Chokecherries and pincherries are commonly used in landscaping. Some of the selections such as `Garrington', `Mary Liss' and `Jumping Pound' have large fruits of good quality suitable for food processing. The species are also very well adapted to severe winter conditions of the Prairie Provinces. In our studies, in vitro propagation of the selections was undertaken. The best results with initiation of cultures were observed when dormant buds were used as explants on MS medium with 30 g/L sucrose, 0.1 mg/L NAA and 1.0 mg/L BAP (4 wks, 24/22°C day/night, 16 hrs photoperiod 3000 lux). Optimal proliferation in both species was on MS medium with 1-2 mg/L BAP, 80 mg/L AdSO4 and 170 mg/L NaH2PO4. Rosettes produced were placed on medium without hormones prior to rooting. Rooting was performed ex vitro in root-trainers (soilless mix) on the greenhouse bench under mist. Basal dip in commercial rooting powder Stimroot 1 (0.1% IBA) was equally effective to spray application (2 mg/L IAA with 0.5 mg/L NAA). Average of 77% rooting with `Garrington, 72% and 81% rooting with `Jumping Pound' and `Mary Liss' was observed respectively.
Kris Pruski, Tina Lewis and Mohyuddin Mirza
Agnieszka Masny, Edward Żurawicz, Kris Pruski and Wiesław Mądry
General combining ability (GCA) and specific combining ability (SCA) effects of 10 strawberry (Fragaria ×ananassa) cultivars (Darselect, Selvik, Elianny, Figaro, Sonata, Susy, Salsa, Albion, Charlotte, and Filon) for severity of verticillium wilt (Verticillium dahliae) were estimated. Progeny consisting of 45 F1 full-sib families from the crosses made in a half diallel mating design according to the IV Griffing’s method was evaluated in two field experiments conducted in 2009 and 2010 on a soil heavily infested with V. dahliae inoculum. Each hybrid family was represented by 60 seedlings (four replicates of 15 plants each). The analysis of variance revealed significant (P < 0.01) GCA and SCA effects of the parental cultivars for the verticillium wilt severity in plants. This suggests that genetic additive and non-additive effects are involved in the inheritance of strawberry tolerance to verticillium wilt. In 2009, a significant negative GCA effect (P < 0.05) for the verticillium wilt severity in plants was found in ‘Selvik’, ‘Filon’, and ‘Sonata’, indicating genetic transmission of tolerance from parents to the offspring. On the other hand, a significant (P < 0.05) and positive for the verticillium wilt severity GCA effect was found for ‘Figaro’ in 2009, indicating the transmission from this parent to its offspring relatively high susceptibility to the wilt. Only in one hybrid family, ‘Albion’ × ‘Charlotte’, was the SCA effect significantly positive (P < 0.05) for verticillium wilt severity in plants, whereas two other hybrid families—‘Selvik’ × ‘Salsa’ and ‘Sonata’ × ‘Albion’—showed significantly negative SCA effects (P < 0.05). Three of 10 evaluated genotypes (i.e., ‘Selvik’, ‘Filon’, and ‘Sonata’) were found to be the most valuable parents to the strawberry breeding program for tolerance to verticillium wilt. The least suitable cultivar for this purpose was ‘Figaro’.