IFEVA   02662
INSTITUTO DE INVESTIGACIONES FISIOLOGICAS Y ECOLOGICAS VINCULADAS A LA AGRICULTURA
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
GENOTYPIC VARIATION FOR BRITTLE-SNAP SUSCEPTIBILITY IN MAIZE (ZEA MAYS L.): PHENOTYPING OF STALK BREAKAGE AND RELATED TRAITS IN A RILS POPULATION
Autor/es:
RODRIGUEZ, J.G.; KUSSROW, N.; PIRCHI, I.L.; CIRILO, A.G.; CERRI, A.M.; OTEGUI, M.E.
Lugar:
Bento Goncalves
Reunión:
Congreso; VI International Crop Science Congress; 2012
Institución organizadora:
International Crop Science Society
Resumen:
Winds stronger than 45 m s-' are known to cause severe brittle-snap of maize (Zea mays L.), with
stalks breaking near the uppermost ear node, particularly in crops undergoing active stem
elongation immediately before anthesis. Early studies on this trait focused on genotypic variation
among commercial hybrids and the effect of management practices. They concluded that the best
strategy is to plant hybrids less prone to breakage, but breeding against this constrait is limited by
the lack of accurate methods for simulating brittle-snap. The aim of this work was to study the
genotypic variation in maize susceptibility to stalk breakage. Primarily, for providing robust data for
QTL analysis, and additionally for evaluating its relationship with several morphometric traits. These
traits were plant height to the uppermost ear and to the uppermost collar, estimated stem volume at
ear and uppermost collar heights, and stalk diameter at ground level. We phenotyped mentioned
traits for a collection of 180 recombinant inbred lines (RILs) derived from two contrasting parental
inbreds (B100: American semident; LP2: Argentine flint). Inbreds were sown in the field at three
different sowing dates (14, 18 and 23 Nov, 2011) for avoiding the confounded effect of their variation
in time to anthesis (surveyed during 2009-2010). The experimental layout was a completely
randomized block design with two replicates. Stand density was 7 plants m-2, and plots had 10.5
m2. A severe wind storm (winds > 45 m s-') took place on 23-Jan-2012. It was immediately before
anthesis of the experiment, which spanned between 24-Jan and 7-Feb. Stalk breakage ranged
between 0 (28% of inbreds) and >50% damage (1.1% of inbreds, with maximum of 55.6%), it was
not normally distributed