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.

Read More

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.

Read More

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.

Read More

मेरी कलम 02:27  No comment