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The activity of metalaxyl, fosetyl-Al, dimethomorph, and cymoxanil against Phytophthora crown rot of peach trees was examined. Application of fosetyl-Al or metalaxyl by painting the trunk (150 g/l) of 3-year-old PR204 trees was inhibitory to growth of the fungus but neither dimethomorph nor cymoxanil were eective. Application of metalaxyl as a soil drench suppressed canker development when the treated trees were subsequently inoculated with Phytophthora cactorum. Fosetyl-Al signi®cantly reduced the growth of fungus compared with cymoxanil, dimethomorph and control but it was not as eective as metalaxyl. Again, dimethomorph and cymoxanil did not in¯uence canker development. Both metalaxyl and fosetyl-Al were active for at least 21 days after applications. Strips of trunk bark were removed from trees, that had been drenched with the tested chemicals 20 days before, and inoculated on the cambium side with P. cactorum. Metalaxyl was the most eective fungicide and fosetyl-Al signi®cantly reduced the development of fungus compared with dimethomorph, cymoxanil and the untreated strips. Colonization of strips treated with dimethomorph was signi®cantly less than untreated strips. In contrast, cymoxanil did not inhibit the growth of fungus. Application of metalaxyl or fosetyl-Al as trunk paint or a soil drench appear to be eective procedures for preventing Phytophthora rot of peach trees.

SPIROU Co., 5 Marconi Str., 142 22 Athens (Greece)Seedlings of tomato (19) and cucurbits (33), previously selected as rootstocks for commercial cultivars, were evaluated for their resistance to verticillium wilt under glasshouse conditions. Disease scoring was based on foliar symptoms, but in plants with no visual or ambiguous symptoms the presence of the pathogen was confirmed by isolations or PCR using specific DNA primers. Five of the cucurbit rootstocks showed resistance to infection, 11 were moderately infected, 11 were susceptible, while the remaining six were very susceptible. In general, Cucurbita pep0 (courgette, pumpkin) and Lagenaria siceraria tolerated infection, Cucumis melo rootstocks were susceptible and Citrullus vulgaris was the most susceptible. When inoculated with race 1 of the pathogen, one of the tomato rootstocks was very resistant, three moderately resistant, nine tolerant, ten susceptible and one very susceptible. Pathogenicity tests with race 2 showed that none of the rootstocks exhibited high tolerance, but that there was some variation in susceptibility. Research is under way to evaluate the reaction of commercial cultivars to verticilliurn wilt when grafted onto resistant rootstocks.

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During the last three years, a new disease was observed in northwestern Greece on Minneola trees, hybrid of mandarin and grapefruit. On May small brown necrotic leaf spots surrounded by yellow halo areas of various sizes appeared and covered a major portion of the leaves with extension of necrosis into the veins. On young fruits small, slightly depressed black spots were the first symptoms, which later became 2-7 mm in diameter. Brown spots were observed on the leaves and fruits in several orchards in the same area, causing leaves and fruits to drop. In some orchards over 50% of the fruits were affected. From the fruit and leaf spots the typical small-spore species Alternaria alternata was isolated. Pathogenicity tests were performed by artificially inoculating fruits of Minneola, common mandarin and Clementine. The symptoms of the disease were reproduced only on fruits of Minneola hybrids by the specific strain of the fungus Alternaria alternata pv. citri. Different citrus susceptibility tests indicated that mandarins Minneola, Nova and Page were very susceptible to tested isolates while Clementine SRA and Poros Clementine were not. All lemons and lime Seedless were not susceptible. Grapefruit New Hall was not susceptible, while the Star Ruby was. Orange Lane Late, Navel Late, Oval Poros, Olinda, Navel Athos were not susceptible and only Moro showed reaction being slightly susceptible only to one isolate.

Specimens of diseased asparagus (108) were selected from 17 fields in northern Greece. The asparagus crowns showed limited or widespread brown discoloration or extensive internal rot with fibrous tissues. A red‐brown discoloration was also observed on the roots and, in a serious infection, most of the roots were totally destroyed and only their epidermis and ribbon‐like central axis remained. 68 strains of Fusarium proliferatum, 25 of F. oxysporum, 19 of F. solani, and 1 strain of Rhizoctonia solani were isolated from crowns and roots. Single‐spore isolates were subcultured from 50 strains of F. proliferatum, 21 of F. oxysporum and 7 of F. solani. These isolates were evaluated for pathogenicity by inoculating cultivar UC157F1 of asparagus in an in vitro agar test‐tube assay for 21 days at 29–32°C, with a light period of 16 h. Isolates of F. proliferatum and F. oxysporum were found to be the most pathogenic. The pathogenic F. oxysporum isolates were characterized as f.sp. asparagi.

Races and vegetative compatibility groups (VCGs) inGreek isolates of Fusarium oxysporum f. sp. melonis (Fom) were characterized. Three races (0, 2 and 1-2) among 12 isolates tested and two VCGs among 19 isolates tested, were identified. Race 1-2 was the most common and race 1 was not detected. One widespread VCG corresponded to a VCG previously reported from Israel (coded 0138), and included seven isolates of races 0 and 1-2. The other VCG, which was unclassified, included four isolates of races 0, 2 and 1-2. The latter VCG was detected only in a specific melon-growing location of Evros. The remaining eight isolates tested for VCG did not show positive reactions with other isolates, with each other or with the testers of VCGs 0135 or 0138, although they produced complementary mutants. Using two inoculation methods, the local cv. ÔGolden HeadÕ was found susceptible to all known Fom races, and especially to race 1-2. These results show the presence of more than one VCG and the widespread distribution of the race 1-2, in Greece.www.blackwell-synergy.com

A severe disease of cumin causing pre-mature plant death was observed in the island of Chios, Greece. Disease symptoms included sudden red-brown shrivelhng of the fohage, growth retardation and pre-harvest plant death. From plants showing early disease symptoms Fusarium oxysporum (F.o.) was consistently isolated. In artificial inoculations, representative isolates from this fungus species were found to be pathogenic on cumin, confinning the belonging to the f. sp. cumini. This is the first report of F.o. f.sp. cumini in Greece. ZusammenfassungDas Vorfcommen von Fusarium oxysporum f. sp. cumini auf der Insel Chios, Griechenland Auf der Insel Chios wurde ein starker Befall des Kretizktimmels beobachtet, welcher zum fruhzeitigen Absterben der Pflanzen fuhrte. Die Krankheitssymptome umfaBten das plotziiche rot-braune Ausdorren der Blatter, eine Wachstumsretardation sowie das frilhzeitige Absterben der Pflanzen. Aus Pflanzen mit fruhen Befallssyptomen konnte Fusarium oxysporum (F.o.) stetig isoliert werden. Nach kilnstlichen Inokulationen mit reprasetitativen Isolaten dieses Pilzes konnte nachgewiesen werden, daB diese Art pathogen an Kreuzktimmel ist und von daher f.sp. cumini. Uber das Vorkommen von F.o. f.sp. cumini in Griechenland wird zum ersten Mal berichtet. IntroductionBy the end of 1970s, cumin (Cuminum cyminum L.) was the main crop, growing in rotation with anise (Pimpinella anisum L.) during the spring period (March to June) in the island of Chios. The cultivated area occupied about 150-200 ha of arid sloping, small fields in the south-east provinces of the island. However, from the early 1980s, cumin crop has been restricted year by year, such that.