Three new fungal diseases from India

During systematic survey of parasitic fungi of Faizabad (U.P.), the authors observed leaf spot disease of Desmodium gyrans (Cercospora canescens), Phragmites communis (Alternaria tenuissima) and a foot rot disease of Coriandrum sativum (Torula herbarum f. quaternella) caused by fungi given in the parenthesis. The specimen has been deposited in the Herbarium, Commonwealth Mycological Institute, Kew, England and a part of the collection has been deposited in the Mycological Herbarium, Botany Department, K.S. Saket Post-Graduate College, Faizabad. Symptoms of each disease are briefly given below. 

1. Leaf spot disease of Desmodium gyrans:

The disease was confined to the lower surface of the leaves. Spots were diffused, irregular, light brown to black, scattered all over the leaf surface, however, the vein areas being heavily infected. On the basis of detailed morphological characters the causal organism was identified as Cercospora canescens Ell. & Mart. 

Collected from Gokul Sadan, Ayodhya, Faizabad, March 1973, IMI 181834.

2. Leaf spot disease of Phragmites communis:

The plants were infected to various degree. The infection was more severe on younger parts of the growing tips of aerial shoot including leaves. The apical portion was damaged which ultimately died. The older leaves showed black to brown spots of irregular size on outer surface of leaf sheath and on lamina. 

The detailed morphological characters revealed the the fungus responsible for the disease was Alternaria tenuissima(Kunze ex Pers.) Wiltshire.

Collected from Nayaghat, Ayodhya, Faizabad, Feb. 1976, IMI 209295.

3. Leaf spot disease of Coriandrum sativum:  

 The disease started as greyish patches scattered here and there on stem and older leaves. Later on the entire plant was involved including flower and fruits. Severely infected plants in advanced stage showed wilting and final rotting. 

Microscopic studies on diseased part of the plant revealed that Torula herbarum (Pers.) S.F. Gray f.quaternella Sacc. was the causal organism. 

Collected from Rsam Kote, Ayodhya, Faizabad, Feb. 1976, IMI 209326.

So far, none of the above mentioned diseases have been recorded from India (Butler and Bisby, 1954; Mukerjii and Juneja, 1974; Tondon and Sudhir Chandra, 1964; Tilak and Rao, 1968), and these are thus new diseases of concerning plants from India.  

Cited this as: Kanaujia R.S., Kishor R. and C.S. Singh (1978): Three new fungal diseases from India. Acta Botanica Indica. 6: 92-93.

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मेरी कलम 06:33  No comment

A new Aspergillus storage rot of Mandarin orange in India

Apparently, the fruits appeared quite normal. When ring was removed, a thick mycelial mat was found along with the heavy sprouting of conidia of the fungus particularly at the placental region. The infection gradually penetrated the deeper regions of the fruit and within 5-6 days entire fruit was involved and become rotten. The pathogenecity tests gave positive results. The fungus was cultured on PDA and identified to be Aspergillus aculeatus Iiz. Earlier A. aculeatus has not been found on Citrus reticulata fruits causing soft rot in India. The specimen has been deposited at the Department of Botany, K.S. Saket P.G. College, Faizabad as Accession No. RSK -306.

Cited this as:  Kanaujia R.S. (1979): A new Aspergillus storage rot of Mandarin orange in India. Indian Phytopathology. 32(4): 620-621.

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मेरी कलम 02:15  No comment

A Modified Approach in Substrate Preparation Technique for Small Scale Oyster Mushroom Farming

Aims: Cultivation of oyster mushrooms has increased vastly in a global scale during last few decades. Contaminants and indigenous microflora present in the substrate may led to the low productivity of mushrooms. Keeping this in mind, the present study was under-taken with slight modification in substrate preparation technique to eliminate dust particles from the substrate and to assure contamination free mushroom production. 

Study Design: Comparative evaluation between modified approach and control beds. 

Place and Duration: The study was carried out in Shri Laxman Prasad Pyare Lal Agro Products, Ayodhya during 2017. 

Methodology: The wheat straw substrate was immersed in the drum containing tap water, mixing properly and allowed to stand for 10-15 min to settle down the dust particle in the bottom of drum. After that, the floating substrate was transferred to the slant surface so that the extra water was decanted off. This substrate was put in to the steam sterilized gunny bag and steeped in the chemical solution consisting of Formaldehyde (500 ppm) and Bovistin (75 ppm) for 18 h.  For the control, fresh wheat straw was put in to the steam sterilized gunny bag and steeped directly in the chemical solution as suggested above. After removal of excess water, the substrate was used for spawning with inoculums of Pleurotus sajor-caju, Strain- Malaysia. 

Results: Beds with modified approach showed complete absence of contaminants during entire crop cycle which showed the effectiveness of modified method while beds treated as control showed little incidence of various contaminants viz., Alternaria alternata, Aspergillus fumigatus, Curvularia sp., Penicillium sp., and Rhizopus stolonifer with 6.67-20.00 percent incidence. 

Conclusion: The results revealed that modified method should be considered to contamination free mushroom production. (PDF)

Cite this as:  Siddhant, O.P. Ukaogo and S.S. Walakulu Gamage (2018). A Modified Approach in Substrate Preparation Technique for Small Scale Oyster Mushroom Farming. Asian Journal of Agricultural and Horticultural Research. 2(2): 1-5.

     

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मेरी कलम 06:21  No comment

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