‘Karnal bunt’ is a disease of which crop?

Ergot disease of cumbu (pearl millet) is caused by

Which weed acts as an alternate host for blast disease in rice?

Rice blast is characterized with

Consider the following statements:
I. Sulphur is the oldest fungicide used in plant disease control.
II. Sulphur is a contact and protective fungicide effective against powdery mildews and rusts.