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Selección entre y dentro de familias de hermanos completos de maíz en Chiapas, México

ABSTRACT Entre 2002 y 2005 se hicieron tres ciclos de selección recurrente de familias de hermanos completos en tres variedades de maíz (Zea mays L.) que se cultivan comercialmente en Chiapas: ¿V-424¿ (de ciclo precoz), ¿V-534¿ (de ciclo intermedio) y ¿V-526¿ (de ciclo tardío). El objetivo fue incrementar sus rendimientos de grano, y a la vez mantener el fenotipo y madurez de cada población. Durante los ciclos agrícolas de temporal o secano de 2005 y de riego de 2006 se evaluaron en Ocozocoautla y Villaflores, Chiapas, México, a 14 variedades experimentales formadas de los ciclos uno, dos y tres de cada población, más su población original. Se encontraron diferencias significativas entre localidades y entre variedades para las tres poblaciones en el rendimiento de grano, y la interacción localidades x variedades sólo fue significativa para la población ¿V-534¿; las variedades experimentales ¿V-424 Coita C3¿, ¿V-534 Coita C3¿ y ¿V-526 Villaflores C3¿ superaron en rendimiento a las respectivas variedades originales, sin cambiar su fenotipo y madurez, con respuestas de 3.0 %, 5.2 % y 4.2 % por ciclo de selección, respectivamente.

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Jun 16, 2014