Pigeonpea [Cajanus cajan (L.) Millspaugh]

Pigeonpea is an often cross pollinated (20 – 70%) crop with diploid chromosome number 2n=2x=22, and genome size 1C = 858 Mbp.

Pigeonpea [Cajanus cajan (L.) Millspaugh] is a short-lived perennial shrub that is traditionally cultivated
as an annual crop in developing countries. It is an important legume crop mostly produced in Asia, Africa, Latin America, and the Caribbean region. Considering the vast natural genetic variability in local germplasm and the presence of numerous wild relatives, India is probably the primary center of origin of pigeonpea.

It is a hardy, widely adapted and drought tolerant crop with a large temporal variation (90 – 300 d) for maturity. These traits allow its cultivation in a range of environments and cropping systems. Globally, pigeonpea area has recorded a 56% increase in area since 1976. It is currently grown on 4.8 m ha. It is grown in Asia, Eastern and Southern Africa, Latin America and Caribbean countries. It is cultivated worldwide on 4.92 million hectares (M ha) with an annual production of 3.65 Mt and productivity of
898 kg ha^-1.

In Asia, India (3.58 M ha), Myanmar (560,000 ha), China (150,000 ha), and Nepal (20,703 ha) are major pigeonpea growing countries. On the African continent, Kenya (196,261 ha), Malawi (123,000 ha), Uganda (86,000 ha), Mozambique (85,000 ha), and Tanzania (68,000 ha) grow considerable quantities of pigeonpea. The Caribbean islands and some South American countries also have a considerable area devoted to growing pigeonpea.

Invariably, the traditional pigeonpea cultivars and landraces are long duration types grown as intercrops with other more early maturing cereals and legumes. In addition to its main use as de-hulled split peas, its immature green seeds and pods are also consumed fresh as a green vegetable. The crushed dry seeds are fed to animals while the green leaves form a quality fodder. In rural areas, dry stems of pigeonpea are used for fuel. In a cropping season, pigeonpea plants fix about 40 kg ha -1 atmospheric nitrogen and add valuable organic matter to the soil through fallen leaves. Its roots help in releasing soil-bound phosphorus to make it available for plant growth. With so many benefits at low cost, pigeonpea has become an ideal crop for sustainable agriculture systems in rain-dependent areas.

Asia

• In Asia, pigeonpea is grown in an area of 4.3 m ha and production of 3.3 m tons (Figure 1). India has the largest area (3.6 m ha) under pigeonpea, followed by Myanmar (560,000 ha), Kenya (196,000 ha), China (150,000 ha), Malawi (123,000 ha), Uganda (86,000 ha), Mozambique (84,000 ha), Tanzania (68,000 ha) and Nepal (21,000 ha).

• Maturity duration (at 17⁰N latitude) varies from about 90 days for extra-early varieties to more than
  260 days for long-duration varieties.

• Extra-short and short-duration pigeonpea varieties fit well in various cropping systems, providing greater crop diversity. One good example has been the adoption of ICPL 88039 (extra-short duration variety) in pigeonpea-wheat rotation in the rice-wheat cropping system in North-west India. It is also showing promise in rice fallows in lower latitudes.

• In Asia, between 1976 and 2006, pigeonpea recorded
• 56% increase in area (2.76 to 4.32 m ha)
• 54% increase in production (2.14 to 3.29 m t)

Figure 1. Three-year moving average for pigeonpea area, production, and yield; and number of varieties released (3-year total) based on ICRISAT-bred material in Asia.

Myanmar

Pigeonpea grown in Myanmar is mainly for export to India. Therefore, the production trends in Myanmar have a direct bearing on the domestic pigeonpea prices in India. Pigeonpea area in Myanmar has increased from 57,064 to 560,000 ha and production from 37,110 to 530,000 t between 1990 and 2006.
Five pigeonpea varieties, based on ICRISAT-bred material have been released in Myanmar.

China

Pigeonpea in southern China is primarily used for soil conservation, food and fodder. ICRISAT variety
ICP 7035 has shown high adaptation in different provinces. Currently, pigeonpea is grown on 150,000 ha
in Guangxi and Yunnan provinces.

Africa

In Eastern and Southern Africa (ESA), pigeonpea is grown on 0.56 m ha (Figure 2).

It is an important crop of Kenya, Malawi, Uganda, Mozambique and Tanzania.

Between1976 and 2006, pigeonpea recorded:

• 133% increase in area (0.24 m ha to 0.56 m ha).
• 178% increase in production (0.14 m t to 0.39 m t).

Figure 2. Three-year moving average for pigeonpea area, production, and yield; and number of varieties released (3-year total) based on ICRISAT-bred material in Eastern and Southern Africa.

• In Eastern Kenya, about 20% of the farmers have adopted new varieties. Farmers have also started adopting the medium duration pigoenpea varieties (ICEAP 00554 and 00557) both for grain purposes as well as green vegetable.

• In Tanzania, about 50% of the farmers in Babati district adopted new varieties and production area expanded beyond the traditional Babati district to reach the neighboring districts of Karatu and Mbulu. In some areas, farmers are adopting long duration, compact growth habit genotype (ICEAP 00053) in maize intercropping systems.

• The use of long duration, fusarium wilt resistant and consumer/market preferred variety (ICEAP 00040) in northern and central Tanzania, Kenya and Malawi resulted in increased grain yields and lowered production costs in comparison to local genotypes.

• NARS partners have released pigeonpea varieties in Malawi (4), Kenya (3), Tanzania (3), Uganda (2) and Mozambique (1).

Hybrid Technology

• ICRISAT and partners have developed the world’s first commercial cytoplasmic male-sterility (CMS) based hybrid in pigeonpea.

• CMS based hybrids in extra short, short and medium maturity groups have recorded grain yield superiority of 20-80% over the popular check varieties in different locations across India. This technology is also being transferred to China and Myanmar.

Cultivars Released

Fifty-seven cultivars based on improved germplasm developed by ICRISAT have been released in several countries of Asia (38), Africa (13) Australia (3) and USA (3). The short and medium-duration types and disease resistant cultivars have made a significant impact in Asian countries. However, long and medium duration varieties have generated a strong impact in Eastern and Southern Africa.