Genetic Resistance to Powdery Mildew in Strawberry

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Material Information

Title:
Genetic Resistance to Powdery Mildew in Strawberry Response to Selection and Wild Species Characterization
Physical Description:
1 online resource (134 p.)
Language:
english
Creator:
Kennedy, Colleen
Publisher:
University of Florida
Place of Publication:
Gainesville, Fla.
Publication Date:

Thesis/Dissertation Information

Degree:
Doctorate ( Ph.D.)
Degree Grantor:
University of Florida
Degree Disciplines:
Horticultural Sciences
Committee Chair:
WHITAKER,VANCE M
Committee Co-Chair:
OLMSTEAD,JAMES W
Committee Members:
FOLTA,KEVIN M
PERES,NATALIA A R

Subjects

Subjects / Keywords:
ananassa -- chiloensis -- fragaria -- virginiana
Horticultural Sciences -- Dissertations, Academic -- UF
Genre:
Horticultural Sciences thesis, Ph.D.
bibliography   ( marcgt )
theses   ( marcgt )
government publication (state, provincial, terriorial, dependent)   ( marcgt )
born-digital   ( sobekcm )
Electronic Thesis or Dissertation

Notes

Abstract:
Powdery mildew (PM) of strawberry is a ubiquitous, wind-spread disease caused by the obligate parasite Podosphaera aphanis.  To control PM, multiple applications of fungicides are necessary each season, and none of the major cultivars in Florida have high levels of resistance.  Many breeders have turned to wild relatives in search of beneficial traits such as disease resistance. In strawberry, the wild octoploid species Fragaria virginiana and F. chiloensis are fully interfertile with the cultivated species, F. × ananassa, and are therefore potential sources of resistance.   One objective of this study was to screen wild strawberry accessions for resistance to PM.  In 2010-11 and 2012-13, wild accessions, cultivars and controls were planted.  Although there was a significant year × genotype effect, some taxa showed high levels of resistance that were consistent across years.  A second objective of this study was to observe response to selection through divergent selection and to estimate genetic parameters for PM in the University of Florida breeding population.  In 2010, individuals from seven bi-parental crosses arising from 11 different parents were included in a field trial in which clonally replicated seedlings were evaluated visually for percent coverage of PM.  Heritabilities for PM score were H2=0.50±0.08 and h2=0.40±0.39 for the base population.  After the second round of selection in the resistant population, no additive variance was detected, indicating that alleles for PM resistance had become fixed.  Because Florida can serve as a model system for annualized winter and spring production worldwide, a third objective of this study was to characterize wild strawberry accessions for mortality and flower and runner production.  There are wild accessions that would be attractive for inclusion in germplasm development.  In addition to producing many flowers and few runners, they had low mortality and had resistance to PM.  Some accessions are highly susceptible to PM, and this must be considered when utilizing these genotypes.  Additionally, moderate to high heritability estimates and clear response to selection indicate that PM is genetically controlled through mostly additive effects and selection of parents based on field trials with natural inoculum should result in good progress toward more resistant cultivars.
General Note:
In the series University of Florida Digital Collections.
General Note:
Includes vita.
Bibliography:
Includes bibliographical references.
Source of Description:
Description based on online resource; title from PDF title page.
Source of Description:
This bibliographic record is available under the Creative Commons CC0 public domain dedication. The University of Florida Libraries, as creator of this bibliographic record, has waived all rights to it worldwide under copyright law, including all related and neighboring rights, to the extent allowed by law.
Statement of Responsibility:
by Colleen Kennedy.
Thesis:
Thesis (Ph.D.)--University of Florida, 2013.
Local:
Adviser: WHITAKER,VANCE M.
Local:
Co-adviser: OLMSTEAD,JAMES W.
Electronic Access:
RESTRICTED TO UF STUDENTS, STAFF, FACULTY, AND ON-CAMPUS USE UNTIL 2014-12-31

Record Information

Source Institution:
UFRGP
Rights Management:
Applicable rights reserved.
Classification:
lcc - LD1780 2013
System ID:
UFE0046109:00001