Symptoms:
- Minute flecks are appeared on both sides of leaves.
- Circular to elongate cinnamon brown, powdery, erumpent pustules on both leaf surfaces
- As the crop matures brownish black pustules develop
- In severe cases infection spreads to sheath and other parts
Pathogen:
- Puccinia sorghi is a heteroceious rust.
- Uredospores single celled, echinulate, yellowish brown, pedicellate, elliptical
- Teliospores reddish or brown in colour, two celled, rounded at the apex
- Alternate hosts - Oxalis europea, O. corniculata and O. stricta
- Basidiospores infect Oxalis corniculata, where pycnial and aecial stages occur
- Aeciospores carried by wind and infect maize
Favourable condition:
- Cool, warm and moist weather (15 - 25o C)
Survival and Mode of Spread:
- Primary spread through alternate hosts
- Secondary spread through wind borne uredospores
Management:
- Remove the alternate hosts .
- Collect the remains of the crop and destroy by burning or burying
- Foliar spray of kresoxim-methyl 44.3% SC @ 1 ml/l or tebuconazole @ 1ml/l orchlorothalonil or mancozeb 2 ml/l at 35 and 50 DAS
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Brown pustules on leaf |
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