Field evaluation of mulberry accessions for susceptibility to foliar diseases in Uasin-Gishu district, Kenya

Abstract

The incidence and severity of foliar disease pathogens in five mulberry accessions (Embu, Thika, Thailand, Kanva-2 and S41) grown in Kenya were evaluated under field conditions in Eldoret. The plants were rated for disease incidence and severity in two mulberry growth cycles over a period of 10 months (May 2009 to February 2010). A high incidence of 58.3% bacterial leaf blight (Xanthomonas campestris pv. mori) disease prevalence was recorded on Embu accession, 36.6% incidence of fungal leaf blight (Alternaria alternata) on Thika and 26.0% for S41 accessions. Black leaf spot (Pseudocercospora mori) disease was high (48.93%) on the Thailand accession, while brown leaf spot (Myrothecium roridum) was recorded with a low (3.61%) incidence on the Kanva-2. Susceptibility of accessions to diseases was highest in Embu, followed by Thailand, Thika and S41 that were moderately susceptible, while Kanva-2 accession was resistant. Our results suggest that Kanva-2 accession can be utilized in future disease resistance breeding programmes to confer disease resistant trait in mulberry varieties.

Key words: Mulberry, Xanthomonas campestris pv. mori, Alternaria alternata, Pseudocercospora mori, Myrothecium roridum.