Ergot of Rye PDF - Plant Diseases
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Uploaded by CommendableSard7063
Loyola College
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Summary
This document discusses *Ergot of Rye*, a plant disease caused by the fungus *Claviceps purpurea*. It explains the symptoms, host range, disease cycle, and control methods. The document also highlights the importance of avoiding consumption of ergot as it can lead to ergotism in humans and animals.
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### (9) ERGOT OF RYE **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 bearin...
### (9) ERGOT OF RYE **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 in convulsions, paralysis, hallucination and finally death to man. Cattle 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*.