Nzola Meso Mahungu

The importance of being bitter—a qualitative study on cassava cultivar preference in Malawi

We conducted qualitative interviews in Nkhata‐Bay district in Malawi to elucidate why farmers preferentially grow cassava cultivars providing bitter roots. Cassava was mainly grown to produce flour for making the staple food, kondowole. Plants were identified as belonging to one of the 54 mentioned cultivars with local names. All the farmers stated that bitter taste of roots predicted toxicity and necessity for processing. Cultivars were grouped into “cool” or “bitter” based on whether the roots could be eaten fresh, or required processing before consumption as kondowole. Farmers strongly preferred cultivars grown for flour production to have bitter roots since this protected against theft, destruction by animals and deterred household members from unplanned harvest. Since processing is done by women bitterness empowers women to control the families staple crop. Bitter cultivars reportedly yielded more and roots produced an easier to mould kondowole. Bitterness and toxicity were not perceived as a problem.

Cassava commercialization in Southeastern Africa.

Purpose - Cassava production surged noticeably in Southeastern Africa beginning in the 1990s. The purpose of this paper is to examine the commercial responses and food security consequences of cassava production growth in the region. Design/methodology/approach - The paper incorporates a mix of quantitative analysis, based primarily on original analysis of national farm household survey data, together with key informant interviews with value chain participants in the three neighboring countries of Malawi, Mozambique and Zambia. Findings - In the cassava production zones, cassavas high productivity translates into per kilogram carbohydrate costs 60 per cent to 70 per cent of the cost of cereals such as maize and wheat, thereby opening up a range of profitable opportunities for commercialization of cassava-based foods, feeds and industrial products. Despite this potential, cassava commercialization in Southeastern Africa remains in its formative stages, with only 10 per cent to 30 per cent of production currently marketed. Unlike West Africa, where cassava commercialization has centered on marketing prepared cassava-based convenience foods, the emerging cassava markets in Southeastern Africa have centered on fresh cassava, low value-added cassava flour, and experiments in industrial processing of cassava-based starches, biofuels and feeds. Strategic investment in a set of key public goods (breeding, training in food sciences and food safety, and research on in-ground cassava storage) can help to shape this transition in ways that benefit both commercial interests and the food security of vulnerable households. Originality/value - The paper compares cassava commercialization across differing agro-climatic zones, policy environments and food staple zones.

The effect of genotype, location and season on cassava starch extraction

When cassava is harvested too early, it often leads to reduction in yield, while delayed harvest leads to development of woody and fibrous tuberous roots, and reduction in starch content. The optimum harvest time is not known. The objectives of this study were to determine the effect of genotype, location and season on starch extraction in order to find an optimum harvest regime for cassava, and to find the best parameter for monitoring starch levels in cassava tuberous roots. Results showed that genotypic effect was large for starch weight, starch extraction rate on fresh weight basis, and root dry matter content. This suggested that high starch weights could be realised by selection of suitable varieties for starch extraction. It was found that cassava harvesting and starch extractions should be done between October and November since the highest starch extraction rates were achieved during that period, and drying of the extracted starch using the open air method was fast and convenient. The results also suggested that starch levels can efficiently be monitored using starch extraction rate on fresh root weight basis. Starch content on fresh root basis and root dry matter content can also be used to determine the optimum time to harvest cassava for starch extraction but were inferior to starch extraction on fresh root weight basis.

Measuring the impact of plant breeding on sub-Saharan African staple crops:

Many countries in sub-Saharan Africa (SSA) are facing huge challenges regarding food insecurity, low agricultural output, and agriculturally incurred environmental degradation. A sustainable and increased crop productivity and diversity is essential to achieve food security in a socially, economically, and environmentally sustainable way. Plant breeding is an important factor contributing to the increased crop productivity and diversity, giving farmers access to genetically improved cultivars that yield more, have better resistance to biotic and abiotic stresses, and meet consumer expectations. To motivate and encourage further investments, it is important to measure the actual impact of breeding. This review considers available research on the impact of breeding through yield gain and of food security, focusing on 10 important staple crops in SSA. The overall impression is that breeding produces a very high return on investment. Such investments remain centerpieces for meeting the challenges in this region. The discussion focuses on the most important future breeding priorities for each crop, the actors involved, and the importance of mechanisms for dissemination and farmer adoption, and concludes with some policy recommendations.