Release of More Higher pro-Vitamin A Cassava to fight Micronutrient Deficiency

Hernan Ceballos (left) CIAT Plant breeder with IITA Cassava breeders Peter Kulakow (middle) and Elizabeth Parkes (right), harvesting the new cassava varieties in Ibadan

Three newly improved vitamin A cassava varieties with yellow roots have been released by the Nigerian government, stepping up efforts to tackle the problem of vitamin A deficiency especially among women and children in the country. These new varieties were developed jointly by IITA and the National Root Crops Research Institute (NRCRI) Umudike.

The three varieties—UMUCASS 44, UMUCASS 45, and UMUCASS 46—are the second in the series of pro-vitamin A varieties released in the country, and are commonly known as NR07/0220, IITA-TMS-IBA070593, and IITA-TMS-IBA070539.

The new varieties have a pro-vitamin A content that averages 10 parts per million (ppm) based on fresh roots as compared to the first series (UMUCASS 36, UMUCASS 37, and UMUCASS 38 commonly known as IITA-TMS-IBA011368, IITA-TMS-IBA1371 and IITA-TMS-IBA011412) that were released three years ago with a pro-vitamin A content of between 6-8 ppm.

Dr Peter Kulakow, IITA Cassava Breeder, said that the development of the varieties demonstrates strong collaboration between scientists at NRCRI and IITA which benefits Nigerian farmers and especially women and children who suffer from vitamin A deficiency.

Afflicting almost 20% of pregnant women and about 30% of children under the age of five, vitamin A deficiency results in stunting in children, predisposes them to sicknesses such as diarrhea and measles, and even premature death. In pregnant women, vitamin A deficiency results in night blindness and increases the risk of mortality.

Measures to address this deficiency include dietary diversity, fortification, supplementation, and now biofortification.

In 2011, researchers from IITA and NRCRI with funds from HarvestPlus developed the first series of biofortified pro-vitamin A cassava varieties to help reduce the incidence of vitamin A deficiency especially in the rural communities.

Dr Chiedozie Egesi, NRCRI Cassava Breeder, said this newer set of pro-vitamin A cassava varieties will play a role in attaining the goals of the Cassava Transformation Agenda of the Federal Government of Nigeria and help improve cassava food products such as gari, fufu, high quality cassava flour, cassava bread, and starch.

“This new set of pro-vitamin A cassava varieties have increased beta-carotene levels as well as matching agronomic characteristics as an incentive for better farmer adoption,” he added.

Prior to their release, participatory varietal trials involving farmers were conducted across 10 states in Nigeria, the world’s top cassava producer, cutting across the different agroecological zones.

The varieties have potential yields of 32–36 tons per hectare; they branch either moderately or profusely and possess yellow roots.

Farmers love the varieties, helping to increase the acceptance of “yellow cassava”, thanks to HarvestPlus; researchers forecast a high adoption rate for the varieties.

The next steps include the rapid production of breeders’ and foundation seed stock so that commercial farmers will have access to these new varieties. This process involves advocacy and education on the processing, marketing, and storage of products from these varieties to derive the maximum benefits from these varieties.

Plant Breeders are not resting, Hernan Ceballos, cassava breeder from CIAT in Colombia has developed biofortified germplasm that IITA breeders are actively using in crosses to select for even higher beta carotene germplasm.

The development of these varieties is funded by HarvestPlus. Other partners include the International Center for Tropical Agriculture (CIAT), the Brazilian Agricultural Research Corporation (Embrapa), and various Nigerian government agencies.

MAIZE: Nigeria releases first generation of herbicide-resistant hybrids

The Nigerian National Variety Release Committee (NVRC) has released the first generation of maize hybrids, resistant to metsulfuron methyl herbicide, that are also endowed with resistance to the noxious parasitic weed Striga hermonthica.

The hybrids were developed by the International Institute of Tropical Agriculture (IITA) in partnership with DuPont Pioneer Seeds using conventional breeding with funding from IITA and the Integrated Striga Management in Africa (ISMA) project as part of strategies to control S. hermonthica in maize.

The hybrids were released as P48W01 and P48W02 and are recognized as IITA IR-Maize Hybrid 2 and IR-Maize Hybrid 4. The hybrids have a yield potential of up to 5 t/ha under Striga infestation in comparison with local varieties that produce less than 1 t/ha in such conditions.

“These hybrids are the product of introducing a single nuclear gene that confers resistance to imidazolinone herbicides, including metsulfuron methyl (MSM), into inbred lines with known field resistance to S. hermonthica,” Dr Abebe Menkir, IITA Maize Breeder, said.

Recent baseline studies conducted under the ISMA project showed that farmers ranked Striga as the number one constraint to maize production in northern Nigeria, with 50 to 100% of the households reporting Striga incidence in their farms. The parasitic weed infests more than 9 million ha planted to millet, maize, and sorghum in Nigeria and severely lowers the production capacity of these crops.

Dr Menkir said yield losses in maize from damage by S. hermonthica varied from 20 to 80% among subsistence farmers, but 100% loss could occur in susceptible cultivars under severe infestation in marginal production conditions.

The released herbicide-resistant hybrids allow seeds to be planted that have been treated with low doses of metsulfuron methyl herbicide. This targets S. hermonthica before or at the time of its attachment to the maize root, killing the parasite underground before it inflicts damage on the crop. These hybrids can thus be used to deplete the Striga seed bank in the soil and minimize yield losses in subsequent cereal crops. MSM-reated seeds of these hybrids can be integrated into the diverse farming systems in Nigeria because the herbicide effectively controls the parasite at a low rate of application.

The ISMA project works with the private sector to catalyze the process of producing and marketing treated seeds of herbicide-resistant maize hybrids to smallholder farmers in Nigeria to control S. hermonthica.

Other collaborating partners engaged in extensive testing of these hybrids include the Institute for Agricultural Research (IAR) and Agricultural Development Programs in Bauchi and Kano States.