INVESTIGADORES
BALZARINI Monica Graciela
artículos
Título:
Morpho-physiological traits associated with maize crop adaptations to environments differing in nitrogen availability.
Autor/es:
CIRILO A; DARDANELLI J; BALZARINI M; ANDRADE F,; CANTARERO M,; LUQUE S.; PEDROL M.
Revista:
FIELD CROPS RESEARCH
Editorial:
ELSEVIER SCIENCE BV
Referencias:
Año: 2009 vol. 113 p. 116 - 124
ISSN:
0378-4290
Resumen:
The use of genotypes with improved performance for nitrogen (N) capture and use would be of great
benefit through reducing production costs and pollution risks in maize cropping. The identification of
morpho-physiological traits responsible for a better behavior in a target N environment is useful for
cultivar selection, and become crucial for maize breeding improvement. This study analyzed, in a set of
Argentinean commercial hybrids of maize, the grain yield (GY) variability in response to soil N
availability at several locations representative of the main maize production region of Argentina during
20032004 growing season. The objectives of this work were to: (i) detect environmental groups for GY
responses, (ii) identify morpho-physiological traits that were associated to winner genotypes in each
detected environmental group, and (iii) assess genetic correlations between those traits. To generate
more variation in soil N availability two N-fertilizer rates were applied in each experimental site (0 and
250 kg N ha_1, except for Balcarce where only 250 kg N ha_1 was tested). Morpho-physiological traits
included in the analysis were related to N and radiation capture, use and partitioning, plant architecture,
and leaf senescence. Grain yield components were also included. As expected, environment (E) effect
explained the higher portion of GY variation (i.e., 82%), but genotype (G) and G _ E interaction (GE) also
significantly contributed (i.e., 9% each). Three environmental groups for GY were identified according to
N availability. Morpho-physiological traits related to resource capture, use, and partitioning during the
post-silking period are proposed as desirables for broad adaptation. In turn, a high N partitioning to
grains after silking was associated with good hybrid behavior under high N availability and warm
climate. On the other hand, a better grain yield performance when N became more limited appeared
strongly related to an efficient canopy to sustain resource capture up to maturity. More studies are
required in a wide range of environments to confirm identified traits and underlying physiological
mechanisms. Nevertheless, our findings highlight the existence of differences in ideal plant-type for
environments differing in N availability to be considered in maize breeding programs