Tolga
| Denomination: | 'Tolga' |
|---|---|
| Previously Proposed Denomination: | 'QFL-R1B' |
| Botanical Name: | Lactuca sativa |
| Applicant/Holder: |
Foundation for Breeding Lettuce and Leafy Vegetables 316, Rang Saint-André Napierville, Quebec J0J 1L0 Canada |
| Breeder: |
Djamila Rekika, Foundation for Breeding Lettuce and Leafy Vegetables, Napierville, Quebec |
| Application Date: | 2024-05-07 |
| Provisional Protection:: | 2024-05-07 |
| Application Number: | 24-11738 |
Variety Description
Variety used for comparison: 'Green Towers'
Summary: At harvest maturity, the leaf of 'Tolga' has an erect attitude whereas that of 'Green Towers' has a semi-erect attitude. The degree of glossiness on the upper side of the leaf of 'Tolga' is weak whereas that of 'Green Towers' is absent or very weak. The upper side of the leaf of 'Tolga' has a medium degree of blistering whereas that of 'Green Towers' has a weak degree of blistering. The plant diameter of 'Tolga' is smaller than that of 'Green Towers'. In cross-section, the head of 'Tolga' has a smaller diameter than that of 'Green Towers'. At flowering, the plant of 'Tolga' is taller than the plant of 'Green Towers'. Harvest maturity for the plants of 'Tolga' occurs mid-season whereas harvest maturity occurs early in the season for the plants of 'Green Towers'. Under long day conditions, bolting begins mid-season for 'Tolga' whereas bolting begins early for 'Green Towers'. The seed coat of 'Tolga' is black whereas it is white for 'Green Towers'.
Description:
PLANT: open head type, absent or weak axillary sprouting, bolting begins mid-season under long day conditions, harvest maturity at mid-season
SEEDLING: no anthocyanin colouration, entire leaf blade at 10 to 12 leaf stage
HEAD: romaine type, open head formation, narrow elliptic shape in longitudinal section
LEAF: medium thickness, erect attitude at harvest maturity, medium elliptic shape, no hue of other colour on green outer leaf, medium to strong intensity of green colouration on outer side of outer leaf, no anthocyanin colouration, weak glossiness on inner side, medium degree of blistering, small sized blisters, absent or very weak degree of undulation of margin, flabellate (fan shaped) venation
INCISIONS OF MARGIN ON APICAL PART OF LEAF: shallow
SEED: black seed coat
Origin & Breeding History: 'Tolga' (experimental designation 'QFL-R1B') originated as a single plant selection using the pedigree method. The initial cross between the F6 line ('Remus' x 'Blonde lente à monter'), as the female parent, and the variety 'Gorilla', as the male parent, was conducted in the greenhouses of Agriculture and Agri-Food Canada Horticultural Research and Development Centre in Saint-Jean-sur-Richelieu, Quebec in the fall of 2008. The variety was advanced from the F1 to the F8 generation at the Sainte-Clotilde experimental station and at a muck soil farm in Napierville, Quebec. One F8 plant was selected in 2019 based on leaf characteristics, plant shape, resistance to premature bolting and absence of tipburn symptoms. Seed evaluation and multiplication were also conducted in San Joaquin Valley, California, USA. Trials were assessed in replicated plots from 2020 to 2023. In December of 2023, the new variety was designated as 'QFL-R1B'.
Tests & Trials: The comparative trials for 'Tolga' were conducted at the Production Horticole Van Winden farm, in Sherrington, Quebec during the summers of 2022 and 2024. Both the candidate and reference varieties were sown in the greenhouse and later transplanted into fields of organic soil. Plots were arranged in a RCB design with 3 replications. Each plot contained 66 plants resulting in a total of 198 plants per variety. The plots were composed of two rows spaced 35.5 cm and planted in mounds that were 10 metres long and 0.91 metres wide. The plants were grown under normal conditions for cultivation with long days (photoperiod between 15 and 16 hours per day). The lettuce was harvested and evaluated at the time of optimal maturity during the second and third week of July. Measured characteristics were based on the measurements of 36 plants per variety except for the plant height at flowering which was based on a total of 20 plant measurements per variety. Mean differences were significant at the 5% probability level based on LSD values.
Comparison tables for 'Tolga' with reference variety 'Green Towers'
Plant diameter at harvest maturity (cm)
| 'Tolga' | 'Green Towers' | |
|---|---|---|
| mean 2022 (LSD=1.21) | 34.1 | 39.9 |
| std. deviation 2022 | 2.25 | 2.89 |
| mean 2024 (LSD=1.18) | 32.7 | 38.3 |
| std. deviation 2024 | 2.89 | 2.10 |
Head diameter in cross-section (cm)
| 'Tolga' | 'Green Towers' | |
|---|---|---|
| mean 2022 (LSD=0.93) | 13.1 | 18.8 |
| std. deviation 2022 | 1.58 | 2.47 |
| mean 2024 (LSD=0.65) | 12.6 | 16.1 |
| std. deviation 2024 | 1.35 | 1.43 |
Plant height at flowering (cm)
| 'Tolga' | 'Green Towers' | |
|---|---|---|
| mean 2022 (LSD=2.11) | 107.5 | 90.2 |
| std. deviation 2022 | 2.47 | 3.95 |
| mean 2024 (LSD=2.63) | 98.7 | 82.7 |
| std. deviation 2024 | 4.60 | 3.56 |
Click on image for larger view
Lettuce: 'Tolga' (left) with reference variety 'Green Towers' (right)
Click on image for larger view
Lettuce: 'Tolga' (right) with reference variety 'Green Towers' (left)
- Date modified: