Searching for Adaptation to Abiotic Stress: Ecogeographical Analysis of Highland Ecuadorian Maize

Crop Science

Torres, Elena¹  Parra-Quijano, Mauricio²  Tapia, César³ 

[1] Dpto. Biología Vegetal, Universidad Politécnica de Madrid, 28040 Madrid, Spain$$;International Treaty on Plant Genetic Resources for Food and Agriculture-FAO, 00153, Rome, Italy$$;Dpto. Nacional de Recursos Fitogenéticos, Instituto Nacional Autónomo de Investigaciones Agropecuarias, EC170353 Quito, Ecuador$$

关键词: Burgess Shale;    Naraoia;    trilobites;    gills;    exopod;    functional morphology;   

DOI  :  10.2135/cropsci2013.12.0813

学科分类：农业科学（综合）

来源: Crop Science

【 摘 要 】

There are 26 maize (Zea mays L.) races found in the Andean highlands of Ecuador. Knowing the environmental characteristics of the sites where these races occur is useful to understanding their adaptive capacities and to identify germplasm potentially adapted to abiotic stress conditions. Passport data of 1186 accessions from the Ecuadorian national collection were used. On the basis of the geographical coordinates of collecting sites, data were extracted for five climatic, two geophysical, and five edaphic variables. Additionally, a specific ecogeographical land characterization map for maize landraces was developed for the Ecuadorian Andes and, subsequently, an ecogeographical category was assigned to each collecting site. Wide ecogeographical variability was detected within and among races. Maize accessions were collected at sites with a seasonal mean temperature between 8.7 and 22.9°C, temperature annual range between 10.3 and 16.9°C, and December minimum temperature between 3.4 and 16.9°C. Seasonal precipitation ranged between 363 and 1809 mm and October precipitation between 18 and 171 mm. Ten accessions were found to be potentially adapted to extremely cold environments and 40 accessions to dry conditions. Most of the accessions were obtained from farms located at altitudes between 1900 and 2800 m with flat to moderate slopes. Only 37% of accessions were collected from sites with favorable soil properties regarding texture, depth to rock, pH, organic matter content, and fertility. Maize landraces were found in 28 of the 56 ecogeographical categories identified in the region, three of which were considered to be preferred environments and 10 to be marginal environments.

【 授权许可】

Unknown