Research identifying and measuring the genetic mutations of selected grapevines when exposed to environmental stresses has won Lincoln University PhD student Darrell Lizamore the David Jackson prize for 2013.
The $1,500 award recognises wine industry related research that displays both academic rigour and innovative thinking, but must also show how the findings could lead to a beneficial change within the industry.
Darrell’s research centres on the mutations within grapevines caused by mobile DNA sequences called transposons; a segment of DNA which has the ability to replicate and insert itself into a new position within the same or another chromosome.
Most inter-clonal diversity within grapevines is caused by transposons and is unwelcome or harmful, yet, while in most cases the plant’s internal system prevents the appearance of new mutations, this system can be compromised under stressful conditions.
Darrell’s research looked at measuring which kind of stresses result in transposon expression and to what degree, with examples of these induced stresses being such things as UV exposure, temperature shocks, and exposing plant tissue to microorganisms such as bacteria or fungi.
Complications with the research lay in finding a method to effectively measure the new transposons; a problem made all the more difficult when considering the high background of ancient transposons that comprise over 40 percent of the grapevine genome.
To overcome this problem, transposons were tagged using a fluorescent dye, after which the tagged DNA was sorted using a capillary DNA sequencer. From there, transposons could be grouped according to their particular type and position within the vine’s DNA; thereby ensuring new transposons could be identified.
This ingenious method aside, Darrell’s work has gone on to form the basis of a new project in which large populations of Pinot noir and Sauvignon blanc are being produced carrying new transposon insertions.
The motivation for this project is that, while the international wine industry uses grape type as a means of marketing their products and as a marker of style and quality, like any other market there is a need to find ways to develop and differentiate. Darrell’s research makes use of naturally occurring transposons to generate and identify vines with altered characteristics.
Darrell was awarded the David Jackson prize at the David Jackson Dinner held on Friday 24 May, in association with Wines of Canterbury.