Ascochyta sorghi is a fungal plant pathogen. It causes Ascochyta leaf spot on barley that can also be caused by the related fungi Ascochyta hordei, Ascochyta graminea and Ascochyta tritici. It is considered a minor disease of barley.
Hosts and symptoms
Ascochyta sorghi infects grain crops such as sorghum (Sorghum bicolor), Johnson grass (Sorghum halepense), Sudan grass (Sorghum sudanense), and barley (Hordeum vulgare). It can also infect wild sorghum species. Symptoms of rough leaf spot can appear on leaf blades, leaf sheaths, peduncles, stalks, and glumes of susceptible species. Rough leaf spot can eventually lead to leaf senescence. ==Management==
Management
Ascochyta sorghi is controlled through host plant resistance, cultural practices, and chemical application when necessary. Varieties of sorghum are not generally susceptible to rough leaf spot, although exceptions do exist. Other sanitation, such as using clean seed and removing alternate hosts, such as wild sorghum species, can reduce disease incidence. Spores are spread from water splash, and can also be transmitted through contact with field equipment, especially when leaves are wet, so delaying field operations until plants are dry can help prevent spread of the pathogen. If necessary, the application of fungicides can help limit disease severity. ==Importance==
Importance
Ascochyta sorghi is found in all sorghum growing areas. The lack of economic importance of rough leaf spot is thought to be due to the prevalence of resistant varieties. Weimer et al. (1937) reported that A. sorghi had the capacity to become damaging in Georgia. Historically, rough spot has been responsible for crop losses between 3 and 10% in French Equatorial Africa. ==See also==