Susceptibility of sixteen sugarcane varieties to infection with pokkah boeng
disease and effect of the disease on vegetative growth of sugarcane plants were
tested under open greenhouse conditions and artificial inoculation of Fusarium
subglutinans in 2010/2011 and 2011/2012 seasons in Upper Egypt. All tested
sugarcane varieties were susceptible to infection with the pathogen with different
degrees of susceptibility. In the two tested seasons, the G.T.54-9 and G.2004-32
varieties showed high susceptibility followed by G.2003-47, G.2003-3, G.1999-
103 and G.1998-28, then other tested varieties. However, G.2001-79 and
G.2000-176 varieties proved to be moderately susceptible. K2 isolate of F. subglutinans
caused higher disease severity than K5 isolate, on the tested sugarcane
varieties in both tested seasons. The interaction between tested varieties and fungal
isolates was significant in both seasons. The highest disease severity (٧٢.0
and 76.0%) was recorded on G.T.54-9 and G.2004-32 varieties inoculated with
K2 of F. subglutinans in both seasons, while the lowest disease severity (20.0%)
was recorded on G.2001-79 and G.2000-176 varieties infected with K2 and K5
isolates. Infection with of F. subglutinans isolates increased the number of tillers/
plant by two folds in infected plants compared with non-inoculated plants in
both seasons, however, the number of internodes/plant, stalk length and stalk diameter
of the tested sugarcane varieties were significantly decreased by infection.
Keywords: Sugarcane plants, pokkah boeng disease, Fusarium subglutinans,
sugarcane varieties, vegetative growth.