K. Y. Rashid

CDC Bethune flax

CDC Bethune, is a medium-late-maturing oilseed flax (Linum usitatissimum L.) developed by Crop Development Centre, University of Saskatchewan, Saskatoon, Saskatchewan. This cultivar has medium oil content, medium oil quality, medium seed size, good lodging resistance and high yield when seeded early in the Black and the Brown Soil zones of the prairies. It is immune to North American races of rust caused by Melampsora lini and moderately resistant to wilt caused by Fusarium oxysporum f. sp. lini. Key words: Flax, oilseed, Linum usitatissimum L., cultivar description

The role of volatile and non-volatile antibiotics produced by Pseudomonas chlororaphis strain PA23 in its root colonization and control of Sclerotinia sclerotiorum

Abstract Pseudomonas chlororaphis strain PA23 has demonstrated excellent biocontrol in the canola phyllosphere. This bacterium produces the non-volatile antibiotics phenazine and pyrrolnitrin as well as the volatile antibiotics nonanal, benzothiazole and 2-ethyl-1-hexanol. In vitro experiments were conducted to study the effects of different mutations on the production of these three organic volatile antibiotics by PA23. In planta experiments in the greenhouse investigated the role of the non-volatile antibiotics on root colonization and biocontrol ability of PA23 against Sclerotinia sclerotiorum on sunflower. Analysis of phenazine- and pyrrolnitrin-deficient Tn mutants of PA23 revealed no differences in production of the three volatile antibiotics. On all sampling dates, PA23 applied alone or in combination with the mutants showed significantly higher (P = 0.05) root bacterial number and Sclerotinia wilt suppression (P = 0.05). Decline of the bacterial population seemed to be inversely proportional to/or negatively correlated with the number of antibiotics produced by PA23 but the relative importance of phenazine or pyrrolnitrin on root colonization and/or wilt suppression was not clear. In several cases, the strains producing at least one antibiotic maintained relatively higher bacterial numbers than non-producing strains. However, by 6 weeks after sowing, there was a rapid and significant (P = 0.05) increase in the proportion of introduced bacteria capable of producing at least one antibiotic over the total bacterial population. Furthermore, combining certain mutants with PA23 reduced the root colonization and biocontrol ability of PA23. Strain PA23-314 (gacS mutant) showed competitive colonization in comparison to the other mutants for most sampling dates.

2149 solin (low linolenic flax)

2149 solin (Linum usitatissimum L.) was developed by Agricore United and combines very high oil content with high yield. In all soil zones of western Canada, the yield of 2149 was similar to the check cultivar, 1084. The 1000 seed weight, oil content and meal protein content of 2149 are significantly higher than 1084. 2149 has higher levels of linoleic fatty acid and lower levels of saturated fatty acids. It is immune to North American races of rust [Melampsora lini (Ehrenb.) Desmaz.], is moderately resistant to Fusarium wilt [Fusarium oxysporum Schlecht. F. sp. Lini (Bolley) snyder & Hansen] and is moderately resistant to powdery mildew (Oidium lini Skoric). 2149 is a yellow seedcoat, solin cultivar. Key words: Flax, low linolenic acid, cultivar description, solin

Linola™ 2047 low linolenic flax

Linola™ 2047 was developed by Agricore United. Linola 2047 has significantly higher oil content, meal protein content and linoleic acid content than all previously registered Canadian solin varieties. In the Longer Growing Season of Black Soil zones of western Canada, the yield of 2047 is similar to the other solin varieties. In the Brown and Dark Brown Soil zones, 2047 is significantly lower yielding than previous solin varieties. It is immune to North American races of rust and is moderately resistant to Fusarium wilt. The 2047 Linola is a yellow seeded cultivar like 1084, 989 and 947 solin cultivars. Key words: Fax, low linolenic acid, cultivar description, solin

Verticillium dahliae's VdNEP acts both as a plant defence elicitor and a pathogenicity factor in the interaction with Helianthus annuus

Abstract The soil-borne fungus Verticillium dahliae Kleb. causes a serious wilt disease in many economic crops worldwide, including sunflower. We investigated the role of V. dahliaes necrosis and ethylene-inducing proteins (VdNEP) in the interaction with sunflower. We inoculated two highly and two weakly aggressive V. dahliae isolates onto moderately resistant and susceptible sunflower hybrids. We also synthesized VdNEP protein in vitro and infiltrated it into sunflower control plants to compare its effects with those of the fungus. VdNEP induced wilting symptoms, i.e. chlorosis, necrosis and vascular discoloration but also triggered host defence responses, i.e. hypersensitive response in Nicotiana benthamiana leaves and sunflower cotyledons. It activated the production of reactive oxygen species and the accumulation of fluorescent compounds in sunflower leaves, as well as pathogenesis-related genes (Ha-PR-3 and Ha-PR-5), two defensin genes (Ha-PDF and Ha-CUA1) and those encoding Ha-ACO, Ha-CHOX, Ha-GST and Ha-SCO. The latter suggested that more than one signalling pathway may be involved in the V. dahliae-sunflower interaction. Two other genes (Ha-PAL and Ha-NML1), related to the salicylic acid pathway, were slightly downregulated by VdNEP, suggesting a possible involvement of VdNEP in affecting sunflower defences. The phenotypic changes induced by VdNEP indicate that this protein acts both as a defence elicitor and a pathogenicity factor.

Pathogenic variation of Verticillium dahliae after serial passages through potato and sunflower

Verticillium wilt is a limiting factor in many field crops, including potato and sunflower. The causal agent, Verticillium dahliae Kleb., is known for its high level of diversity and pathogenic variability. In an earlier study, we showed such a high variability among isolates recovered from either potato or sunflower when inoculated on their original or alternative hosts. Verticillium dahliae isolates from potato were more aggressive on both potato and sunflower while the ones from sunflower were to a certain extent more adapted to sunflower than to potato. In the present study, we show the ability of weakly aggressive potato isolates to gain pathogenicity on either potato or sunflower when inoculated to a susceptible potato cultivar ‘Kennebec’ for four successive generations. However, some isolates showed a loss in pathogenicity after four successive passages on susceptible potato cultivar ‘Kennebec’, especially on the moderately resistant potato cultivar ‘Ranger Russet’. Results in terms of gain or loss of pathogenicity by potato and sunflower isolates are discussed in relation to the effect of successive passages through their original or alternative hosts. Key words: Verticillium dahliae Kleb., potato, sunflower, host of origin, alternative host, successive passages, pathogenicity gain/loss, pathogenicity index. La verticilliose constitue un facteur limitant pour de nombreuses cultures incluant la pomme de terre et le tournesol. L’agent causal, Verticillium dahliae Kleb., est connu pour son degré élevé de diversité génétique et de variabilité de pouvoir pathogène. Dans une étude précédente, nous avions montré la présence d’une telle variabilité entre des souches isolées soit de pomme de terre soit de tournesol, et inoculées sur leur hôte d’origine ou alternatif. Les isolats de V. dahliae provenant de pomme de terre étaient plus agressifs aussi bien sur pomme de terre que sur tournesol, tandis que ceux provenant de tournesol étaient relativement mieux adaptés sur tournesol que sur pomme de terre. Dans la présente étude, nous montrons la capacité de certains isolats peu agressifs, provenant de pomme de terre, d’acquérir un plus grand pouvoir pathogène, aussi bien sur pomme de terre que sur tournesol, après avoir été propagés pendant quatre générations sur le cultivar sensible de pomme de terre ‘Kennebec’. Par contre, après quatre passages successifs sur le cultivar ‘Kennebec’, certains isolats ont vu leur pouvoir pathogène diminuer, plus particulièrement sur le cultivar partiellement résistant ‘Ranger Russet’. Ces résultats sont discutés en termes de gain ou de perte de pouvoir pathogène, par des isolats provenant de pomme de terre ou de tournesol, dans le but d’élucider l’effet de leur passages successifs sur leurs hôtes d’origine ou alternatif. Mots-clés : Verticillium dahliae Kleb., pomme de terre, tournesol, hôte d’origine, hôte alternatif, passages successifs, gain/perte de pouvoir pathogène, index de pathogenicité.

2090 low linolenic acid flax

2090 was developed by Agricore United. 2090 combines very high oil content with high yield. In the longer growing season Black soil zones of western Canada, the yield of 2090 is similar to 2047 and higher than 1084. In the shorter growing season Black and Grey-wooded soil zones, 2090 is similar yielding to 2047 and 1084. In the Brown and Dark Brown soil zones, the yield of 2090 is higher than 2047 and 1084. It is immune to North American races of rust, is moderately resistant to Fusarium wilt and is moderately resistant to powdery mildew. 2090, 2047 and 1084 are low linolenic acid, yellow seed coat solin cultivars. Key words: Flax, low linolenic acid, cultivar description, solin

The identification of a cleaved amplified polymorphic sequence (CAPS) marker for the flax rust resistance gene M3

A cleaved amplified polymorphic sequence (CAPS) marker has been developed for the flax rust resistance gene M3. This molecular marker was identified in a rust differential for M3 by screening primer sets, whose sequences were based on the nucleotide sequence of the M gene. One primer set was identified that co-amplified, along with other related sequences, a 2.9-kb DNA segment of M3 or an M-like gene tightly linked to the M3 locus. Restriction fragment analysis revealed several unique DNA fragments that were linked to the presence of the M3 gene in a F2 segregating population. This molecular marker along with recently developed markers for the L2, L6, L9, and L11 alleles will be useful for marker-assisted selection in breeding programs for obtaining multigenic resistance against flax rust in Canadian flax cultivars.

AC Watson flax

AC Watson, a medium–early maturing oilseed flax (Linum usitatissimum L.) was released in 1997 by Agriculture and Agri-Food Canada, Research Centre, Morden, Manitoba. The cultivar has high oil quality, medium-large seed size, good lodging resistance, and with good yielding in both early and late seeding in the Black and the Brown Soil zones of the prairies. It is immune to North American races of rust caused by Melampsora lini and moderately resistant to wilt caused by Fusarium oxysporum f. sp. lini. Key words: Flax, oilseed, Linum usitatissimum L., cultivar description

CDC Normandy flax

CDC Normandy, a tissue-culture-derived oilseed flax (Linum usitatissimum L.) was released in 1995 by the Crop Development Centre, University of Saskatchewan, Saskatoon, Saskatchewan. This cultivar is a medium-early maturing, with medium oil content, good oil quality, brown seeds and medium seed size, fair lodging resistance and high yields when seeded early in the Black and the Brown Soil zones of the prairies. It is immune to North American races of rust caused by Melampsora lini and moderately resistant to wilt caused by Fusarium oxysporum f. sp. lini. Key words: Flax, oilseed, Linum usitatissimum L., cultivar description, somaclonal variation