Ustilagomycotina

Detailed description about subphylum ustilaginomycotina has been explained in easy manner

1. USTILAGOMYCOTINA
N.H. SHANKAR REDDY
2
nd
Ph.D. Plant Pathology
Annamalai University

3. Ustilaginales> Smuts
Symptoms–Entire grain are replaced or converted into black
color powdery masses

4. Economically important pathogens include
Ustilagomaydis (corn smut)
Tilletiacontroversa(dwarf bunt of wheat)
Tillietatriticiand T. laevis(common bunt)
Tilletiaindica (Karnal bunt of wheat)
Urocystisagropyri(flag smut)

5. Corn smut -Ustilagomaydis
•Formation on galls on ears, leaves, stalk or
tassels

6. Flag smut of wheat –Urocystisagropyri
Deformed tillers, infected plants gets twisted and later converted into black to brown colour
powdery masses

7. Difference between various smut diseases of sorghum
Particulars Grain smut Head smut Loose smut Long smut
Pathogen Sphacelothecasorghi Sphacelothecareliana SphacelothecacruentaTolyposporiumehrenbergii
Symptoms Individualgrains are
replacedbysmutsori,
mostlyoftheeargotinfected
The entireearhead/
inflorescenceiscompletely
convertedintosmutspores
Majorityoftheearportion
gotaffected
Smallportionoftheflorets/
grainsareinfected
Sori Small Small Medium-Long VeryLarge
Columella Present(short) Absent Present(longblackpointed
columella)
Absent
Siteofinfection Ovary Inflorescence Ovary Ovary
Diseasessurvival Externallyseedborne Soilandseedborne Externallyseedborne Airborne
Sporeviability >10years 2years 4years 2years
Management Allthesesmutscanbemanagedbyseedtreatmentwithvitavax@2gm/kgofseed

8. Write difference
between Rustand
Smut
Particulars Rust Smut
Description Rustyappearanceonstemsand
leaves
Entiregrainsareconvertedinto
blackcolourpowderymass
Parasitism Obligateplantparasite Facultativesaprophyte
Class Uredinales Ustilaginales
Perfectspore Terminal Intercalary
Number of
basidiosporesper
mycelium
Four Many
Clampconnection
and secondary
mycelium
Rare Common
Heteroecism Common Absent
Polymorphism Distinct Absent
Nature Wheatrustsareheteroecious
andotherrustsareautoecious
Allsmutsareautoecious
Hosts Twohostsinlifecycle Onlyonehostinlifecycle
NumberofsporesRustproduceall5stagesof
spores
pycniospores, aeciospores,
urediospore,teliosporeand
basidiospores
All5stagesofsporesareabsent