Analysis of the Outcrossing Ratio of German Chamomile (Matricaria recutita L.) using SSR-markers
Date
2020-05-26
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
ORCID
Type
Thesis
Degree Level
Masters
Abstract
German chamomile (Matricaria recutita L.) is one of the most ancient and widely used medicinal
plant species. Plant breeding efforts for desired agronomic traits have existed for over sixty years;
however, the breeding programs for chamomile are small in comparison to other crop plant species. The
objective of this thesis was to examine the variability of chamomile’s outcrossing ratio based upon
multiple environmental factors in order to provide a basic understanding of pollination biology to inform
the breeding of chamomile. Two studies were conducted to achieve this objective. The first study
evaluated the outcrossing ratio at multiple geographical locations throughout central Germany. The
second study evaluated greenhouse compared to field conditions, as well as, potential temperature effects
on the outcrossing ratio. Chamomile exhibited a wide range of outcrossing frequencies in the crosses
regardless of both location and ploidy. The results did not show a statistical difference between
geographical locations; however, in all crosses there appeared to be an effect associated with crossing
direction. In many crosses, the frequency of outcrossed progeny was considerably higher in one cross
direction than the other. The greenhouse and field comparison could not be made due to progeny
germination difficulties. The greenhouse crosses could have been negatively affected by poor pollination,
seed dormancy, and unfavorable temperature conditions during germination. Although this study had
technical issues, and the outcrossing ratio could not be analyzed as expected, valuable knowledge was
gained for the direction of future research in chamomile.
Description
Keywords
German chamomile, Matricaria recutita
Citation
Degree
Master of Science (M.Sc.)
Department
Plant Sciences
Program
Plant Sciences