Anthracnose of Sweet Sorghum
(Colletotrichum graminicola (Ces.) Wilson)
- The foliar symptoms of anthracnose appear 30-40 days after emergence.
- Typical symptoms are small, circular, elliptical or elongated spots usually about 5mm in diameter. These spots develop gray to straw-colored centers with wide margins that may be tan, red, or blackish -purple depending on the cultivar and the pathogen population. Under conditions of high humidity, the spots increase in number and coalesce to cover a larger leaf area.
- The pathogen also infects midrib, leaf sheath and panicles including grains and rachis.
- Variation in foliage and grain symptoms may be due to host reaction, host physiological status, and the prevailing weather conditions.
Fig 1: Syptoms on the leaf
- Grow anthracnose resistant cultivars, such as SPV 386, SPV 422, NTJ 2 ICSV 247, CSH 25 and CSH 22SS
- Spraying Captafol 0.2%, benlate or carbendazim (0.5kg ha-1), three sprays at 10-day intervals starting from 30 -day old crop, under rain free conditions.