Spirulina platensis is a protein rich cyanobacterium known for its remarkable nutritional profile, comprising essential amino acids, vitamins, minerals and health promoting bioactive compounds such as phycocyanin and carotenoids. These characteristics have led to its extensive use as a functional ingredient in human diets, animal nutrition, and aquaculture feeds. In fisheries, Spirulina enhances growth performance, immunity, reproduction, pigmentation, and overall health of cultured aquatic species. Beyond its nutritional applications, Spirulina platensis has emerged as a promising biotechnological resource due to its content of polyhydroxybutyrate (PHB), a biodegradable and biocompatible polymer. PHB offers potential for the development of sustainable and animal-free capsule shells as an alternative to conventional gelatin-based capsules. This article reviews the composition of Spirulina platensis, its importance in aquaculture, and its emerging role in the pharmaceutical industry as a source of eco-friendly capsule materials.

Salinity and alkalinity are major abiotic constraints limiting crop productivity, particularly in arid, semi-arid, irrigated and poorly drained environments. Excess soluble salts cause osmotic stress, ionic toxicity and oxidative damage, while sodicity and high soil pH impair soil structure and nutrient availability. Plants mitigate salt stress through osmotic adjustment, ion exclusion, vacuolar compartmentation, antioxidant defence and maintenance of ion homeostasis. However, intrinsic tolerance alone may be insufficient to sustain productivity under field conditions. Agronomic management therefore provides an essential complementary approach through improved drainage, leaching, efficient irrigation, soil amendments, salt-tolerant crops, appropriate planting methods, balanced nutrient management, seed priming and biological interventions. This review summarizes the major impacts of salinity and alkalinity on plants and evaluates key agronomic strategies for improving crop establishment, growth and productivity in salt-affected environments.

Climate-smart agriculture (CSA) seeks to improve agricultural productivity and incomes, strengthen resilience to climate change and reduce greenhouse-gas emissions where possible. Yet, technically suitable practices are not automatically adopted by smallholders. Adoption depends on labour, land, liquidity, information, credit, extension and the farmers? ability to absorb risk. The household resources shape the capacity to adopt, whereas the expected profitability, discount rates, crop choices and uncertainty shape the incentive to adopt. Low-cost and flexible practices often fit resource-constrained households better, while capital-intensive technologies may require suitable finance and markets. CSA should therefore be viewed as an investment decision under uncertainty rather than simply a behavioural choice.