Barnes, B.D., Kopecký, D., Lukaszewski, A.J., Baird, J.H.
CROP SCIENCE
54:
355-365,
2014
Keywords:
AGB, aboveground biomass; CIMIS, California Irrigation Management Information System; ETo, reference evapotranspiration; FL, Festulolium; MAP, months after planting; MF, meadow fescue; NDVI, normalized difference vegetation index; PR, perennial ryegrass; PVC, polyvinyl chloride; TF, tall fescue; UCR, University of California, Riverside
Abstract:
Broadening the genetic pool of crop species by
wide hybridization is an established practice in
plant breeding. Festuca × Lolium hybrids (Festulolium
[FL]) are already established as commercial
forage grasses around the world. By
recurrent selection for drought and heat tolerance
we developed turf-type populations of FL
with increased stress tolerance. This improvement
appeared associated with the presence
of an introgression of meadow fescue [Festuca
pratensis (Huds.) P. Beauv.] chromatin on
chromosome 3 of perennial ryegrass (Lolium
perenne L.). To determine if deeper and more
extensive root characteristics were responsible
for increased stress tolerance, a greenhouse
study was conducted on FL both with
and without the introgression, parental controls,
and tall fescue (F. arundinacea Schreb.). In two
experiments in sand-filled tubes, meadow fescue
(MF) produced the deepest roots, most
root biomass, and highest root:shoot ratio; FL
and perennial ryegrass (PR ) were intermediate
while tall fescue (TF) ranked at or near the bottom
for these traits. The results suggested that
drought tolerance in FL was not a consequence
of altered root depth or biomass. In a 2-yr field
study of drought tolerance at deficit irrigation
(50–70% ETo), turf quality of FL and PR was significantly
greater compared to the fescues; FL
populations appeared to offer greater turf quality
during drought conditions than the fescues,
but they did not differ from PR itself. In only 1
yr were mature TF stands equal to PR and FL
in recovery rates. While the actual mechanism
is still obscure, it appears that, with additional
breeding and selection, FL hybrids have the
potential to withstand water deficit at least as
well as TF, while providing better turf quality.
Fulltext: contact IEB authors
IEB authors: David Kopecky
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