Título
Farmer management of maize diversity in the Central Valleys of Oaxaca, Mexico: CIMMYT INIFAP -- 1998 Baseline Socioeconomic Survey
Autor
Mauricio Bellon
Nivel de Acceso
Acceso Abierto
Materias
Resumen o descripción
Descriptive data from the sample survey of households in the study communities enable us toprofile the characteristics of: (1) farm households; (2) the maize populations they grow, based ontheir own descriptors and the perceptions of both men (production decision-makers) and women(consumption decision-makers);1 and (3) farmers’ seed selection and management practices.Farm households♦Households average between 4 and 6 members, and the mean age for production decision-makers is about 50 years. All production and consumption decision-makers are Spanish-speaking. Indigenous languages are used more in Mazaltepec and Santa Ana.♦By some indicators of wealth (television, refrigerator, electricity, gas stoves), from a globalperspective, survey households are not poor.♦Huitzo depends more on local nonfarm income than other survey sites; Huitzo and Valdefloresdepend less on local agricultural production; Huitzo and Mazaltepec depend less on remittances.In San Lorenzo, Santa Ana, Valdeflores, and Amatengo, at least one-fourth of households reported that remittances are an important source of income. ♦ All sites except Huitzo reported average per capita maize requirements higher than the nationalmean. The average farm household in the survey communities is a net seller in some years and a net consumer in others. The market for maize appears to be local. ♦ The average farm size in 1996 was 3.5 ha with 3 ha of maize. The mean number of soil types per farm, as well as the extent of land fragmentation, was lower in Huitzo and Amatengo. Fragmentation seems to be highest in Santa Ana and Valdeflores. Tenure arrangements contrast sharply between communities Maize populations ♦ Maize populations grown by farm households have been classified based on farmer taxonomy into 5 classes of Blanco (white-grained) maize, 3 classes of Amarillo (yellow-grained) maize, 1 Negro (black or purple-grained) maize, 1 Belatove (pinkish-grained) maize, 1 Pinto (grain of mixed color), 1 Mejorado (improved) clas and a Tepecentle variety. Tepecentle is a distinct maize race, and all other classes are found within the Bolita racial complex. ♦ Blanco types occupy over 80% of the area and representing two-thirds of the seed lots planted in 1997. Improved maize was grown almost exclusively in Huitzo, which has the most irrigated land. Even in Huitzo, it occupied only 7% of the area in the survey year. ♦ Subjective yield distributions suggest that: (1) improved maize dominates local types; (2) Blanco types dominate colored-grain types; and (3) consumption partners (women) are significantly more pessimistic than production partners (men). The yield distributions of Santa Ana are significantly different from those of Huitzo, Mazaltepec, and Amatengo. ♦ Farmers in the survey communities grow maize primarily for food or feed rather than grain sales, and they are interested in many characteristics in addition to yield. While they rate improved maize well in terms of grain yield and fodder, they rank it as a poor supplier reative to local varieties. Among the local varieties, Blanco types were rated superior to colored-grain types with respect to grain yield per hectare, suitability for sale and most consumption characteristics. Amarillo was highly rated for tlayudas, feed, and fodder, and Negro and Belatove have shorter growing seasons • Although men and women rank the importance of characteristics differently, four of the top five characteristics are the same for both sexes: (1) drought tolerance; (2) resistance to insects in storage; (3) produces "something" even in bad years; and (4) grain weight Men added grain yield per hectare and women added the taste of tortillas to the set of most important characteristics. Seed management • Farmers know their varieties—they have grown them for an average of over 20 years. The concept of "own seed" is ambiguous, however, since a large proportion of farmers also combine and replace seed lots (see definition of terms in Methods section). The highest propensity to give, exchange, combine, or replace seed was found in Santa Ana, although these practices were also observed in San Lorenzo and Amatengo. Exchange is primarily local. • As has been found elsewhere in Mexico, the seed selection criteria used by farmers are those related to grain and ear health, grain size, grain filling, and ear size. Less than half of survey farmers reported that they separated food or feed grain from seed at harvest time. The most frequent form of selection is the continual separation of good ears from those removed every few days for preparation of nixtconal. Perceptions differ between men and women regarding responsibilities for seed management and selection, but women's role is likely to be substantial in this separation activity. • There is evidence that farmers are exerting strong indirect selection pressure for resistance to insect damage in storage, but no direct pressure on husk cover. Husk cover is important as a "fast line defense." Maize diversity • Farm-level diversity appears to be greatest in Santa na and San Lorenzo and least in Amatengo and Valdeflores, as measured by numbers of varieties per farm and by a Simpson index based on area shares. • Community-level diversity bears no direct relationship to farm-level diversity because of differences in the scale of measurement. Diversity remains high at the community level in San Lorenzo and is relatively low in Santa Ma. • There is no strong evidence that farmers in these communities recognize a loss of maize populations during the past two decades. Implications for further work Some implications for further work can be drawn from the descriptive data. The multivariate analyses that follow this baseline summary should provide additional insights. • Given that markets are local, most households both consume and sell maize, and that a small proportion of the maize they produce passes through the market, enhancing characteristics based on current market valuation is not likely to affect farmer welfare appreciably. A fonnal hedonic stile& is probably not warranted. • Like studies elsewhere in Mexico (Perales et at 1998), this study confirms that in maize production farmers are not motivated strictly by yield per hectare or profitability but by a number of concerns. In the Central Valleys of Oaxaca, these include consumption-related characteristics. This does not imply that grain yield per hectare does not matter, but that (I) "yield" has many components on-farm (grain weight post-harvest production; the lower tail of the yield distribution; drought tolerance), and (2) farmer welfare can be improved by enhancing other characteristics. The large yield gap between farmers' expected yields and potential yields further suggests that addressing agronomic or other constraints may be more effective in improving on-farm yields than breeding. Other characteristics may be easier to improve than grain yield per hectare under farmers' conditions through participatory breeding techniques, and they mew also contribute to farmer welfare. Appropriate interventions may include development gland training in techniques designed to improve storability or agronomic practices. • Fanners rate their own varieties fairly low with respect to several of the agronomic chara .cs they identify as most important, suggesting that their seed selection practices are not as effective as they would want than to be for these traits. They rate them high for consumption characteristics, suggesting that their selection practices for these traits are adequate to meet their needs. In other words, the tools qfprefessional breeders and farmer-breeders may be complementary. • While there are differences between men and women in the relative importance of certain maize characteristics, they agree on those that are most important There we no obvious gender implications associated with addressing any one the major characteristics identified by survey farmers through breeding or or other strategies. • There may be a means through simple management methods to increase farmers' selection pressures for resistance to ints in storage, including emphasis on husk covet. Theeffects ofdirect selection, for husk cover need to be tested more fully. • There are likely to be strong gender implications related to the strategies designed to enhance seed selection and management practices. Women who make decisions regarding seed management, selection, and storage must participate actively in any experiments or tests. • The propensity to exchange, combine, and replace seed lots for the same variety has implications for intra-varietal genetic diversity and for the genetic gains that can be achieved through improved methods of mass selection, which depend on retaining seed from the harvest over successive seasons. Additional, focused research is required to understand farmers' seed management practices and their (Pets on genetic diversity. • Farmers are most likely to continue growing the Blanco types because these maize varieties supply more of the characteristics they demand than other local classes of maize. This implies that encouraging farmers to maintain the Blanco types would cost less in terms of additional economic incentives. There appears to be more than a difference in grain color between Blanco and the other local classes of maize, however. Grain color may "mark" other traits that are significant for maintaining diversity in the region. More genetic work is necessary to identify populations within and among the classes identified by farmers that are key from a genetic diversity standpoint as well as a crop improvement perspective.
Fecha de publicación
1999
Tipo de publicación
Libro
Recurso de información
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application/pdf
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Inglés
Audiencia
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Repositorio Orígen
Repositorio Institucional de Publicaciones Multimedia del CIMMYT
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