Phragmidium violaceum newly reported to infect wild blackberries in Turkey

Turkey, situated between Asia and Europe, is a very important area for plant diversity.The rich biological diversity of Turkey, in particular for wild edible fruits including blackberries, is a result of the extreme variations in climate within a very small area and varying altitudes of the valleys, in which differences in elevation can reach up to 3,000 meters (Ercisli, 2004). Recently, wild blackberries have been growing as border plants around fruit orchards in Hatay province of Turkey. Blackberry cultivation started in the Marmara region several decades ago and has now been introduced as a new crop in Hatay and Adana provinces of the Mediterranean and Black Sea regions (Kafkas et al., 2006). Consumption of fresh and frozen blackberries has increased in the past few years in Turkey.In search for alternative crops for farmers, blackberries have great potential as a crop of high market value.

In late October 2008, rust-like symptoms were observed on approximately 25% of wild blackberry plants (Rubus fructicosus) in Belen, Samandag and Reyhanlı districts of Hatay. Foliar symptoms included circular purplish leaf spots 1.5-2 mm in diameter with yellow to tan centres on the upper leaf surface (Fig. 1) accompanied by cream to yellowish-orange uredinia on the lower surface (Fig. 2). Urediniospores were globose or ellipsoid, 20-30 μm in diameter with 2.5 μm thick walls. Cylindrical teliospores were dark brown and three- to five-celled. Three-celled teliospores excluding the papilla were 50-60 μm long by 25 to 30 μm wide, four-celled teliospores were 70-75 μm long by 30 μm wide. Based on morphological characteristics, the rust fungus was identified as Phragmidium violaceum (Schultz) G. Winter (Laundon & Rainbow, 1969). Blackberry rust was reported in Australia, Chile, Europe, Iran, Iraq, New Zealand, South Africa and USA on several species of Rubus (Farr et al., 2009). To our knowledge, this is the first report of rust caused by P. violaceum on wild blackberries in Turkey. The presence of the disease in wild blackberries has significant risk for cultivated blackberries in commercial orchards.