Pigeon Pea (Cajanus cajan)
Patricia Henderson
Colorado State University, Fort Collins, Colorado 80523
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1. OVERVIEW
Cajanus cajan, commonly referred to as pigeon pea, is the sixth most important edible legume crop globally. It is known for its adaptability and quick growth (Abebe, 2022). While mainly grown in semi-arid tropical regions, pigeon peas do well in many types of soils, have a strong tolerance to drought, and are able to yield well even in less favorable conditions. Pigeon pea is one of the most underutilized legume crops, even with its benefits of a significant level of nutrients and strong medicinal properties.
Pigeon pea is a short-lived perennial, most often grown as an annual. It has a deep root network well adapted to semi-arid conditions. Plants can grow to a height of 3 to 10 feet, with slender leaves, yellow or red flowers, and pods of various colors (CGIAR Genebank Platform, 2019). Their seed pods are long with two to nine large seeds (Rana & Kaushik, 2018).
2. HISTORY
It is generally agreed that pigeon peas originated in India (Upadhyaya et al., 2013). The CGIAR Genebank Platform (2019) states that the crop was domesticated there about 3500 years ago, later reaching Africa, where it spread rapidly. It was further spread to the Americas through the African slave trade (CGIAR Genebank Platform, 2019).
3. PRODUCTION AND USE
Pigeon peas are the sixth largest grain legume crop globally in terms of cultivated area and production (Emefiene et al., 2014). Currently, the largest producers of pigeon pea are India (70% of the total area), Myanmar, Malawi, Tanzania, and Kenya, aligning with the crop’s strong tolerance to hot and semi-arid conditions.
Pigeon pea, while an often-underutilized crop, is excellent at maintaining a reasonable crop yield with less than optimal environmental conditions. It has properties like drought tolerance, nitrogen fixation, ability to reduce soil erosion, and adaptability to a range of soil types. Pigeon peas are fast growers in the right conditions and tend to be very adaptable to their environments (Abebe, 2022). Based on the climate conditions in which it is grown, the crop varies in maturation speed. In drier conditions, it matures faster, while in humid weather, maturity occurs later (Rana & Kaushik, 2018). Pigeon peas are sensitive to temperature levels and the amount of light they receive, making frost and low sun detrimental to maturation speed and pod development (Rana & Kaushik, 2018). As such, pigeon peas are most commonly found as a crop in tropical and subtropical areas with dry climates.
The entire plant is utilized in subsistence agricultural systems: as a human food (both green and mature peas), for animal feed (leaves, seeds, husks, and pod shells), and as a household fuel (dry stems) (Rana & Kaushik, 2018). It is also grown as a green manure fertilizer (CGIAR Genebank Platform, 2019). Pigeon peas are processed into products such as n