The used cultivars were mostly obtained from previous crossings with cultivars of various origins, mainly Swedish, Scottish, Polish, and French.
In the present study, cultivars were first selected on their morphologic and agronomic characteristics: the dimension of flowers, ability for self-pollination, tolerance to diseases such as powdery mildew, anthracnose, rust, and tolerance to scales.
Scores reported in Table 2 were established as follows:

Fungal diseases: 0 = no trace to 5 = highly sensitive

White Peach Scale: 0 = no trace to 4 = whole plant infected (on old wood, i.e., more than 2 years old)

Flowering precocity: 1 = flowering in early April to 7 = late flowering in mid-May.

Synchronizing of flowering: 1 = synchronous to 6 = not synchronous (meaning that different stages of flower organs were present at the same time on the plant. For the same plant, it may vary depending on the considered year. Flowering was scored weekly from April to the end of May).

A collection of 316 hybrid plants was obtained from 7 crossings between the variety of Noir de Bourgogne and other cultivars.
The selected blackcurrant cultivars (Table 2) were grown in an open field on an experimental plot located in Burgundy (France, 47°14′6.508″ N 5°6′28.096″ E). Hybrids were grown on the same plot but potted.
For cultivars, all plants were about six years old and were pruned each year in winter around January (only dead and obstructing branches were cut). Each blackcurrant plant got fertilizers (nitrogen, potassium, magnesium, and phosphorus), but neither watering nor chemical weeding. For hybrids, all plants were two years old for harvesting because they did not produce berries the first year. Only hybrids with enough berries to be analyzed were harvested and used for this study (Table 3).
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