Abstract
Land degradation refers to the decline or loss of the biological or economic productivity of rainfed cropland, irrigated cropland, or range, pasture, forest, and woodlands caused by multiple factors, including land use and management practices. This degradation results in diminished agricultural productivity, increased poverty, hunger, and pollution, while exacerbating communities’ vulnerability to climate extremes and health risks. There is widespread concern that over 25% of the planet’s land is presently degraded, which has severe consequences for the general public, most notably smallholder farmers, rural residents, and the world’s impoverished populations. To address this challenge, feasible and localized interventions involving the contribution of socio-economically marginalised communities are required.
Agroforestry systems, which align with South Africa’s laws and policies aimed at preventing land degradation, are increasingly recognized as sustainable production approaches that strengthen climate change adaptation in semi-arid regions, such as Limpopo Province in South Africa. The integration of pigeon pea (Cajanus cajan), a drought-tolerant and high-value legume crop, into existing commercial lemon (Citrus limon) orchards offers a promising strategy to enhance and optimise resource use, climate resilience, and boost agricultural yields and income, in addition to improving the overall productivity of the smallholder farming system. This study evaluated the growth and yield responses of pigeon pea cultivated under different plant populations within young and early-mature lemon trees of a smallholder commercial farmer in the Limpopo province of South Africa.
The experiment was established in an existing lemon orchard under dryland, in a Randomised Complete Block Design in a split-plot arrangement with three replications. Main plots consist of lemon tree ages (10 months vs 33 months old), while subplots comprise three pigeon pea planting densities: high (45000 plants ha-1), medium (30000 plants ha-1), and low (22500 plants ha-1). Results from the study revealed that both lemon tree ages and pigeon pea densities significantly affected NDVI, plant height, and grain yield. The interface rows of pigeon pea consistently recorded the highest NDVI, pod length, and grain yield across tree ages and planting densities.
