First Report of Diplodia Cane Dieback of Grapevine in Bolivia

Grape (Vitis vinifera L.) is an important commercial crop in the temperate regions of Bolivia where it has been grown for hundreds of years. In October of 2001, diseased canes of grape (cv. Muscat of Alexandria) were collected in a vineyard in Yotala, Department of Chuquisaca in southern Bolivia. In this planting of more than 1,000 plants, more than 75% were exhibiting cane dieback symptoms and many were dead or dying. No disease was observed on grape berries. Symptoms of the disease were similar to those reported for Diplodia cane dieback (1). Cankers ranging from 2 to 10 cm long and 0.5 to 3 cm wide were observed. When diseased canes were placed in a moist chamber, conidia oozed from pycnidia in black cirri. Immature conidia were hyaline and one-celled, but mature conidia were dark brown (20 to 30 × 10 to 15 μm) with one median septum and longitudinal striations. The pathogen was tentatively identified as Lasiodiplodia theobromae (Pat.) Griffon & Maubl. (synonyms Diplodia natalensis Pole-Evans and Botry...