Crop: Zea mays L. spp. mays (Maize)

‘Olotillo’ is considered the most important maize race in the Central Depression of Chiapas and it is probably the one showing most variation within the area. However, the presence of ‘Olotillo’ is also common in other regions of Mexico such as Oaxaca and Guerrero.

Traditionally, two variants of this landrace are cultivated, according to the colour of the kernel that can be either white (Olotillo blanco) or yellow (Olotillo amarillo). Farmers generally consider Olotillo a good landrace especially suited for poor and/or unfertilized solis, in fact, it can be relatively productive under limiting edaphic conditions (Bellon and Brush 1994).

Cultivation System: low-input conditions.

Geographical Information

Country: Mexico

‘Olotillo blanco’ is widely cultivated in the district (i.e. ejido) Vicente Guerrero, located in the central part of Chiapas; it is the largest and most populate district of the municipality of Ocozocoautala. Vicente Guerrero covers an area of approximately 5125 ha and is located 25 km from the city of Tuxala Gutierréz, the state capital, and about 18 km from Ocozocoautala. The lands in which the landrace is cultivated are part of the Grijalva river watershed between 800 and 900 m a.s.l. The climate of the area is classified as warm sub-humid with summer rain; the average annual temperature is around 24 °C while the annual rainfall circa 850 mm. Throughout the year there is a drought period from July to August. Overall, the climate is favourable for maize production (Bellon and Brush 1994).

Farmer(s) description:

Within the traditional cultivation area, it is not possible to establish how many farms are currently cultivating the landrace. However, the lands are divided into 31 different work sites (i.e. trabajaderos) each named after a specific location and characterised by well-defined boundaries with an average size of about 21 ha. The majority of farmers use both landraces and modern maize varieties according to the market demand. In the traditional cultivation area, farmers have an average of four scattered fields and some own as many as eleven fields: the average field size is 2 ha (ranging from 1 to 3.1 ha) (Bellon and Brush 1994).

Propagation system: Seed, self-pollination

Multiplication procedures and consequences on landrace diversity:

At harvest farmers select seeds as follows: i) harvested ears (of different varieties and/or landraces) are brought home and divided according to the variety; ii) farmer select and separate the largest ears well covered by the husk; iii) the selected ears are opened and examined, selecting those that fit the ideal ‘Olotillo blanco’ type according to kernel colour (i.e. white), size, density, shape, cob length and number of seed rows; iv) selected ears are shelled and larger undamaged seeds are kept for the following sowing (Bellon and Brush 1994).

Within the cultivation area many modern varieties and landraces are cultivated; considering that maize is an open-pollinated species and wind acts as main pollination agent, the coexistence of such materials in the same area make the preservation of a landrace such as ‘Oltillo blanco’ challenging. The intense farming activity in the area does not allow each farmer to isolate fields in order to maintain varietal purity. However, effective isolation is perhaps possible because of land fragmentation where a single farm consists of a number of discrete parcels scattered over a large surface. In addition, awareness of different flowering time can decrease the occurrence of cross-pollination between different materials. Few farmers use temporal isolation to keep varietal purity; however, most of the farmers in Vicente Guerrero do not consider such temporal isolation and consequently hybridisation can reasonably occur.

Management plan existence:

The landrace management relies completely on farming activities in the area. Currently, no technical or scientific support is given by other local authorities.

Added Values

Market - existing and novel:

Flour of ‘Olotillo Blanco’ is used to prepare some typical culinary preparations such as white Mexican tortillas. Its use is common in many areas of Mexico and ‒ thanks to the growing interest on traditional Mexican cuisine worldwide ‒ is also becoming important in other rich markets such as USA. However, due to lack of information, it is not possible to estimate the market value, especially of the material cultivated in the district of Vicente Guerrero (Ocozocoautala, Mexico).

Others (e.g. commercial/geographical brands or special traits):


In the 90s ‘Centro de Ecologia’ of ‘Universidad Autonoma de Mexico’, together with the Department of Applied Behavioural Science of the University of Calfornia Davis (USA) conducted a research study on how farmers managed maize landraces, including ‘Olotillo Blanco’ in the district of Vicente Guerrero (Ocozocoautala, Mexico) (Bellon and Brush 1994).

Farmers maintain ‘Olotillo Blanco’ primarily through seed selection. Spatial and temporal separation do not seem to be enough to maintain such landraces. In fact, the coexistence of improved maize variety in the same area might lead from uniform subpopulations of the landrace to heterogeneous populations through hybridisation.


Case study provided by Dipartimento di Scienze Agrarie, Alimentari e Ambientali (DSA3), Università degli Studi di Perugia (UNIPG), Italy.

Most of information were retrieved through bibliographic research (Bellon and Brush 1994).

  • Bellon MR, Brush SB (1994) Keepers of maize in Chiapas, Mexico. Econ Bot 48:196–209.