| Material Information
||Susceptibility of 12 Dieffenbachia cultivars to Xanthomonas campestris pv. dieffenbachiae
||CFREC-Apopka research report
||2 p. : ; 28 cm.
||Chase, A. R ( Ann Renee )
Henny, R. J
Central Florida Research and Education Center--Apopka
||University of Florida, IFAS, Central Florida Research and Education Center-Apopka
||Place of Publication:
||Dieffenbachia -- Diseases and pests -- Florida ( lcsh )
Xanthomonas campestris -- Control -- Florida ( lcsh )
||government publication (state, provincial, terriorial, dependent) ( marcgt )
non-fiction ( marcgt )
||Statement of Responsibility:
||A.R. Chase and R.J. Henny.
| Record Information
||University of Florida
||All rights reserved by the source institution and holding location.
||oclc - 70552740
The publications in this collection do
not reflect current scientific knowledge
or recommendations. These texts
represent the historic publishing
record of the Institute for Food and
Agricultural Sciences and should be
used only to trace the historic work of
the Institute and its staff. Current IFAS
research may be found on the
Electronic Data Information Source
site maintained by the Florida
Cooperative Extension Service.
Copyright 2005, Board of Trustees, University
0 R Susceptibility of 12 Dieffenbachia Cultivars to Xanthomonas
oB campestris pv. dieffenbachiae
A.R. Chase and R.J. Henny
University of Florida, IFAS
Central Florida Research and Education Center Apopka
CFREC-Apopka Research Report, RH-89-6
This study was conducted to determine the sensitivity of twelve
Dieffenbachia cultivars to inoculation with the bacterium Xanthomonas
campestris pv. dieffenbachiae. Such information may be of value to growers
responsible for monitoring these crops for potential disease outbreaks.
A. Dieffenbachia Cultivars 12 different Dieffenbachia cultivars
(Table 1), consisting of commercial cultivars and unreleased
CFREC-Apopka hybrids, were inoculated with Xanthomonas in.foUr----.
separate tests initiated on:
Test No. Initiated Li'rai7
B. Growth Medium Plants were grown from tip cuttings rooted in
Vergro Container Mix A (Verlite Co., Tampa, FL).
C. Light and Temperature Light levels varied between 1650 and
2400 ft-c (75-80% shade) in shaded greenhouses while the
temperature range was 65-900F.
D. Inoculation Plants were artificially inoculated with a liquid
suspension of X. campestris pv. dieffenbachiae. This was done
under high humidity conditions provided by overhead mist to help
promote disease development.
E. Disease Severity This was rated in each test between 2 and 4
weeks after inoculation using the following scale:
Rating Disease Symptoms Cultivar Susceptibilit
1 No disease symptoms None
2 Tiny lesions scattered across Slight
the leaves at random
3 Appearance of water-soaking Moderate
around the expanding lesions,
also marginal necrosis and
4 All of the above symptoms plus High
1Professor of Plant Pathology, and Professor of Plant Genetics,
respectively. Central Florida Research and Education Center Apopka,
2807 Binion Road, Apopka, FL 32703.
Table 1. Susceptibility of 12 Dieffenbachia cultivars to Xanthomonas
campestris pv. dieffenbachiae.
Cultivar Average disease Overall
name rating susceptibility
Triumph 2.4 a
Victory 2.2 ab moderate
Hybrid 59301 1.9 bc
Starry Nights 1.9 bcd
Compacta 1.8 cd
Hybrid 65801 1.8 cd
Camille 1.8 cd slight
Memoria-Corsii 1.8 cd
Star White 1.6 cd
Bausei 1.5 d
Hybrid 649011 1.1 e very
Tropic Star 1.1 e resistant
zThe results presented are
between November 29, 1988
letters are significantly
the means from 4 separate experiments conducted
and May 22, 1989. Means followed by different
different based on Duncan's multiple range test,
Dieffenbachia cultivars Triumph and Victory were most susceptible to
infection by Xanthomonas campestris pv. dieffenbachiae whereas Tropic Star
and Hybrid 649011 showed almost no disease symptoms. None of the cultivars
tested in this study could be classified as highly susceptible to the
pathogen. However, producers of the more susceptible cultivars should be
aware of their disease potential.