INTRODUCTION
TO RESEARCH PROJECT:
Premature separation
(abscission) of flowers and fruit reduces the potential yield of many crops.
We study the molecular and genetic mechanisms involved in abscission with
the goal of engineering plants possessing beneficial abscission characteristics
that not only increase yield but also reduce harvesting costs. Ethylene
is a plant hormone that controls many aspects of abscission and senescence.
Ethylene physiology and signal transduction are an important part of our
abscission studies.
Bright-field
micrograph of a toluidine stained thin longitudinal section from the upper
abscission zone of a bean leaf after 48 h exposure to 25 uL/L ethylene
in air. vb = vascular bundle.
Combination
of Figures 1 and 2. A, Bright-field micrograph of a toluidine stained thin
longitudinal section from the upper abscission zone of a bean leaf after
48 h exposure to 25 uL/L ethylene in air. vb = vascular bundle. B, Detection
of cellulase mRNA in the abscission zone by in-situ hybridization. Dark-field
micrograph of thin longitudinal section. Sections were hybridized to 35S-labelled
antisense (complementary) strand RNA transcripts of a bean abscission cellulase
cDNA. Hybridization signals are seen as bright, light-reflecting silver
grains.
histochemical
staining for TAPG4:GUS expression in pistils and selected abscission
zones from 4-4 transformants. Explants were exposed to ethylene for 48h
and histochemically stained for GUS activity. (from: Plant Physiology (2000),
123:869-881).