The "South Grapes"

North Dakota State University's First Grapevine Mapping Population*

*These experimental lines and progeny of them are not currently on the market nor are they available for sale.

Three Main Parents

ND.054.27

(‘Frontenac gris’ × ‘Adalmiina’)

  • Large berries, large cluster.

  • Low acid.

  • Cold-tolerant over many years at Fargo test site.

ND.213

(C14 × ‘Alpenglow’)

  • Moderate size berries, large cluster.

  • Low acid

  • Cold-tolerant over many years at Fargo test site.

SKND.009.41

(Saskatchewan V. riparia accession Riparia L × V. vinifera ‘Csabagyöngye’)

  • Moderate cluster.

  • Moderate acidity, muscat character, herbaceousness absent.

  • Cold-tolerant over many years at Fargo test site.

Two Birds-One Stone

Population Crossing Scheme

A diallel cross was constructed among three of the best NDSU-GGEP accessions for cold-hardiness, yield characteristics, and wine potential based on early evaluations by John Stenger, Collin Auwarter, Harlene Hatterman-Valenti, and the HVC Research Team. A total of 1064 S0/F1 progeny were field planted.

The mating structure enables Genome Wide Association Studies (GWAS) and traditional, bi-parental mapping based on the of three sub-populations formed.

Also, because the segregating seedlings in these populations vary widely for traits of interest (flavor, acid, ripening time, yield components), we are able to simultaneously use the detailed phenotypic and genotypic data for selection of new wine grape genotypes for the region.

A Brief History of the "South Grapes"

2016

  • In the summer of 2016, John Stenger, Collin Auwarter, and other members of the HVC Research Team conducted nearly 200 unique crosses to form the populations planted in 2017.

2017

  • Germinated in winter and spring of 2017, >4,600 grapevines from 79 selected sub-populations were planted in a 1.34 acre field by John Stenger, Collin Auwarter, Nickolas Theisen, Razi Ibrahim, and Andrej Svyantek during June 2017. These individuals were developed for applied research and germplasm enhancement objectives.

2018

  • Grapevines were trained to single trunks in the summers of 2018 and 2019; moderate to severe damage occurred as the result of rabbit herbivory.

2019

  • The first harvest screening and selection for flavor, disease susceptibility, and fruit composition was conducted by Matthew Brooke, Bülent Köse, Ikbal Tatar, Binu Rana, Collin Auwarter, Andrej Svyantek and the HVC Research Team.

  • The three large sub-populations forming the "South Grapes" mapping population were un-selected, maintaining informative segregants.

  • Leaf samples were submitted by Matthew Brooke, Ikbal Tatar, Andrej Svyantek, and the HVC Research Team for genetic sequencing via newly developed rhAmpSeq technology as part of VitisGen2. Individuals were culled based on presence/absence of alleles for disease resistance traits.

2020

  • Venkateswara Rao Kadium enrolled at NDSU to study grapevine breeding. The "South Grapes" serves as his major thesis project.

  • Additional leaf samples were submitted for rhAmpSeq by Bülent Köse, Sarah Bogenrief, Venkateswara Rao, and Andrej Svyantek as part of VitisGen2.

  • Leaf samples of the core populations were submitted for Genotypying by Sequencing (GBS) by Venkateswara Rao, Sarah Bogenrief, Zhuoyu Wang, and Andrej Svyantek through a collaboration with Dr. Xuehui Li.

  • Screening of fruit composition was conducted for all fruiting individuals on three dates to examine ripening progress across time.

  • Detailed screening of phenology (budbreak, flowering, canopy development, veraison, and dormancy acclimation) and cold-hardiness (as monitored via Differential Thermal Analysis [DTA]) was conducted by Venkateswara Rao with help from the HVC team.

Phenotypic Data Collected

Examining the three main sub-populations, Venkateswara closely monitored multiple traits. This data contributes to his Thesis research towards identification of informative QTL for environmentally adaptive traits and fruit quality.

Simultaneously, individuals with high-performance are being propagated for distribution to the North Dakota grape growing community.

Bud Break

Bud break is the appearance of green tissue between bud scales.

Initial bud break was observed around mid-May of 2020.

Timing of different stages of bud development such as bud swelling, wooly bud formation, beginning and end of bud burst were monitored every 3-4 days using BBCH scale.

Shoot Development

Leaves unfolded from the broken buds in the following weeks.

Timing of number of leaves opened were observed using the BBCH scale.

Flowering

We observed initial compact inflorescence development during early June, later they differentiated leads to loosening of flowers. Shortly after, flower hoods (calyptra) started detaching from the receptacle.

These changes in flower development were scored every 2-3 using the BBCH scale.

Veraison

Changes in berry color and texture were monitored every 2-3 days interval using the BBCH scale.

Fruit Composition (Ripening in Time)

In 2020, 255 fruiting genotypes were harvested at three different times in August-September across ~10 days interval to measure brix, pH and total acidity.

Dormancy Acclimation and

Cold-Hardiness

After harvest, fruiting genotypes were studied for dormancy wood acclimation traits from Sept. 11 until Oct. 15 for a total of 6 phenotyping events.

Traits monitored included: Number of periderm encompassed nodes, mature nodes, and total nodes from random shoots selected (4 per genotype) during each phenological rating event.

Powdery Mildew Tolerance

Powdery mildew infection rate varied throughout the planting.

Disease infection ratings were scored using an ordinal scale (1-5).

Downy Mildew Tolerance

Downy mildew infection rate also varied throughout the planting.

Disease infection ratings were scored using ordinal scale (1-5).

2,4-D Tolerance

Some genotypes expressed 2,4-D injury due to drift from the surrounding fields.

Ratings were taken to identify whether any genotypic variance for 2,4-D tolerance exists within the populations.