Agricultural Horizons: Research, Technology and Sustainable Development Vol. 7

A Conceptual Model Proposition for Understanding Rainfall-Soil-Crop Interactions in Dryland Taro Production

2026-11-10T07:19:20+00:00

Aims: To present an integrated conceptual framework linking rainfall variables, soil fertility characteristics, and crop traits for predicting taro yield and nutritional quality under dryland production systems.

Study Design: A narrative review chapter supported by previously published experimental studies and soil analytical data from South African dryland taro production systems.

Place and Duration of Study: The review used published data sources that focused on South African dryland agroecosystems, including field studies conducted on taro production systems.

Methodology: Literature was identified through searches of Web of Science, Scopus, Google Scholar and AGRICOLA databases between January and June 2026. Search terms included combinations of 'taro', 'Colocasia esculenta', 'rainfall', 'dryland agriculture', 'soil fertility', 'crop modelling', 'yield prediction', 'climate-smart agriculture', and 'nutritional quality'. Additional references were identified through citation tracking of key publications. Emphasis was placed on peer-reviewed studies published between 2000 and 2025.

Results: Soil acidity (pH 4.00-4.08), organic carbon (4.2-4.6%), phosphorus (12-15 mg L⁻¹), potassium (100-106 mg L⁻¹), clay content (51-55%), and propagule size were important determinants of taro establishment, growth, yield, and nutrient composition. Larger propagules produced greater yields and higher potassium and protein concentrations. Rainfall distribution emerged as a more important predictor than total seasonal rainfall. A conceptual climate-soil-crop framework was developed and expressed mathematically for future predictive applications.

Conclusion: Integrating rainfall, soil fertility indicators, and crop characteristics provides a promising foundation for developing climate-smart taro yield prediction systems that can improve productivity, nutritional quality, and resilience under dryland conditions.

Protecting Beneficial Arthropods in Modern Agriculture: Reconciling Pest Control with Pollination and Natural Enemy Conservation

2026-11-10T07:28:31+00:00

Modern crop production depends on suppressing damaging herbivores while retaining the insects and other arthropods that pollinate crops and regulate pest populations. Yet pest-control decisions, pesticide risk assessment and habitat interventions are often evaluated against separate ecological or agronomic objectives. This critical narrative review examines whether integrated pest and pollinator management can reconcile these objectives across cropping systems, distinguishing gains in beneficial arthropod abundance from demonstrated changes in ecosystem service delivery, marketable yield and economic return. Peer-reviewed field experiments, meta-analyses and mechanistic studies were appraised alongside evidence on pesticide exposure, landscape configuration and implementation constraints. The literature supports several robust propositions: diverse wild insects contribute substantially to crop pollination; resident predators and parasitoids can suppress pests; some diversification practices improve multiple ecological functions; and broad-spectrum or prophylactic insecticide exposure can undermine non-target arthropod performance. However, favourable responses in flower visitation or natural enemy abundance frequently fail to translate into reliable pest suppression or measurable yield gains. Outcomes differ with crop dependence on animal pollination, pest biology, habitat age and composition, the spatial and temporal organisation of fields, and pesticide exposure beyond treated crop boundaries. Contradictory landscape-scale findings caution against treating seminatural habitat as a universally sufficient intervention. An operational approach is therefore proposed that combines crop-specific economic thresholds, prevention-first pest management, exposure-aware intervention selection, habitat design for identified functional guilds, and joint monitoring of pest losses, pollination, biodiversity and profitability. Priority research needs include multi-season factorial field experiments, species-specific and mixture-sensitive risk assessment, economic evaluation, and tests across underrepresented tropical and smallholder systems. Reconciling pest control with beneficial arthropod conservation is feasible in some circumstances, but requires explicit attention to trade-offs and stronger causal evidence rather than assuming that ecological and productive benefits invariably coincide.

Beyond the Rational Farmer: Behavioural Biases and Technology Adoption in Agriculture

2026-11-10T07:33:46+00:00

Agricultural technology adoption is frequently explained through expected profitability, resource endowments and exposure to information. These explanations are indispensable, but they do not fully account for delayed input purchases, selective learning, heterogeneous responses to apparently identical risks or farmers' attachment to established practices. This critical narrative review examines how behavioural mechanisms interact with material constraints to shape the adoption, sustained use and abandonment of agricultural innovations. Literature published from 1985 to 24 August 2026 was considered, with earlier foundational decision-theory research retained where necessary. Evidence from agricultural economics, development economics, rural sociology, environmental psychology and field experimentation was evaluated by study design, construct measurement, causal identification, ecological validity and transferability. The synthesis distinguishes risk aversion from ambiguity aversion; present bias from seasonal liquidity shortages; informational deficits from selective attention; and social learning from conformity, trust and identity. Field experiments establish that adoption can respond to the timing of offers, credible reductions in downside risk and strategically targeted information. Yet observational studies and meta-analyses reveal marked heterogeneity across technologies, populations and settings, while several apparent psychological effects may represent rational responses to infrastructure, contractual insecurity and poorly measured opportunity costs. Behaviourally informed interventions are therefore best understood as complements to functioning input markets, insurance, extension, appropriate technology design and institutional accountability, not substitutes for them. The review proposes a conditional framework in which technology attributes, perceived consequences, decision architecture and structural feasibility jointly determine adoption trajectories. Priority research needs include pre-registered mechanism tests, repeated revealed-behaviour outcomes, cross-context replication, joint measurement of preferences and constraints, and assessment of distributional effects. Behavioural analysis can improve agricultural policy when it treats farmers as knowledgeable but situated decision-makers rather than presuming that non-adoption constitutes error.