First report of Fusarium oxysporum f. sp. radicis‐cucumerinum on cucumbers in Turkey

Abstract

During a study of Sclerotinia sclerotiorum populations on Ranunculus acris (meadow buttercup) in the UK, dead and dying flowers collected from plants in a Herefordshire meadow were incubated at 20°C in damp conditions. Fungal growth typical of S. sclerotiorum (white fluffy mycelium ⁄ sclerotia) emerging from individual flowers was transferred to potato dextrose agar. DNA was extracted from cultures and the ITS regions of the rDNA amplified and sequenced. BLAST analysis showed that of 32 isolates selected at random, only 17 were S. sclerotiorum while 15 were identified as S. subarctica nom. prov. (= Sclerotinia species 1; HolstJensen et al., 1998;Winton et al., 2006Winton et al., , 2007. All 15 S. subarctica ITS sequences were identical (GenBank Accession No. GU018183). The identity of the S. subarctica isolates was further confirmed by the lack of an intron in the LSU rDNA compared with S. sclerotiorum (Holst-Jensen et al., 1998).A formal description and host range for S. subarctica has yet to be published but it is reported to be morphologically indistinguishable from S. sclerotiorum (Holst-Jensen et al., 1998). However, the cultures of S. subarctica in this study produced fewer but larger sclerotia in vitro (ca. 5AE8 ± 1AE0 mm diameter) than S. sclerotiorum (ca. 4AE1 ± 0AE9 mm). Sclerotinia subarctica has only been reported on wild hosts in Norway (Holst-Jensen et al., 1998) and causing white mould disease on vegetable crops in Alaska (as does S. sclerotiorum; Winton et al., 2006). As oilseed rape is the major crop host of S. sclerotiorum in the UK, its susceptibility to S. subarctica was tested by inoculation of plants and detached leaves. Stem and leaf lesions were identical to those caused by S. sclerotiorum although stem lesions of S. subarctica were slower to develop. This is the first time that infection of oilseed rape by S. subarctica has been demonstrated. The presence of S. subarctica in the UK indicates that this pathogen is not confined to the 'High North' as suggested previously (Winton et al., 2007). Significantly, as S. subarctica causes symptoms very similar to S. sclerotiorum, it may currently be undetected in white mould affected crops in the UK and hence further work to establish its distribution on crops and wild hosts is merited. The presence of S. subarctica (and S. sclerotiorum) on R. acris also suggests that this wild host is a reservoir of inoculum for crop plants.

How Bone Tissue and Cells Experience Elevated Temperatures During Orthopaedic Cutting: An Experimental and Computational Investigation

“…The cortical bone shell is the first medium to be cut through during orthopaedic procedures to expose underlying organs and joints. The bone mineral density of cortical bone is higher than that of porous (75-95%) trabecular bone and experiences higher temperature elevations, with the same drilling/cutting parameters [28]. The duration of cutting/drilling largely depends on the thickness of the cortical bone and, thus, studies in cortical bone are necessary to understand the temperature elevations in bone.…”

Alarming occurrence of Fusarium wilt disease in pea (Pisum sativum L.) cultivations of Jabalpur district in Central India revealed by an array of pathogenicity tests

“…basilici on Ocimum minimum in Portugal. Karaca and Kahveci (2010), published first report of Fusarium oxysporum f. sp. radiciscucumerinum on cucumbers in Turkey.…”

The evaluation of resistance of Luffa cylindrica genotypes to the fungus Verticillium dahliae

“…The concentration of harvested spores was adjusted to 1×10 6 spores/ml. Inoculation was done by the root dipping of seedlings (at 2-4 leaf stage) in spore suspension for 5 minutes (Karaca and Kahveci, 2010). Then, the inoculated seedlings cultivated in plastic pots containing a mixture of soil and sterile peat moss, and incubated in a growth chamber at 25°C with a 12-hour photoperiod.…”