Sorghum Diseases in India

Table 1. Foliar pathogens of sorghum caused by fungi. 1
Primary Non-
Common name survival Initial Inoculum sorghum
Causal agent of the disease mechanisms inoculum dispersal hosts
Leaf blade diseases
Exserohilum turcicum Leaf blight M+C in S+R,
WH
C Y/HS
Bipolaris sorghicok Target leaf spot M+C in R,WH C N
Cercospora sorghi Gray leaf spot MinR,WH C Wind N
Cercospora
fusimaculans
Ladder spot M in R, WH? C N
Puccink purpurea Rust WH Urediospores N
Gloeocercospora
sorghi
Zonate leaf spot SC in S+R
c
Y
Ramulispora sorghi Sooty stripe SC in S+R C from SC N
Ramulispora Oval leaf spot SC in S+R C from SC Rain N
sorghicola and
Colletotrichum
graminicola
Leaf anthracnose MinR,WH,SB C from SC wind Y/HS
Ascochyta sorghina Rough leaf spot M+C? in R, WH C from
pycnidia
N
Phylkchora sacchari Tar spot WH Ascopores N
Leaf sheath diseases
Gloeocercospora sorghi Zonate leaf spot SC in S+R C from SC Soil and Y
Sclerotium rolfsii Southern
sclerotial
rot
SC in S+R M soil Y
Rhizoctonia spp Banded leaf and
sheath blight
SC+M in S+R M Splash Y
1. C = conidia, HS = host specific, M = mycelia, N = no, R = host residue, S = soil, Sb = seedborne, SC = sclerotia,
WH = weed host, Y = yes.
may lead to underestimation of disease incidence;
conversely, lesions on red and purple genotypes
are in greater contrast, and could lead to
overestimates. Some foliar diseases (target leaf
spot and gray leaf spot) have symptoms or
symptom progression similar to those produced
by other pathogens or other biotic and abiotic
factors.
Most foliar pathogens of sorghum primarily
attack the leaf blade but under epidemic and
extended disease-conducive environments they
may also attack leaf sheaths. Puccink purpurea
Cooke also attacks peduncles and Colletotrichum
graminicok (Ces.) G.W. Wilson also attacks stems
and seed. There are a few pathogens that pri­
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marily attack only the leaf sheath (Sclerotium
rolfsii Sacc.) and secondarily attack the leaf blade
(Rhizoctonk spp). Gloeocercospora sorghi D. Bain
and Edg. has historically been observed principally
on leaf blades but it may be more common
on leaf sheaths where it goes unnoticed on basal
leaf sheaths or is mistaken for charcoal rot (Odvody
and Madden 1984).
New Diseases
The only new disease described since 1978 that
is recurrent and has extensive geographic distribution
is ladder leaf spot caused by Cercospora