MSc Final Oral Examination: Jennifer Marsella


Interested Members of the University Community are invited to attend the Final Oral Examination for the Degree of Master of Science of Jennifer Marsella of the Department of Plant Agriculture

Date: Monday, June 10th 
Time: 1:00 PM
Location: Room 202, Crop Science Building

Thesis Title: Evaluation of Photoperiod Sensitivity in Spring Canola (Brassica napus L.)

Advisory Committee:   
Dr. Istvan Rajcan, Advisor
Dr. Hugh Earl
Dr. Jay Patel

Examination Committee
Dr. Peter Pauls, Chair         
Dr. Istvan Rajcan
Dr. Laima Kott
Dr. Jay Patel


Canola, Brassica napus L., is a facultative long day plant in which variation exists in photoperiod sensitivity allowing for plants to flower at the same time regardless of day length. The objectives of this research were to: 1) evaluate the flowering time of parents of Doubled Haploid (DH) populations that were used for genetic studies under 12-, 14- and 16-hour day length under controlled environmental conditions; 2) evaluate DH populations for days to flower under short- and long-day field environments; and 3) identify putative QTL involved in photoperiod insensitivity in B. napus. Significant differences in flowering time were identified between photoperiod sensitive and insensitive parents of the population grown under 12-hour and 16-hour day length. However, differences were inconsistent between 12- and 14-hour and, 14- and 16-hour day lengths.  Under field conditions, transgressive segregation was observed at the short-day field location.  DHs were identified from each population that flowered at the same time under both long- and short-day conditions.  A putative QTL was detected on linkage group C8 associated with photoperiod in which the allele from the photoperiod insensitive parent decreased days to flower.  The position of the QTL may coincide with a homologue of a gene for a transcription factor previously reported in A. thaliana, which is involved in chlorophyll biosynthesis and light harvesting complexes.  The results of this thesis provide insight into photoperiod insensitivity as an important goal for canola breeders developing varieties with broad adaptation.