del trabajo. En el grano de almacén se observó que el maíz amarillo exhibió 50.3% de
incidencia de Aspergillus, 5.5% de Fusarium y 15.9% de Penicillium (71.7% en total).
En maíz blanco, la incidencia de Aspergillus fue de 44.6%, 6% de Fusarium y 10.4%
de Penicillium (61% en total). En campo, los maíces amarillos mostraron mayores inci-
dencias de Aspergillus (3.1%), Fusarium (76.9%) y Penicillium (11.6%) que los maíces
blancos (2.4, 63.6 y 7.9%, respectivamente). Los maíces amarillos DK-697 y DK-1060;
Garst 8222, 8285 y 8288; y Golden Acres 8112, 8311 y 8460 mostraron mayores inci-
dencias combinadas de hongos micotoxigénicos; mientras que los maíces blancos Tigre,
H-437, H-436 y Asgrow 7573 presentaron las menores incidencias. Los híbridos de gra-
no blanco UAP-1851, DK-2010 y Asgrow 7573 no presentaron incidencia de Aspergilli.
Los resultados indican que entre los hongos potencialmente micotoxigénicos detecta-
dos en maíz blanco o amarillo almacenado en el norte de Tamaulipas, Aspergillus (A.
flavus y A. niger) muestra las mayores incidencias (mayores al 40%), mientras que en
campo, las mayores incidencias las muestra Fusarium (mayores a 60%).
This research work consisted on two phases: in the first maize grain was collected
from June to September 2005 ((500 to 1500 g) in silos located in Díaz Ordaz (four),
Reynosa (three) and Río Bravo (three) counties in Tamaulipas. In total, 97 maize
grain samples were collected (54 of yellow grain and 43 with white grain). Ten grains
per sample were disinfested and cultivated in potato-dextrose-agar medium t o 30 ºC
during three days at darkness. The experiment was repeated twice. The number of
colonies or seeds infected by fungi from the genera Fusarium, Aspergillus and Peni-
cillium was registered. The identity of each genus was confirmed by the conidia and
mycelium morphology characterizations and the use of specialized literature. The sec-
ond phase was conducted under field conditions and laboratory. Twenty-five maize
hybrids (14 with yellow grain and 11 with white grain) from different companies of
México and USA were sown (august 30, 2005) in a randomized complete block design
with tour replications in Río Bravo, Tamaulipas. Harvest was conducted at January
23, 2006 and a composite of 200 g from each experimental unit was performed. Seeds
were analyzed in laboratory as been described in the first phase. In samples from silos,
yellow maize showed 50.3% of Aspergillus incidenc e, 5.5% of Fusarium and 15.9%
of Penicillium (71.7%). In white maize, the incidence of Aspergillus was 44.6%, 6%
of Fusarium and 10.4% of Penicillium (61%). Under field conditions, yellow maize
showed higher incidences of Aspergillus (3.1%), Fusarium (76.9%) and Penicillium
(11.6%) than white maize (2.4, 63.6 and 7.9%, respectively). Yellow maize hybrids
DK-697 and DK-1060; Garst 8222, 8285 and 8288 and Golden Acres 8112, 8311 and
8460 showed the highest micotoxigenic fungi incidences, while white maize hybrids
Tigre, H-437, H-436 and Asgrow 7573 exhibited the lowest incidences. White grain
hybrids UAP-1851, DK-2010 and Asgrow 7573 did not show incidence of Aspergilli.
Results indicate that among the potentially micotoxigenic fungi detected in white or
yellow maize stored at northern Tamaulipas, Aspergillus (A. flavus, A. niger and A.