Wet rot disease of Cereus hexagonus and fruit rot of Syzygium cumini, new to India

During an extensive survey of fungi from Faizabad (U.P.), the author came across two important diseases, viz., wet rot of Cereus hexagonus caused by Periconia byssoides Pers ex Me'rat and fruit rot of Syzygium cumini (L.) Skeels caused by Rhizopus nigricans Ehrenb. ex Corda, new to India. The specimen has been deposited in the Department of Botany, K.S.S. P.G. College, Faizabad under Accession No. RSK 415 and 558. The brief description of the disease is given below: 

Wet rot disease of Cereus hexagonus:

(Caused by Periconia byssoides Pers ex Me'rat, Collected from Ayodhya. Feb 17, 1979)

              The unbloomed floral buds due to open in 5-6 days showed small, numerous water soaked area on outer surface of hypanthium. Thy enlarged irregularily and involved the entire outer surface of the perianth followed by the formation of light gray conidiophores and condia within 4-5 days. The floral bud became pulpy and finally shed off.

Fruit rot of Syzygium cumini (L.) Skeels:

(Caused by Rhizopus nigricans Ehrenb. ex Corda; Collected from local fruit market at Ayodhya; June 08, 1980)

               The disease started as small water soaked areas on fruit surface particularly near placental region. The entire fruit surface was covered within 48 hours thereafter, the fruit became soft and pulpy. 

Periconia byssoides and Rhizopus nigricans have been found to cause rot disease in number of plants but not on related hosts described above. This is a new report for country. (PDF Copy at Slideshare.net)

Cited this as: R.S. Kanaujia (1982): Wet rot disease of Cereus hexagonus and fruit rot of Syzygium cumini, new to India. Indian Journal of Mycology and Plant Pathology. 12(3):323.

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मेरी कलम 05:22  No comment

Sclerotial rot of Stapelia gigantea new to India

Stapelia gigantea, an ornamental succulent of family Asclepiadaceae was observed infected by a rot in Ayodhya of Faizabad district during September 1979. The fungus was isolated on PDA medium and was indentified as Sclerotium rolfsii Sacc. The specimen has been deposited in the Department of Botany, K.S.S. P.G. College, Faizabad (Accession No. 649). 

The disease stars as small pin head size, black submerged spots near the ground which gradually enlarge and merged together to form irregular larger patches. The spots progress upward and within a fortnight involve the entire plant that by this time shows characteristic dry rot. The pathogenecity test performed by standards methods gave the positive results.

Sclerotium rolfsii is known to cause rot disease of Dianthus sp, Delphinium ajacis and Polyanthus tuberosa and Zinnia in India. Its association with Stapelia gigantea is a new record. (PDF copy at Slideshare.net)

Cited this as: R.S. Kanaujia (1982): Sclerotial rot of Stapelia gigantea new to India. Indian Journal of Mycology and Plant Pathology. 12(3):328.

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मेरी कलम 03:30  No comment

Record of Periconia byssoides on Four 'O' clock plant from India

In September, 1978, the author observed plants of Mirabilis jalapa L. infected by wet disease at Faizabad. On examination the pathogen responsible for the disease was found to be Periconia byssoides Pers. ex Me'rat. The disease starts as a small gray patch at the nodes. The colour of infected region gradually changes to light brown due to the production of codiophores and conidia of pathogen. Within 12-15 days of infection the region of the plant above infected nodes showed wilting, finally the rotting and droping of the plant above it. The specimen has been deposited in the Department of Botany, K.S.S. P.G. College, Faizabad as Herbarium No. RSK-260. The present case is a new host record for India.  (PDF copy at Slideshare.net) 

Cited this as: R.S. Kanaujia (1982): Record of Periconia byssoides on Four 'O' clock plant from India. Indian Journal Mycology and Plant Pathology. 12(2): 243.

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मेरी कलम 23:22  No comment

Periconia rot of Capsicum annuum in India

Periconia byssoides is known to parasite a number of plants in India but so far not reported on Capsicum annuum L. The small spherical to irregular spots of light brown colour gradually enlarged and merged subsequently to form continuous dark brown to black patches on stem, leaves and fruits. The whole plant were soon infected and ultimately dried within 20-25 days. The damage was about 70-85 per cent. The fungus was isolated on PDA medium by usual methods. The specimen has been deposited (No. RSK-142) in the herbarium of Botany Department, K.S.S. P.G. College, Faizabad. (PDF copy at Slideshare.net)

Cited this as: R.S. Kanaujia and R.S. Verma (1979): Periconia rot of Capsicum annuum in India. Indian Phytopathology. 32(3): 445.

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मेरी कलम 01:31  No comment