2 research outputs found
Winter cereal root growth and abovegroundâbelowground biomass ratios as affected by site and tillage system in dryland Mediterranean conditions
Background and aims Understanding the interaction
between crop roots and management and environmental
factors can improve crop management and agricultural
carbon sequestration. The objectives of this study
were to determine the response of winter cereal root
growth and abovegroundâbelowground biomass ratios
to tillage and environmental factors in the Mediterranean
region and to test an alternative approach to
determine root surface area.
Methods Winter cereal root growth and biomass ratios
were studied in three sites with different yield potential
according to their water deficit (high yield potential,
HYP; medium yield potential, MYP; low yield potential,
LYP) in the Ebro Valley (NE Spain). At all sites,
three tillage systems were compared (conventional
tillage, minimum tillage, no-tillage (NT)). Root surface
density (RSD), soil water content, yield components,
and grain yield were quantified and shoot-toroot
and grain-to-root ratios were calculated. RSD
was measured with the use of image analysis software
comparing its performance to a more common intersection
method.
Results Significant differences on RSD between sites
with different yield potential were found being the
greatest at the HYP site and the lowest at the LYP
one. Shoot-to-root ratio was 2.7 and 4.6 times greater
at the HYP site than at the MYP and LYP sites, respectively.
Moreover, the grain-to-root ratio was significantly
affected by site, with a ratio that increased with
yield potential. Tillage had no significant effects on
RSD at any of the sites studied; however, tillage did
affect grain yield, with NT having the greatest yields.
Conclusions This study shows that in theMediterranean
dryland agroecosystems, winter cereals relative aboveand
belowground biomass growth is strongly affected by
the yield potential of each area. NT in theMediterranean
areas does not limit cereal root growth and leads to
greater grain yields. A highly significant linear relationship
(P<0.001; r2 0.77) was observed between the root
surface values obtained with the free-software image analysis method and the most common intersection
method, showing it to be a reliable method for quantifying
root density.This work was supported by the ComisiĂłn Interministerial de Ciencia y TecnologĂa of Spain (grants AGL2007-66320-CO2-01 and AGL2010-22050-CO3-01/02)