afrol News, 16 April - Nigeria has released two new cowpea varieties to raise production and improve farmers' incomes. The varieties were developed in Nigerian research institutions.

The new cowpea varieties are being presented as Nigerian researchers are finalising their plans to attend the Fifth World Cowpea Research Conference to be held from 27 September to 1 October in Dakar, Senegal, to discuss the state of the art in cowpea research.

The varieties - so far going under the technical names IT89KD-288 and IT89KD-391 - were developed by scientists working at four Nigerian universities and research centres. "Both varieties have proven superiority over the current improved lines being cultivated and aim to overcome the challenges faced by cowpea farmers in the country," according to researchers.

One of the newcomers is a dual-purpose cowpea variety with large white seeds and a rough seed coat. It has combined resistance to major diseases including septoria leaf spot, scab, and bacterial blight, as well as to nematodes, and tolerance to Nigeria's strain of Striga gesnerioides - a parasitic weed that severely lowers yield.

"It also has a yield advantage of at least 80 percent over the local varieties," said Dr Alpha Kamara, agronomist at the Ibadan-based the International Institute of Tropical Agriculture (IITA), who is leading efforts to rapidly disseminate the varieties to farmers.

The nematode-resistant variety was said to be "an equally good candidate for sowing in cereals or as a relay crop with maize in the moist and dry savannah zones, as well as for high grain production in the dry season."

Scientists recommend that the variety be planted in mid July in the Sudan savannah, early to mid-August in the northern Guinea savannah, and by the end of August in the southern Guinea savannah. However, where there is certainty of rains up till the end of October, the new variety could be planted in September.

The other newcomer is also a dual-purpose cowpea variety but it has medium-to-large brown seeds with a rough seed coat. These are preferred seed characteristics for commercial production in northeast Nigeria.

The new variety was said to be "a welcome improvement" over other cowpeas varieties earlier developed in and for Nigeria, now being the main improved brown-seeded varieties available in the country. "It has been tested extensively in this area and is well accepted by the farmers," said Dr Hakeem Ajeigbe, IITA dissemination specialist.

"The variety performs well as a sole crop and an intercrop. It could also be planted as a relay crop with maize in the Guinea savannas," he added.

Several on-station and on-farm trials have shown that new variety produces double the yields of local cultivars.

Nigeria has a major science community regarding cowpeas, being among the world's leading environments on that field. In 2008, Nigeria released the first workable Striga-resistant improved cowpea variety.

Currently, efforts are being made through the project on legumes funded by the Bill and Melinda Gates Foundation to make available seeds of these improved varieties by setting up community-based seed production schemes.

According to Dr Kamara, "The demand for these improved varieties is high because of their superior yields and their acceptability by consumers."

With about 70 percent of world cowpea grown in the savannah region of Africa, the protein-rich legume provides not only incomes but also improves the health of its consumers. However, cowpea faces several production constraints among which are diseases, insect pests, parasitic weeds such as Striga, and drought, which is becoming increasingly important in the cowpea producing zones of sub-Saharan Africa.

The new cowpea varieties presented today were jointly developed by the International Institute of Tropical Agriculture, Ibadan, in collaboration with the Institute for Agricultural Research of the Ahmadu Bello University, Zaria; the University of Maiduguri, Borno; and the Agricultural Development Programmes of Borno, Kaduna, Kano, and Katsina States - all based in Nigeria.