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Colletotrichum gloeosporioides, cause of Very few pathogens reported on mile-a-minute (1? rust and 2-4? smut fungi prior to discovery anthracnose of mile-a-minute in Turkey, is a of C. gloeosporioides ) potential biological control agent of this weed in the U.S.

D. K. Berner 1, C. A. Cavin 1, I. Erper 2, and B. Tunali 2

1USDA-ARS-Foreign Disease-Weed Science Research Unit, Ft. Detrick, MD 2Phytopathology Division, Ondokuz Mayis University, Agricultural Faculty, Department of Protection Samsun, Turkey

Mile-a-minute Disease Exploration

• May 15 to May 29, 2010 • Search area based on obscure report of P. perfoliata from the 1980s – In Turkey, the plant is present on the northern face of the Kaçkar range of mountains in north-eastern Turkey (Güner, 1984). – Güner A (1984) A new record for the flora of Turkey and a new sub from Anatolia. Candollea 39 , 345-348 • Search area from Trabzon to Kaçkar mountains near Ardesen, Turkey

Background • Tea-producing area of Turkey beginning in 1950s • Tea plant stocks and seeds imported from China • Mile-a-minute is not native to Turkey • Likely introduction with tea plant stocks/seeds • However, mile-a-minute is not invasive in Turkey • In fact, it is relatively rare • During the initial search period no mile-a-minute were found

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• Diseased plants collected on July 1, 2010 (more than 1 month after first exploration trips) in same area as first exploration • Collected along the Firtina River near Ardesen, Turkey by Dr. Ismail Erper, Plant Pathologist, Agriculture Faculty, Ondokuz Mayis University, Samsun, Turkey • Disease introduced along with mile-a-minute? • C. gloeosporioides not reported on tea

Original diseased material after arrival at FDWSRU quarantine

The pathogen

• gloeosporioides (Penz.) Penz. & Sacc. • Anamorph (asexual) Acervuli with setae • Facultative saprophyte • Pezizomycotina; ; Glomerellales;

Acervuli in leaf tissue • Teleomorph (sexual stage) is [Stoneman] Spauld. & H. Schrenk but not observed with this isolate, or many others • Perhaps the most widely and safely used plant pathogen for Conidia biological control of weeds

Typical salmon-colored colony on V8 juice agar Appressoria

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The pathogen continued Greenhouse inoculations •Many highly specific special forms ( formae speciales, f. sp.) •Most famous is C. . gloeosporioides f. sp. aeschynomene • Conidia from 14-day-old pure cultures •Active ingredient in commercial mycoherbicide Lockdown® • Spray-inoculated, in an aqueous suspension of 1.0 × 10 6 •Control of northern jointvetch (Aeschynomene virginica L.) in rice conidia ml -1 • In commercial use, by one name or another, i.e., Collego, since 1980s • Healthy stems and leaves of nine ca. 30-day-old mile-a-minute • Weeds controlled by other formae speciales include: plants produced from cuttings • Miconia calvescens (Killgore et al. 1999), • Inoculum sprayed on plants until runoff •Malva pusilla and Abutilon theophrasti (Mortensen 1988; Mortensen and Makowski, 1997), • Plants placed in a dew chamber at 25° C for 16 h with no •Clidemia hirta (Trujillo et al. 1986), lighting •Jussiae decurrens (Boyette et al. 1979), • Transferred to a 20-25 °C greenhouse with supplemental •Cuscuta spp. (Cartwright and Templeton 1989) lighting by 400 w sodium vapor lights for 14 h day length •Salsola tragus (Berner, et al., 2009) • Lesions developed on all inoculated plants after 7 days •Dispersal in nature is, like other C. gloeosporioides, likely by rain • C. gloeosporioides re-isolated from all inoculated plants splash of conidia

The disease Species of in FDWSRU seed collection for initial host-range tests

Aconogonon divaricatum Bistorta bistortoides Brunnichia ovate Eriogonum umbellatum Fagopyrum esculentum Fagopyrum tataricum Fallopia convolvulus Fallopia japonica Oxytheca perfoliata Persicaria maculosa Persicaria sagittata Polygonum arenastrum Polygonum aviculare rhabarbarum Rheum x hybridum Rumex acetosella Rumex crispus Rumex venosus

Flowers

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