumulating plants against herbivorous pests belonging to different feeding guilds. Specifically, this work investigated (i) the magnitude and locality of Si induction in plants following insect herbivory (chapter 2); (ii) how Si impacts induced direct (chapters 2, 4, 5, and 6) and indirect (chapter 3) plant defences against herbivorous pests; (iii) the plant-mediated effects of Si on the anti-predator defences of insect herbivores (chapters 4 and 6); and (iv) the impacts of Si on plant-mediated interspecific interactions between chewing and sap-feeding insect herbivores (chapter 5). Taken together, this work underpins that Si fertilisation can augment direct and indirect plant defences against pest herbivores and could be a sustainable management strategy for chewing and cell-feeding herbivores. Si could also play a part in pest biocontrol by promoting natural enemy attraction and undermining the anti-predator defences of insect herbivores. In contrast, Si fertilisation could provide a competitive advantage to sap-feeding insects by diminishing the performance of co-occurring chewing insects. Potential areas of future research and the limitations of the current work are discussed

Despite constitutional guarantees, Bangladesh is failing to deliver adequate healthcare to rural citizens

Bangladesh’s Constitution indicates that health is a basic right, and that the government is responsible for ensuring citizens’ access to healthcare. Yet the current system is failing those living in rural areas, even though they make up the majority of the population. Mohammad Tarikul Islam discusses the structure of health services in rural areas and where main challenges lie

How does local government cope with disaster in Bangladesh?

Successful coordination is an essential ingredient for Disaster Management. In the first of a two article series on human interactions with environment in rural Bangladesh, Mohammad Tarikul Islam examines the coordination in the comprehensive disaster management approach in rural Bangladesh under the auspices of local government (Union Parishad) and potential impediments to this approach

Climate negotiations: how does Bangladesh fare?

Climate change is the most significant challenge of the century, as increasing evidence of its impacts and the human actions responsible for it become apparent. There is a growing concern across the world regarding attaining the consensus and commitment needed to take action for positioning climate change in a broader foreign policy context. Mohammad Tarikul Islam examines this from the Bangladesh perspective

In quest of justice: dispute resolution in rural Bangladesh

In the second of his two-part series on local government relief efforts in rural Bangladesh, Mohammad Tarikul Islam argues that the dispute resolution process is lacking in inclusivity - often backing those with privileged circumstances or with close links to politics and public institutions. He considers the efficacy of local government driven dispute resolution and calls for a fairer arbitration process at the local level

How can Bangladesh utilise human security for rural development?

For safeguarding human security in rural Bangladesh, people-centred development is at the core of discourse: focusing on self-reliance, community living, social justice, and participatory decision-making. Unfortunately, it is missing in the context of rural Bangladesh, writes Mohammad Tarikul Islam

Ethics Pops up, Economy Constrains: Ethical Dilemma of Tobacco Retailers in Selling Cigarette to Minors

The paper investigates whether there is any ethical dilemma for the retailers of tobacco products to sell cigarettes to minors or not. With the study of secondary data and primary data coming from 60 retailers and 20 experts from Khulna City, Dhaka City, and Savar, the research concludes that in addition to the focus on retailers, policy makers have to think about mass awareness, mass education, proper implementation of laws, and availability of tobacco products to minors in order to reduce smoking by minors. Though not spontaneous, around 80 percent retailers find it unethical to sell cigarette to minors who is now 37 percent of the total market with 16 percent growth rate per year. Keywords: Retailers, Ethics, Smoking, Minor Smoker, Tobacco Market, Banglades

Despite legislative and institutional arrangements, Bangladesh is struggling to improve environmental governance

Over the years Bangladesh has become seasoned in environmental management. However, enforcement of legislations across levels is lacking where attention must be paid. Mohammad Tarikul Islam highlights the underlying challenges ahead for environmental governance in Bangladesh, and where solutions might be found

Access to justice for marginalised rural victims across South Asia: issues and challenges

For many people across South Asia needing to resolve a dispute but without access to formal justice systems, informal mechanisms have long been the norm. But how do they work in Bangladesh, India, Nepal and Pakistan, and how can they improve to ensure greater access to justice for rural marginalised people to the informal, asks Mohammad Tarikul Islam (Jahangirnagar University, Bangladesh)

Micro-Finance for Women Empowerment: A Rural-Urban Analysis

This paper examined the micro-finance services towards empowerment of unprivileged women in the southwestern part of Bangladesh. A sample of 300 low profile unprivileged micro-finance service receiving women equally from rural and urban areas of Khulna district were surveyed during May, 2018. Data were collected on the usage and effectiveness of micro-finance services and were analyzed using STATA 12. Multiple regression model and descriptive statistics were used to interpret data. Economic empowerment, social empowerment, interpersonal empowerment and political empowerment were considered to measure women empowerment. The study found that proper use of microcredit, marital status of women, educational status of women and their husbands, personal income and their position in the family were the main determinants of women empowerment. Women empowerment score remained higher in urban areas than in rural areas. The availability of micro-finance services improved the status of unprivileged low profile suburban women in terms of income generation, saving mobilization, the creation of household assets and overall poverty reduction of rural women. Thus, microfinance has been a useful tool for women empowerment and economic development in both areas but more effective in urban areas.&nbsp