Page 31 - CSHS 2022 Book of Abstracts - 2022-08-22 web version

CSHS 2022 Conference

(PO.3) Phellem Morphology and Polyphenols Analysis of Tuber Skin Defects on Dark Red
Norland
Manlin Jiang , Tracy Shinners-Carnelley , Darin Gibson , Debbie Jones , Jyoti Joshi , Gefu Wang-
3
1*
1
3
2
Pruski
1
1. Faculty of Agriculture, Dalhousie University, Bible Hill, NS; 2. Research, Quality & Sustainability, Peak of the Market,
Winnipeg, MB; 3. Gaia Consulting Ltd., Newton, MB
________________
Dark Red Norland is an important potato cultivar in the fresh market mainly due to its attractive bright, red color
and good yield. However, some skin defects can negatively influence the tuber skin quality and marketability. Silver
patch, surface cracking, and russeting are the three skin defects studied in this project. A three-year field trial was
conducted by Peak of the Market in Manitoba, Canada. Heat stress was applied in different tuber growing stages
under both irrigation and rainfed conditions. Results showed that irrigation reduced soil temperature, increased
total yield, and reduced the severity of surface cracking. Microscopy imaging analysis demonstrated that tubers from
the rainfed trials formed higher numbers of suberized cell layers than that of irrigated. Surface cracked and silver
patched skins had more suberized cell layers than the normal skins. Also, significantly higher amount of total
polyphenols was found in silver patched skins with a mean of 76.85 mg gallic acid equivalents (GAE)/100 g fresh
weight (fw) than that of normal skins (69.12 mg GAE/100 g fw). Silver patched skins also found to have significantly
less total anthocyanin with an average of 0.053 mg C3GE/100 mg fw than that of normal skins (0.073 mg C3GE/100
mg fw). The outcome of this study provided better understanding of the environmental effect causing these skin
defects, which could potentially be used to establish strategies to improve skin quality and minimize market loss.

(PO.4) Fighting against potato greening
Louis de Gonzague Sebareze 1,2* , Mohsin Zaidi , Christian Lacroix , Fatima Mitterboek , Benoit
2
3
1
Bizimungu , Bourlaye Fofana
3
1
1. AAFC, Charlottetown, PEI; 2. University of Prince Edward Island, Charlottetown, PEI; 3. AAFC, Fredericton, NB
________________
Potato is the largest vegetable crop in Canada, with an export value of $1.8B in 2019. As a major food source, potato
nutritional quality and safety are critical for the public health. Potato greening, also known as potato sunburn,
causes 2-3% loss at the farm gate and up to 17% during postharvest and retail storage. It results from a de novo
synthesis of chlorophyll in the cortical parenchyma cells under the periderm after light exposure and leads to a
simultaneous formation of toxic steroidal glycoalkaloids (SGAs). Whereas chlorophyll itself is not a health hazard,
SGAs are toxic to humans and animals. Development of potato cultivars that are resistant to light-induced greening
is a viable strategy for an economic and environmental sustainability. We will present and discuss our approach and
preliminary results towards an understanding of the tuber greening phenomenon in potato.

31