Event / Evento: II Workshop on Sugarcane Physiology for Agronomic Applications Speaker / Palestrante: Rafael V. Vasconcelos (University of Campinas - Unicamp) Date / Data: Oct, 29-30th 2013 / 29 e 30 de outubro de 2013 Place / Local: CTBE/CNPEM Campus, Campinas, Brazil Event Website / Website do evento: www.bioetanol.org.br/sugarcanephysiology

1. CROP
PHYSIOLOGY
OF
SUGARCANE:
ASSESSING
THE
PHYSIOLOGICAL
ROLE
OF
ROOTS
Rafael
V.
Ribeiro
University
of
Campinas
(Unicamp),
Institute
of
Biology,
Dept.
Plant
Biology,
Campinas
SP,
Brazil.
E-­‐mail:
rvr@unicamp.br
Recent
results
of
research
on
sugarcane
physiology
were
presented,
taking
into
account
the
role
of
root
system
under
water
limiting
conditions.
Considering
plants
growing
in
rhizotrons
and
nutrient
solution,
some
interesting
responses
of
sugarcane
varieties
were
revealed.
As
key
findings,
our
data
indicate
that
classical
growth
analysis
can
reveal
the
degree
of
drought
resistance
more
properly
than
physiological
evaluations.
In
addition,
high
yield
varieties
are
not
necessarily
sensitive
to
drought
stress.
The
expected
trade-­‐off
between
plant
biomass
production
and
drought
tolerance
was
not
found
in
our
study,
suggesting
that
we
may
find
sugarcane
varieties
with
high
yield
and
tolerance
against
environmental
constrains.
In
general,
low
phenotypic
plasticity
is
associated
with
less
sensitivity
to
water
deficit,
considering
both
morphological
and
physiological
plasticity.
From
our
study
under
nutrient
solution,
we
noticed
that
the
drought
resistant
genotype
is
able
to
delay
drought
effects
on
leaf
physiology,
showing
less
sensitivity
of
root
hydraulic
conductance
and
photosynthesis
to
water
deficit.
Root
aquaporins
play
an
important
role
in
water
relations,
with
the
response
to
water
deficit
being
genotype-­‐dependent.
However,
increased
aquaporin
expression
(PIPs)
in
roots
at
the
early
stages
of
water
deficit
is
not
directly
related
to
improvements
of
water
transport
through
root
system.