A new leaf spot disease of Nyctanthes arbor-tristis caused by Myrothecium verrucaria from India

During systematic survey of parasitic fungi at Faizabad (U.P.), author came across a new leaf spot disease of harsingar (Nyctanthes arbor-tristis L.) caused by Mycothecium verrucaria (Alb. & Schw.)Ditam. ex Fr.

The small spherical yellowish leaf spots become visible in the month of September. With time the spots increase in size and finally become greyish followed by light brown and the death of the leaf tissues.  

The pathogen was isolated on PDA medium by usual method. Healthy leaves when inoculated artificially by spore suspension, developed spots characteristics in nature after 15 days. Reisolations of the artificially infected spots yielded Myrothecium verrucaria.

The morphological obsrvations were made in culture and in nature. The mycelium is septate, white to olive green and become olivaceous black with ageing. Conidiophore about 70-78 µ long, smooth, erect, septate and brached above penicillately producing conidia borne in chains, directly and on phialids. Conidia elongate, to ovate, smooth, dusky, olive green to olivaceous black and about 6-9.7X1.46-4.0 µ. 

On the basis of morphological characters the fungus was identified as Myrothecium verrucaria (Alb. & Schw.) Ditm ex Fr.

Myrothecium verrucaria  has earlier been reported from soil and perhaps not as parasite hence this has been described as a causal organism of leaf spot disease of N. arbor-tritis L. earlier not reported from India.

This fungus has been deposited in the Herbarium CMI as IMI. 209313 and Herbarium K.S. Saket P.G. College,Faizabad as RSK-154/S.

Cited this as: Kanaujia R.S. (1977):  A new leaf spot disease of Nyctanthes arbor-tristis caused by Myrothecium verrucaria from India. Indian Phytopathology. 30(2): 291-292.

 

 

 

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मेरी कलम 23:50  No comment

Notes on new fungal disease of Solanum tuberosum

In February, 1979, The author noticed stems of Solanum tuberosum L. infected by a fungus causing severe necrosis in his kitchen garden. On examination, the causal organism of the disease was identified as Mucor heimalis Wehmer. Earlier S. tuberosum has not been found to get infected by Mucor heimalis in India and this is new report. 

The disease appeared as small moist area on the stem just above the soil. The lesion enlarged radially and showed fluffy growth of fungus within a week followed by stem necrosis and ultimate death of plants desiccation. The pathogenicity tests were carried out as follows.

The stem of 15 days old potato plants were separately sprayed with spore suspension of freshly sporulating culture of Mucor heimalis without, and after making the injuries on the test plants. The sprayed plants were incubated in the field conditions. After 10 days, the characteristic disease spots were found on the stems in the plants which were injured before inoculation. Reisolation from the artificially infected plants gave Mucor heimalis, thus, the pathogenic nature of the fungus was confirmed by inoculation tests providing Koch's postulates.

Cited this as: Kanaujia R.S. (1979): Notes on new fungal disease of Solanum tuberosum. Indian Phytopathology. 32(4):611-612.

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मेरी कलम 23:13  No comment

Effect of extraneous matter on juice extraction and Pol% cane

The present study was carried out in the month of March, April and May consisting three elite sugarcane varieties, viz., CoS 8436, CoS 8432 and CoSe 92423 to evaluate the effect of extraneous matter (trash) on extraction % of juice and Pol% cane. The result revealed that the extraneous matter affected extraction % and Pol% cane adversely, at a significant level both at the varietal level as well as at staling hours. Both the aforesaid parameters decrease with the increasing months along with the data calculated over the varieties, therefore, it was concluded that the cane should be free from all the extraneous matter to get maximum juice and sugar from cane.

Cited this as: Siddhant, Srivastava R.P. and O.P. Ukaogo (2018): Effect of extraneous matter on juice extraction and Pol% cane. 41st Annual International Conference, Workshop and Exhibition on chemical sciences in an emerging economy: Issue, prospects and opportunities organised by University of Ibadan, Ibadan, Nigeria. September 16-21, 2018. p. 26.

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मेरी कलम 03:48  No comment

A new fungal disease of Phlox drummondii in India

During March, 1976, the infected leaves of Phlox drummondii  were collected from Govt.Garden Faizabad. On examination Melanospora zamiae Corda was identified as causal organism. Earlier this fungus has not been found causing a disease on P. drummondii in India. 

The spots appeared to be earthy grey to light brown, irregular, not exceeding 0.5 cm square area of the leaf on the ventral surface. Artificially infected healthy plants of Phlox drummondii developed characteristic disease spots within 16-20 days. Reisolations from artificially produced spots gave Melanospora zamiae. 

The specimen has been deposited in the Herbarium Commonwealth Mycological Institute, England (IMI 210695).

Melanospora zamiae Corda has only been reported on dead leaves of Artocarpus incisa L from Bangalore by Ponnappa (1970) and , therefore, the present case is a new fungal host association for India. 

Cited this as: Kanaujia R.S. and R. Kishore (1980): A new fungal disease of Phlox drummondii in India. Indian Journal of Mycology and Plant Ptathology. 10 (1): 72.

 

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मेरी कलम 05:55  No comment

Fungi on decomposing spadix of Pandanus fascicularis

Investigation into fungi causing deterioration of different parts of the shoot have been made by Hogg and Hudson (1966), Hudson and Webster (1958), Kamal and Singh (1970), Webster (1957) and Yadava (1966). Such studies on the modified part of the shoot are scarce and scanty. Undoubtedly, some fragmentary reports in connection with the floral infection of one or the other part of the flower, though available; yet are the local interest (Plate and Schineider, 1966; Schonbeck, 1967 and Welfswinkee, 1966). The present study is an attempt to explore the organisms associated with the spadix of Pandanus fascicularis when it is still enclosed within the spathe and their role in its decomposition.

Spadix of Pandanus fascicularis still enclosed within the spathe were plucked from the Janaki ghat, Ayodhya, district Faizabad and were brought to the laboratory in sterilized brought mouth polythene bottles. The were then incubated in Petri-dish moist chamber (15cm) at room temperature. Sterilized water were added to the moist chamber when needed. The observations were made on the 3rd, 5th, 10th, 15th, 20th, 30th,40th and 50th day of incubation and the fungi were recorded by direct observation of maturre fruit bodies under the dissecting microscope, where their presence and absence was the criterion of colonisation of the organisms on different days of incubation. 

Perusal of the data in the Table I shows the presence of only deuteromycetes comprising Aspergillus species, Curvularia lunata and Trichothecium roseum on decomposing spaxis of P. fascicularis. Of Aspergillus  species, A. fumigatus, appeared on the 3rd day and was accompanied by A. aculeatus A. flavus, A. phoenicis and A. ochraceous on the 5th day. Four amongst them were recorded upto 15th day while one (A. flavus) persisted till the 20th day of incubation. Curvularia lunata  appered on the 10th day and persisted upto 50th day. It was accompained by Trichothecium roseum on the 30th day which persisted till the last day of observation.

      Table I. Species on Spadix incubated upto fifty days.

Fungal Species	DAYS OF OBSERVATIONS
	3	5	10	15	20	30	40	50
Aspergillus aculeatus	-	+	+	+	-	-	-	-
A. flavus	-	+	+	+	+	-	-	-
A. fumigatus	+	+	+	+	-	-	-	-
A. ochraceous	-	+	+	+	-	-	-	-
A. phoenicis	-	+	+	+	-	-	-	-
Curvularia lunata	-	-	+	+	+	+	+	+
Trichothecium roseum	-	-	-	-	-	+	+	+

    

Nature and environmental conditions of the microhabitat exercise a broadly selective effect upon the kind of microorganisms that enter into competition for the substrate (Garrett, 1963). Definite correlation appears between the substrate and type group of fungi colonising it. Abundance and the rare occurrence of the species are governed by the composition of the substrate and their association with micro-entities which may be stimulating or antagonistic to their growth at same nutritional level. Deuteromycetes are a group of indefinite affinity with varying nutritional requirements. Ecologically, however, sugar fungi include a number of imperfect fungi specially the species of Aspergillus and Penicillum (Cochrane, 1958). The species of this group are basically considered as cellulose decomposing (Siu and Reese, 1953). In the present investigation, the early appearance of aspergilli may be deu to the ability to utilise simple sugars and rapid spore germination (Table. I). Carter (1958) reported that a diffusible heat-labile substance produced by bacteria, isolated from pellets inhibited the growth of phycomycetes in culture. The absence of phycomycetes from the decomposing spadix may be affected by the antagonistic effect of bacteria. Occurrence of  C. lunata and T. roseum  during the last days days of incubation may be ascribed to thier ability to utilise cellulose (Siu and Reese, 1953).

The successional pattern of fungi, associated with the decomposing unbloomed spadix of P. fascicularis was studied. Species of Aspergillus appeared 1st, followed by Curvularia lunata. Trichothecium roseum appeared late and persisted till the last day of observation. (See original)

Cited this as: Kanaujia R.S. and C.S. singh (1975): Fungi on decomposing spadix of Pandanus fascicularis. Botanique. VI(1):11-15.

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मेरी कलम 07:19  No comment

Mushroom Awareness Program at Ayodhya (Part-2)

Just like the year 2016, this year too we had organized a mushroom awareness programme under the banner of Sri Laxman Prasad Pyare Lal Agro Products, Ayodhya during the month of February to March, 2018, In which many talented students of various institutions have participated. Our aim toward this programme was to develop research aptitude among the students. During this programme, the students were not only acquainted with the experiments going on in the mushroom unit but also they were made familiar with the various dimensions of mushroom production technology. The experiments based on the animal wastes and various types of papers were the central attraction for the students.
   

Students from Chandra Coaching classes during mushroom awareness programme

On this occasion, Mr. Mahesh Kumar (Biology teacher at SRKMK School) Mr. Suwan Srivastava (Founder Chandra Coaching classes) and Mr. Kamesh Mani Pathak were also be present.

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मेरी कलम 00:18  No comment

Notes on an unrecorded fungal disease of Manihot esculenta

During November, 1978, The author collected leaves of Cassava (Manihot esculenta) Crantz severely infected by a leaf blight disease from a kitchen garden at Bareilly. On examination, the associated fungus was identified as Aspergillus niger  Van Tieghem. This appears to be a new host-fungal association for India. The specimen has been deposited with the Department of Botany, K.S. Saket Post Graduate College, Faizabad under No. RSK-299. 

The disease appears along the midrib of the leaves on the ventral side as irregular narrow light gray spots which enlarge with the advance of time. In one or two weeks, the colour of spots changes to light black due to heavy sprouting of the conidiophores and conidia, resulting in blighting and nacrosis along midrib of the lamina. In 3-4 weeks, the whole leaves gets involved and drops off. Both young and old leaves were equally infected by the fungus. The pathogenicity tests gave positive results and characteristic disease spots were artificially developed in 2-3 weeks.

Cite this as: Kanaujia R.S. (1979): Notes on an unrecorded fungal disease of Manihot esculenta. Indian Phytopathology. 32(3): 464-465.

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मेरी कलम 02:27  No comment