The European Union Common Catalogue (EUCC) for potato contains over 1000 varieties. Each year member states add varieties to the list after they have undergone Distinctness, Uniformity and Stability (DUS) testing according to international guidelines. A rapid and robust method for variety identification to aid the management and maintenance of existing variety collections and for the screening of new candidate varieties would therefore be a highly useful tool for DUS testing stations. A database containing key morphological characteristics and microsatellite data was constructed for varieties on the 2006 list of the EUCC for potato. Rules for scoring SSR markers in different laboratories were established to allow a harmonized scoring of markers. Almost all varieties (99.5%) were shown to have unique molecular profiles and in pair wise comparisons 99.99% of all variety pairs could be distinguished. This clearly shows the versatility of the markers and database for identifying potato samples.

Due to the yearly increase in the numbers of new potato varieties obtaining Plant Breeders' Rights the reliable maintenance of large culture collections of reference varieties for DUS testing is becoming more and more difficult, as accidental mix ups might occur. Efficient identification methods and databases can act as an aid to overcome this problem. Identification of cultivars by morphological characteristics is a highly skilled and time-consuming task, and for these reasons a rapid and robust method for variety differentiation has become extremely desirable. By use of a set of nine microsatellite (SSR) markers we can differentiate over 1,000 cultivars, including the majority of varieties on the European Union Common Catalogue, but excluding somaclonal variants (e.g. Red King Edward and King Edward) and mutants. The whole identification process from DNA extraction to accurate identification can be carried out in a single day.

Su in mar)Conidia of two isolates of Elsinor venefa were consistently produced in vitro by a 3-stage culture system in which spai-sely sporulating microcolonies produced on corn meal agar were used to 'seed' C'mpek-Dox V 8 juice agar. E. veneta then spoi-ulated on this medium i f discs wet-e floated mycelium uppermost on sterile distilled \later f'or 24 ti at 25°C. Both isolates also produced microconidia in vifro.Only the growing apices of raspberry canes were susceptible to infection. Of 12 genotypes inoculated in the glasshouse, a red raspberry derivative of Rirbirs coi.eu~/r5, Ehl RS 2769/9, was the most resistant and the black raspberry selection SCRl 815286 and cv. Malling Delight were the most susceptible. Of four red ra5pbert-y cultivars inoculated in the field cc'. Malling Orion was the most susceptible. Inoculated flowers and debeloping fruits produced malformed fruits bccnuse int'ccled drupelcts were sniallcr o r slower to ripen than uninfected ones. 111 trod tic t ion Elsinoe \eneta (Burkh.) Jenkins (conidial state: Sphaceloiiia necator (Ell. & Ev.) Jenkins & Shear) causes cane spot or anthracnose on the canes and leaves of cultivars of the genus R~i D u 5 , most notably cultivars of black I-aspberrv ( R . occidentulis L.), red raspberry ( R . idueus

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To develop efficient breeding strategies for the improvement of oil content and onset of flowering in Dimorphotheca pluvialis, narrow‐sense heritabilities of these characters were estimated. Forty plant progenies were tested in 2 years and heritabilities were estimated from parent‐offspring regression as well as from half‐sib family variance components analyses. For oil content, the heritabilities estimated by means of parent‐offspring regression were 0.36 and 0.33 for 1993 and 1994, respectively. The heritabilities obtained from the variance components analyses were 0.41 and 0.23 for the two years. Heritability estimates for onset of flowering showed more variation. From parent‐offspring regression, the heritabilities were 0.72 and 0.37, and from variance component analysis the estimates were 0.53 and 0.19 for 1993 and 1994, respectively. The obtained heritability values and realized responses suggest that particularly in early selection generations, even with mass selection, considerable progress can be expected. Since correlation studies revealed neither phenotypic nor genotypic correlation between oil content and onset of flowering, selection for both characters can be undertaken independently.