Ergot of Rye PDF
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Uploaded by CommendableSard7063
Loyola College
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Summary
This document explains ergot of rye, a plant disease caused by *Claviceps purpurea*. It describes the symptoms, host range, disease cycle, and importance of the disease in agriculture. Control measures are also mentioned.
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## ERGOT OF RYE **(9)** **Causal organism:** *Claviceps purpurea* (Class-Pyrenomycetes, sub-div. Ascomycotina). **Host:** Rye, wheat, oat, barley, etc. **Symptoms:** The symptoms of ergot disease appear in the inflorescence (ear) where the contents of ovaries are replaced with cottony mycelia...
## ERGOT OF RYE **(9)** **Causal organism:** *Claviceps purpurea* (Class-Pyrenomycetes, sub-div. Ascomycotina). **Host:** Rye, wheat, oat, barley, etc. **Symptoms:** The symptoms of ergot disease appear in the inflorescence (ear) where the contents of ovaries are replaced with cottony mycelia bearing conidiophores and conidia. Finally the grains are replaced by hard horn-shaped purplish Sclerotia protruding out between the glumes and the spikelet as dark spurs on the spike. **Host Parasite Relationship:** Filamentous, branched and septate mycelium is mainly confined to the ovaries of the flowers. It destroys the tissues and reduces the yield. **Disease cycle**: The disease is air-borne. The sclerotia fall on the ground and germinate to produce many stomata with globose heads. These heads bear a number of perithecia, which contain a number of long club-shaped asci containing ascospores. The ascospores germinate on flowers of host plant. They produce germ tubes which penetrate and ramify in the ovary. Soon the mycelium starts producing conidiosphores and conidia, which help to spread the disease. **Importance of disease:** The horn-shaped sclerotia are also called ergot. These contain some alkaloids. The consumption of ergot causes ergotism disease to man and domestic animals. The disease results convulsions, paralysis, hallucination and finally death to man. Cattles also suffer with the disease when they eat ergot grains. The ergot is widely used in midwifery to assist delivery. **Control:** 1. Use of sclerotia free grains for sowing. 2. Crop rotation. 3. Use of resistant varieties with short flowering period. **Figure 12.12:** Ear of rye showing sclerotia caused by *Claviceps purpurea*. **Sclerotium** **Ear**
