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IFRPI reort

Adoption of hybrid maize in Zambia: effects on gender roles, food consumption, and nutrition

Shubh K. Kumar


This report examines the role of hybrid maize adoption in Eastern Province, Zambia, in improving the welfare of the population. Improving agricultural productivity of farmers in Zambia is important for the success of the country's new economic growth strategy. Past investment in hybrid maize research has developed a potential for increased productivity that needs to be fully utilized.

Maize is the most important food in the Zambian diet. Its primacy has grown steadily as the result of past government policies that encouraged its production in all parts of the country, including areas where it may not be economically efficient to grow maize. Given current market liberalization efforts, it is likely that maize production in general and marketed maize production in particular will remain viable only in areas near the major population centres because of transport costs. Such a contraction in maize area would increase the need for improved technologies to raise agricultural productivity in outlying areas to maintain their current level of income. Since most of the previous agricultural research in Zambia has been on maize, this crop offers more options for increased productivity than other crops. However, even if other crops are promoted, the experience in optimizing growth and welfare outcomes with hybrid maize should be useful.

Until the late 1980s, aggregate increases in maize production were limited, despite a substantial expansion of hybrid maize adoption and fertilizer use. Since then, a wide range of improved maize varieties suitable for small farms has been released by agricultural research stations in Zambia. The potential thus exists for rapid improvements in productivity, income, and welfare.

This report examines farm household-level factors that influence the adoption of hybrid maize in Eastern Province and the implications of adoption for improvement in household income, food consumption, and nutrition and health of the rural population. The characteristics of adoption, such as who adopts and what other changes are associated with it, in particular its implications for household labour allocation and intra-household access to resources, are expected to influence food consumption and the nutrition status of the population.

The analytical approach is geared to trace the distributional and welfare consequences of hybrid maize production. An instrumental variable approach is used to make predictions on the effects of hybrid maize adoption. Previous IFPRI work has generally shown that incomes rise with the adoption of improved agricultural technologies, but child nutrition does not necessarily improve. In this report, the implications of a wide range of resource allocation decisions that are associated with adoption and that influence the distribution of welfare improvements are examined. These include changes in women's access to resources and decision-making, labour allocation decisions, and characteristics of cash flow and allocation of income. Area-level characteristics, such as access to infrastructure and markets and geographical variation in adoption rates, are also considered. Although the analysis identifies adoption of hybrid maize production as a key element of technological change in agriculture, adoption is nearly always ace companied by increased use of chemical fertilizers and an expansion of cultivated area associated with a shift from hoe to ex-plough use.

This report is based on a collaborative study in Eastern Province conducted in 1986 by the IFPRI, with the University of Zambia's Rural Development Studies Bureau and the Zambian National Food and Nutrition Commission, to examine the growth and equity effects of technological change in agriculture. The results of this study were presented to the government of Zambia between 1987 and 1990, and this report presents a detailed analysis of those results.

Eastern Province is a major agricultural region of Zambia; it consistently produces large maize sure pluses. Its predominantly rural population depends on agriculture for nearly 80% of its income. Agriculture is mainly smallholder, with an average farm size of 2 to 3 ha. Eastern Province has some of the best agricultural land in the country, but, as in many other parts of Africa, it has a single rainy season, thus providing only one main growing season for farmers.

Study sites, located in each district, were selected to provide a representative sample of households from the province and its two main ecological zones- plateau and valley. During 1986, 330 households, drawn from a stratified random sampling, were visited monthly and interviewed on agricultural production practices, labour allocation, off-farm income sources, food and non-food consumption, morbidity, and intra-household decision-making. In addition, the weight and height of each household member were recorded four times during the year to determine anthropometric status and hence nutrition status.

Among the 10% of farmers with the largest farms in Eastern Province, nearly all with more than 5 ha adopted hybrid maize. However, adoption was also substantial among the smaller farms, with about 50% of those in the 3 to 5-ha category, 37% in the 2- to 3-ha category, and 25% in the 1- to 2-ha category adopting hybrid maize. Data indicate, however, that hybrid maize production is more profitable for smaller farms. Marginal improvements in income deteriorate in farms of more than 4 ha under hybrid maize. This implies that policies directed to adoption by larger farmers may be contributing to lower productivity gains from this technology.

Because it is harder to process and store hybrid maize, farmers grow local maize for home consumption and sell most of the hybrid maize. Where labour supplies are short, farmers are likely to devote more attention and resources to local maize. Policy measures to improve local storage and processing options could further improve hybrid maize productivity because these measures would shift its place in the cropping system from cash crop to food crop, so that farmers would give it priority in timing of planning and other operations. The market liberalization now under way should provide an incentive for investments in low-cost rural storage improvements, for which technologies already exist. Improvement in rural infrastructure will also be critical.

Female-headed households have a lower adoption rate for hybrid maize (22%) than male-headed households (34%). However, the pattern varies across farm sizes. Female-headed households with less than 3 ha have a lower adoption rate than those with more than 3 ha. This indicates that once women overcome resource constraints, they are just as likely, or even more likely, to become technological innovators.

Women play an important role in agriculture in both female- and male-headed households. About half the cultivated area is either independently or jointly managed by women. This share is highest for local maize and traditional cereals (60% and 70%, respectively). Women have less involvement in hybrid maize than in any other crop, with only 25% of the area independently or jointly managed by women. Moreover, adoption of hybrid maize by a household reduces women's share in crop management and agricultural decision-making, independently of farm size. This may be because women have less access to resources such as credit, inputs, and human resource improvements, which are essential for producing the new crop varieties, or it may reflect men's desire to control income from cash crops.

Women provide nearly 60% of family labour in agriculture. With adoption of hybrid maize, however, men tend to shift from non-agricultural activities to agriculture, increasing their share of labour. Although the adoption of hybrid maize reduces the amount of time that women spend in farm work, the time they spend on household maintenance activities increases.

The distribution of crop income within households reflects the extent of household members' participation in crop management. Therefore, women's income and the value of their time, compared with men's, declines with adoption of hybrid maize. The failure to use women farmers effectively, in both female- and male-headed households, contributes to productivity losses by shifting women's labour away from farming activities.

Policies that support participation of women in decision-making and production of improved grain varieties could improve efficiency and household food consumption and children's nutrition status. Women's income and time spent in household maintenance activities are significantly positive factors in improving household dietary intake, but only women's income share is significant for improving child nutrition. This suggests that patterns of child care available are compatible with women's work in rural Zambia. The trade-off observed between women's work at home and household food consumption is very small in absolute terms and could be reduced with better access to improved technologies for household maintenance activities, such as hammer mills for grinding grain. With a larger share of income, women are better able to obtain access to such household maintenance improvements. For exe ample, women themselves now pay for most of the household food processing costs. Viewing women's maintenance and home production roles as simple trade-offs in family welfare, and especially child welfare, is therefore unjustified, given all the dynamics involved.

In examining household food intake, this study uses a modified food expenditure record to compute calories and protein consumed. Micronutrients anaIyzed include iron, calcium, and vitamins B1, B2, and B3, all of which are important in energy metabolism. Diet diversity is also measured. The results indicate that areas that had a high level of adoption of hybrid maize had a higher level of food intake than areas of low adoption. At the household level, however, intakes improved with adoption of hybrid maize only for the smaller farmers. The larger farmers who adopted hybrid maize had a lower consumption of nutrients. This finding is consistent with the limited profitability found when more than 4 ha of hybrid maize was planted. This adoption pattern helps reduce income inequality between small and large households, while increasing income inequality within large farm households. Decisions on household food consumption and income are closely interrelated. This is plausible in a farming system facing pronounced seasonal labour shortages, where farmers cannot provide the necessary labour if the food available is insufficient to maintain their energy. If they sell their food crops to increase income, their food supply will fall. Similarly, if they devote more labour to the cash crop, the food crop will suffer. Measures to improve food consumption are therefore likely to be as effective as measures to improve income in making sustainable changes in welfare.

Analysis of the nutrition status of children shows that both household income and women's income are significantly positive for the longer-term nutrition indicators, such as height-for-age. The time women spend on household maintenance activities is not significant and contributes more to short-term nutrition improvement. Whether a male or a female headed a household was not a significant factor in improving child nutrition. The important factor is who manages the crop and therefore allocates the income from it. Better access to health services and improved sanitation facilities are significantly associated with improved child nutrition. Some catch-up growth in height between the ages of 5 and 10 years is indicated, and there is no difference in the nutrition status of boys and girls.

Efforts to promote productivity gains through better access to inputs by the smaller farmers, and to ensure access to physical and human resources by women, including those in male-headed households, will be important if the full potential of new technologies for improving food production and welfare of the population is to be realized. The progress of new hybrids and composite varieties of maize in the farming system also needs to be monitored to ensure that they are being grown not only as cash crops but also as food crops and, therefore, are receiving the same degree of priority as local maize. This will be facilitated by the effects of market liberalization on incentives for better on-farm storage for maize. Spread of small-scale food-processing facilities would also have a favourable impact on the integration of improved maize varieties into the farming system. Other areas that need policy attention are the reduction in diet diversity and micronutrient intakes observed in areas with higher levels of adoption, and the increase in welfare inequalities between high- and low-adopting areas.

News and notes

Infoods information by E-mail

The International Network of Food Data Systems (INFOODS) was organized in January 1983 to provide leadership for the development of standards and guidelines for the collection, compilation, and reporting of food component data, with the aim of establishing and coordinating a worldwide network of regional data centers directed toward the generation, compilation, and dissemination of accurate and complete data on food composition. It is establishing a global system of regional food composition databases with the capacity to exchange data electronically.

INFOODS has two mailing lists, one for general food composition discussions and a second, more specialized list for updates to the food component tagging system. Subscriptions to the food composition discussion list can be obtained by anyone involved in this area of nutrition by sending mail to food-comp-request at INFOODS.UNU.EDU.

To keep up with data being generated for food component tagnames, the tagname list is available from the INFOODS server in New Zealand. It can be accessed from a WWW server located at WWW.CROP.CRI.NZ. If you have a Mosaic browser, it can be accessed by HomePage=http://

A small group participates in updating the food component tagging system list by invitation of special request to the secretariat:

A subscription to a nutritional epidemiology list at the Bundesgesundheitamt in Berlin may be obtained by sending electronic mail to listserv@db0tui11 on bitnet with one line in the message "subscribe NUTEPI your name" where your name is replaced by your full name.

IUFoST Sponsorship of Short Courses and Workshops

IUFoST is pleased to announce continuance of its programme to support short courses and workshops in the area of food science and technology. Proposals addressing critical needs in developing countries will be given highest priority. Any organization or individual with appropriate capabilities may submit a proposal, although preference will be given to representatives from countries that are members of IUFoST.

IUFoST's contribution will consist of 1) co-sponsorship; 2) advice, when requested; and 3) limited financial support. The latter is intended primarily to provide payment of APEX airfares of one or two foreign speakers.

To initiate the application process, a short letter containing the proposed date, programme topic and justification, intended audience, suitability of the facilities, and competency of the proposer(s) should be sent to:

Professor Owen Fennema

Chairman, lUFoST Scientific Activities Committee Department of Food Science

University of Wisconsin

Madison, Wl 53706, USA

If the initial proposal is deemed appropriate, a full proposal will be requested.

Books received

Fetal and infant origins of adult disease. Edited by D. J. P. Barker. British Medical Journal, London, 1993. (ISBN 07279-0743-3) 343 pages, hardback.

This may be the most important book for nutritionists that the Food and Nutrition Bulletin has ever reviewed. In the past, low birth weight due to foetal undernutrition was also common in today's industrialized countries. The book is a collection of 31 previously published papers by Barker and colleagues finding that low weight at birth and at one year of age is associated with higher morbidity and premature morbidity from chronic degenerative disease in later life, at least in individuals exposed to today's high-fat, high-calorie diets. Men in Hertfordshire, England, who suffered foetal growth retardation at birth between 1911 and 1930 were found to have higher mortality from hypertension, stroke, and cardiovascular disease in association with higher levels of cholesterol, apolipoprotein B. clotting factors, fibrinogen, and factor Vll, all risk factors for ischemic heart disease. The same relationships were seen with stunting at 12 months of age. About 70% of the men on whom early weight data were obtained were either identified or the cause of their death determined. High 24-hour plasma glucose, increased insulin tolerance, and adult-onset diabetes are also more common among men in Hertfordshire 46 to 54 years of age with low weight at birth and at one year of age who were born between 1920 and 1930. Birth weight was also related to adult lung function and death from chronic obstructive lung disease in these men. Both prenatal and postnatal factors influence early growth and thereby differences in average height. It was more difficult to trace the women because of marital name changes, but enough were located to establish the same relationships.

In a study of 449 infants born between 1935 and 1943 in a maternity hospital in Preston, England, adult blood pressure of men and women was strongly predicted by a combination of high placental weight and low birth weight. Since publication of the book, many additional articles with similar findings have been published by this group. As a group, these studies have devastating implications for the adult lives of the huge number of low birth weight and stunted children in the world today who are likely as adults to be consuming diets relatively high in fat and cholesterol. Every nutritionist needs to become familiar with this evidence, and that from earlier studies, linking low height and weight in early childhood in lower socio-economic groups to lower cognitive performance (see Food and Nutrition Bulletin, Volume 14, Number 3, September 1992).

A new paradigm for understanding the relationship between early malnutrition and health and disease throughout the entire life-span is emerging. This book is important for everyone with a need to understand the mounting evidence for this new paradigm.

Child growth and nutrition in developing countries. Priorities for action. Edited by Per Pinstrup-Anderson, David Pelletier, and Harold Alderman. Cornell University Press, Ithaca, N.Y., USA, and London, 1995. (ISBN 08014-8189-9) 447 pages.

The outstanding editors and authors of this volume have provided a comprehensive and critical review of current knowledge of programmes for nutritional improvement with special attention to the multiple constraints on their implementation. This book attempts to communicate past experience as a means of enhancing the probability of more success in future initiatives. The book does not attempt to deal in depth with the magnitude of malnutrition and its consequences, topics that are well covered in other recent publications. Instead, it focuses on the issues of household behaviour and interventions that influence it, including nutrition education and growth monitoring, as well as interventions directly influencing health and access to food, community participation, multisectoral planning, nutrition, and health information.

The amount of food available in the home is not a reliable indicator of that consumed by the young child and of interactions of the child with caretakers and with their environment. The overview by the editors emphasizes that child survival is not enough and that policy makers should be concerned with the quality of the survivors. Cost estimates for child survival programmes reveal the gross inadequacy of the expenditures by most developing countries. Nutrition policy makers and planners should turn to this book for effective and sustained initiatives for the alleviation of malnutrition.

S.O.S. for billion. The conquest of iodine deficiency disorders. B.S. Hetzel and C.S. Pandav. Oxford University Press, Bombay, 1994. (ISBN 0-19-563552-3) 285 pages, paperback.

At the beginning of the decade, it was estimated that a billion people were at risk for iodine deficiency disorders (IDD). As the result of a concerted advocacy effort by the International Council for the Control of iodine Deficiency Disorders (ICCIDD) and the strong support of UNICEF and WHO, rapid progress is being made in the iodation of salt for the prevention of IDD. This book is edited by the Executive Director and Regional Directors of ICCIDD for South-East Asia, and its chapters are written by those engaged in the ICCIDD initiative. They describe the global progress in preventing IDD, the specific programmes that are proving effective, and the successful experiences of individual countries. It is written in non-technical language and should be particularly useful for policy makers.

Physiological and clinical aspects of short-chain fatty acids. Edited by John H. Cummings, John L. Rome beau, and Takashi Sakata. Cambridge University Press, Cambridge, 1995. (ISBN 0-521-44048) 575 pages, hardback.

This volume examines the role of short-chain fatty acids in digestion, in the function of the large intestine, and in human health. Short-chain fatty acids are the major product of bacterial fermentation of dietary carbohydrates in the human and animal large intestine. They provide a means whereby energy from carbohydrates that have not been digested in the upper gut can be salvaged from the caecum and colon. It is now increasingly recognized that they may have a significant role in protecting against large-bowel disease and in tissue metabolism. The 33 chapters are written by authors from eight industrialized countries and review every aspect of the topic. The volume is the first comprehensive reference source on this topic.

Glutamine: Physiology, biochemistry and nutrition in critical illness. Wiley W. Souba. R. G. Landis, Austin, Tex., USA, 1992. (ISBN 1-879702-36-3) 105 pages, hardback. US$89.95, $108.00 worldwide.

This slender volume is important because of the high rate of glutamine utilization that occurs in stimulated lymphocytes and macrophages, making it essential for the normal functioning of these cells in the immune response. The catabolic alterations in interorgan glutamine flow that occur following infection are profound but are rapidly reversed with recovery. Thus the value of glutamine-enriched diets is controversial. This book should be in nutrition libraries, but its cost places it beyond the reach of most individuals.

Cultivating crisis: The human cost of pesticides in Latin America. Douglas L. Murray. University of Texas Press, Austin, Tex., USA, 1994. (ISBN 0-29275169-0) 177 pages, paperback.

Since World War 11, the Green Revolution has boosted agricultural production throughout the developing world. However, the massive pesticide dependence associated with it has caused environmental damage and, under some circumstances, serious public health problems. The volume is based on 10 years of field research and considers both the macroeconomic and the geopolitical aspects of pesticide dependence, as well as the micro-consequences for communities and individuals. Although the book is based on experiences in Latin America, its observations are applicable to nearly all developing countries. It will be of great interest to anyone concerned about pesticide overuse and misuse.

Environment and agriculture: Rethinking development issues for the 21st century. Winrock International, Morrilton, Ark., USA, 1994. (ISBN 093359585-9) 265 pages, paperback.

This book is the proceedings of a 1993 symposium. It focuses on five topics: conserving and enhancing soil resources for the future; water resources, agriculture, and the environment; poor people, resources, and the environment; forest resources and forestry policies; range and wildlife resources; and genetic conservation and biodiversity. In common with the preceding book, it notes that poverty alone cannot be blamed for the environmental damage being done by agriculture in poor countries, since overirrigating and overuse of pesticides by well-to-do large or commercial farms are doing the most damage. It chronicles the transition in progress in one century from a resource based agriculture, in which almost the only way to get growth was to expand the area cultivated, to a science-based agriculture, in which natural resources play a still important but diminishing role. A closing chapter considers how this transition must be brought to the farmers of all countries.

Educational handbook for nutrition trainers: How to increase your skills and make it easier for students to learn. A. Oshaug, D. Benbouzid, and J.-J. Guilbert. World Health Organization, Geneva, 1993. Paperback. SwFr 65; US$58.50 (developing countries SwFr 45.50).

This handbook has been adapted from one developed and improved over two decades and used in hundreds of training workshops for physicians and nurses. It is now designed for the training of nutrition and nutrition-related personnel. It is a tool for teachers and not a self-learning manual. The first 67 pages focus on how to identify priority problems and define educational objectives. The next 22 pages deal with planning and evaluation systems. Seventy-seven pages are devoted to the teaching-learning concept and designing a student-centered learning program. Fifty-six pages discuss the design of evaluation instruments and assessing student performance using oral and written examinations. A final chapter describes how to organize an educational workshop. Its concise bibliography provides additional references on health needs and resources and organization of health services; medical education and education in general, educational objectives, programme planning, teaching methods, and techniques; and evaluation, tests, and measurements. This volume is focused entirely on methodology, although it does provide guidance as to how to choose the substance to be communicated. Inexperienced trainers will find this volume valuable, and it is suggested that it be used on a team rather than on an individual basis. Even experienced trainers will find that this volume provides a useful check-list and valuable suggestions that can significantly improve the quality of their nutrition teaching.

Evaluation of certain veterinary drug residues in food. Forty-second Report of the Joint FAD/WHO Expert Committee on Food Additives. WHO Technical Report Series no. 851. World Health Organization, Geneva, 1995. (ISBN 92-4-120851-1) 42 pages, paperback. SwFr 10; US$9 (developing countries SwFr 7).

Monitoring universal salt iodization programmes. Edited by Kevin M. Sullivan, Robin Houston, Jonathan Gorstein, and Jenny Cervinskas. PA MM/M I/ ICCIDD, Atlanta, Gal, USA, and Ottawa, Canada, 1995. (ISBN 0660-16000-5) 101 pages, paperback. Requests for copies can be directed to: PAMM/Department of International Health Rollins School of Public Health of Emory

1518 Clifton Road, NE, 7th Floor
Atlanta, GA 30322, USA
Tel: 404-727-5724 Fax: 404-727-4590
The Micronutrient Initiative P. O. Box 8500 250 Albert Street Ottawa, Canada K1G 3H9 Tel: 613-236-6163 Fax: 613567-4349

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