The use of crop modeling

methodology for the selection of early materials adapted to

those regions was considered in this assay. A growth analysis

of 99 early corn landraces was conducted at INIFAP.s Bajio

Experiment Station (CEBAJ) during the summer of 1997.

Using the CERES-MAIZE crop model, the genetic

coefficients were adjusted with such information. Eight

groups were identified in the 99 landraces according to the

"emergence to tasseling" and "tasselling to maturity" values

(P1 and P5). With these results, it is possible to simulate yield

potential of the landraces under different rainfed

environments using soil and historical weather information.

As an example, the genetic coefficients of the eight corn

landraces representing each group, were used to simulate

their yield potential at the northern Guanajuato region, where

corn is grown mainly under dry land conditions, (300 to 600

mm of annual precipitation). Simulation was conducted using

seasonal routine of CERES-MAIZE crop model included on

DSSATV 3.1. Eleven years of historical weather information

were used for this simulation. For this location, Landrace 36

presented the highest grain yield under both conditions. At

CEBAJ, Landrace 36 showed the lowest yield out of eight.

These results support the use of crop modeling in the

selection of genotypes for specific environments.