Capital Press, OR
02-02-07
Grape researcher discusses manipulation of bud dormancy
By JOE NAIMAN
Freelance Writer
Professors and other South Dakota State University researchers who visit San
Diego for conferences find that in San Diego "SDSU" refers to San Diego State
University and not their own university in Brookings.
But when Anne Fennell came to San Diego for the International Grape Genome
Project Workshop Jan. 14, the weather was more typical of South Dakota than
San Diego.
The weather made Fennell's presentation suitable for San Diego County as well
as South Dakota since her presentation, titled "Functional Genomics of Bud
Endodormancy Induction in Grapevines," focused on the ability to manipulate
bud dormancy to increase vine crop production in cold-weather areas.
Fennell, the presenting author, is affiliated with the Horticulture, Forestry,
Landscape and Parks Department of South Dakota State University, as are
project contributors Kathy Mathiason, Jerome Grimplet and Doug He.
Contributors Grant Cramer and Laurent Deluc are researchers at the University
of Nevada's Department of Biochemistry (the University of Nevada is in Reno),
Karen Schlauch provided work through the Department of Genetics and
Genomics of Boston University's School of Medicine, and Julie Dickerson
contributed on behalf of the Virtual Reality Applications Center of Iowa
State University in Ames, Iowa.
Bud dormancy is an adaptive strategy in grapevines that allows for survival
through drought, high and low temperatures and freeze dehydration stress. While
that dormancy trait allows for crop survival, it also limits the geographic range
and yield of grapes. Researching the biological components involved in bud
dormancy is intended to improve selection and breeding and to improve cultural
practices for dormancy management in existing grape stock.
"Our major focus is to gain a better understanding of the regulation of bud
dormancy," Fennell said.
She said bud dormancy has become more important as areas in which grapes
are grown have expanded and as climate change has become more relevant.
"It's also very critical to survival with the lower temperatures," she said.
Fennell and her research partners used an integrated functional genomic
approach to a genetic vitis system with differences in endodormancy induction.
They used hybrids of Vitis riparia, which is grown in Manitoba, and Vitis seyval,
which is grown in South Dakota and Minnesota. Vitis riparia will go dormant upon
shorter days (either in nature or in a light-controlled indoor laboratory
environment), while more climate-related stimulation is required to induce
dormancy in Vitis seyval.
"What we will be doing is we'll be taking a systems biology approach," Fennell
said.
Short and long photoperiods were used to induce endodormancy or maintain
paradormancy in responsive and non-responsive genotypes, and studies in agematched buds during endodormancy and paradormancy phases separated bud
maturation response from endodormancy regulation. Buds were harvested at
seven time points between one and 42 days.
"We're building from the same tissue," Fennell said. "We're using the same set of
tissue all the way through."
The researchers relied on various profiling methods and used integrated
bioinformatics tools to convert three separate data bases into an understanding
of bud development and dormancy induction. "That requires a lot of bioinformatic
information," she said.
The vitis data was mapped against the data for arabidopsis, a plant whose
genome has been completed, to create a pathway model, verify the data,
develop models for bud endodormancy and export the data into analysis
software.
"The key thing is the grape metabolic pathway mapping," Fennell said.
That makes it easier to visualize data, which will allow for identification of
pathways specific to bud dormancy. Future work will identify relationships
between bud dormancy and features such as abiotic stress responses.