SEASONAL VARIATION. Determination of the periodic composition of the leaf surface mycojlora.

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1 SEASONAL VARIATION Determination of the periodic composition of the leaf surface mycojlora. Raipur city is the capital of Chhattisgarh. Its cardinal points Nand 82o-38 E. In the present investigation, periodic variation were studied mainly in three seasons, Summer (March to June), Rainy (July to October) and Winter (November to February). The leaf surface mycoflora is a natural habitate which represents heterogenous population of both pathogens and non pathogens. The study ofleaf surface mycoflora carries special significance owing to periodic changes and consequent fluctuation of the population of microorganisms on plant surface. The plant surface possesses a sufficient potential to sustain a sizeable microflora of both parasitic and non parasitic. A considerable interest lies therefore in the investigation of the types of micro-organisms which occur on the leaf surface mycoflora during the changing metrological factors at various phases of plant growth speculation, as to the reasons for differing patterns of phylloplane colonization have included suggestions such as variations in temperature, humidity rain fall, wind velocity and phenology oflocal vegetation. Nutritional demands of fungi differ frequently. This may be true for the closely allied species or the varieties of the same species. The leaf surface micro-organisms are to a large extent influenced by the plant species, the nature of exudates/ extracts, physiology and diseased condition of the plant. The fungus population was not homogenous on the leaf surface through out the year and shows periodic variation or seasonal variation probably due to the plant, size of leaf, climatic factors and available nutrients on the leaf surface. Qualitatively over a11321 colonies were identified under 35 fungal types belonging to 23 genera during investigation period March 2004 to February Out of total fungal organisms 4.36% belonged to Zygomycotina, % Ascomycotina 61.68% Deuteromycotina and 3.42% belong to Mycelia sterilia (Table no.04, Fig.No.3). Maximum fungi ie 31 were isolated during winter, moderate 21 during rainy and minimum 16 during the summer season (Table No.7,Fig. No.7) Summer season:- Quantitatively over all 55 colonies were identified under 16 fungal types which belong to 11 genera during investigation period March 2004 to June The percentage contribution of fungal flora was Zygomycotina-1.8%, Ascomycotina-54.54%, Deuteromycotina % Mycelia sterilia-3.63%. 22

2 (Table no.04, Fig. 2-A ) Highest fungi were recorded from March 2004(9) and the lowest number of fungi (5) were encountered in the month of May 2004.(Table no.07, fig. 06) Aspergillus niger was dominant through out the summer season Aspergillus jlavus, Aspergillus fumigatus, Curvularia lunata as codominant species. Rainy Season-: The study of leaf surface mycoflora on rainy season indicated that presence of a total of 105 colonies were identified under 21 fungal types which belonged to 17 general. Out of total 21 fungal species which Constitute - 3.8%, Zygomycotina-38 %, Ascomycotina-56%, Deuetromycotina and 1.9% Mycelia sterilia (Table no.04, Fig. No.2-B ). During rainy season maximum number of fungi (12) were isolated in the month of October while minimum number of fungi (9) were recorded in the month of July and August(Table no.07, fig.no.06) some fungi as Fusarium solani, Aspergillus niger, Pestolotia versicolor were recorded as dominant fungi, Aspergillus nidulans, Fusarium oxysoporum, Curvularia lunata, Cladosporium cladosporioides, Cheatomium globosum were recorded as codominant species. Winter Season :- A total number of 161 colonies were identified under 30 fungal types 20 genera during investigation period Nov.2004 to Feb The fungi recorded in winter season from leaf surface belong to 5.59% Zygomycotina, 17.34% Ascomycotina, 72% Deutero mycotina, 4.34% Mycelia sterilia, (Table no. 04, Fig.No.2-C) During winter season highest number of fungal species 19 were recorded in the month of January 2005 while lowest number (12) were encountered during the month offeb.(2005).(table no.07, fig. no. 06) Some fungi as Alternaria alternata, Pestolotia versicolor, Cladosporium cladosporioides, Bispora pusiella, Fusarium oxysoporum were recorded as dominant species while Aspergillus niger, Aspergillus fomigatus, Penicillium nigricans, Trichoderma viridae, Curvul(lria lunata were isolated as codominant species The result indicates that some fungi were common in all three season such fungi includes Aspergillus niger, Aspergillus nidulans, Aspergillusfomigatus, Cladosporium cladosporioides, Curvularia lunata, Fusarium oxysoporum, Penicillum nigricans and Alternaria alternata. In the present investigation period some fungi were present in more than one season but not in all three season Aspergillus terreus (S.R.), Fusarium monliformae (R.W.), Fusarium so/ani (R.W.), Rhizopus stolonifer (S.W.), Mucor racemosus (R.W.), Phoma glomerata (R.W.), Curvularia clavata (R.W.), Bispora pusiella (R.W.),Cladsporium herbarum(s. W.), Helminthosporium australiense(r. W.), Memnoniel/a echinulata (R.W.), Monodictys glauca(r.w), Nigrospora oryzae (R.W.), 23

3 Paeci/omyces varioti(s.w.), Pestolotia versicolor (R.W.), Scyta/idium thermophilum(s.w.) and Trichoderma viridae (S.W.). Certain fungi were exclusively recorded from only one season such as Cunnighme//a echinulata, Chaetomium globosum, Alternaria, chlamydospora, Alternaria tenuis,stenella aragua/a andtrichoderma herbarum in winter season, Haplosprella ipomoeae in rainy season. 24

4 Periodic Composition of Air Mycoflora The atmospheric fungal population is not homogenous through out the year and show seasonal or periodic variation. Fungal spores are one of the major biotic constituents of atmosphere known to have allergic properties, pathogenic,nonpathogenic and act as organic pollutants.the fungal populations is not homogenous through out the year and shows periodic variation. The present study was carried out at Raipur over Turmeric crop from March 2004 to Feb Qualitatively overall618 colonies were identified under 32 fungal types which belong to 20 genera. During present investigation period, out oftotal microorganisms 0.809% were found to be of Zygomycotina 24%, Ascomycotina 72.9%, Deuteromycotina and 2% Mycelia sterilia (Table no.os, Fig. No. 12). Maximum number (29) were isolated during the winter season, moderate (25) during rainy season minimum number of fungi ( 16) were isolated during summer season (Table no.l2, Fig. no.l6) Summer season -: During the study period the lowest number of fungal colonies were recorded in the month ofmarch to June Qualitatively over a11115 colonies were identified under 16 fungal species under 8 genera during summer season. The percentage contribution ofzygomycotina was nil, Ascomycotina 50%, Deuteromycotina 46.9%, Mycelia sterilia 2.6%. (Table no. 08, Fig. No.11- A).Maximum number of fungal species ( 1 0) were isolated in the month of March while minimum number of fungal species ( 5) were isolated during the month of May.(Table no.12, Fig. no.15) Aspergillus niger andaspergillusfomigatus were dominant through out the summer season while Cladosporium cladosporioides, Nigrospora oryzae, Trichoderma viridae Aspergillus flavus, Aspergillus terreus were found to be codominant species. Rainy season -: The investigations of air fungal spora on rainy season indicated a presence of, a total of231 fungal colonies under the 25 fungal species and under the 17 genera of which the fungi constituted Zygomycotina 0.43%, Ascomycotina 20.3%, Deuteromycotina 78.3% and Mycelia sterilia 0.864% (Table no.os, Fig. No. 11-B ). During rainy season maximum number of fungi was isolated in October (16) while the lowest in the month of July (12).(Table no.12, Fig. no.15) Aspergillus fumigatus, Aspergillus niger, Cladosporium cladosporioides, Pestolotia versicolor Fusarium solani, Bispora pusiella, Curvularia lunata, were dominant species. Macrophoma phaseolina, Monodictys glauca, Fusarium moniliformae, were codominant species 25

5 Winter season-: A total number of 272 colonies were found during winter season from November 2004 to February 2005 and identified 31 fungal species under 19 genera. The fungi recorded from air of winter season belonged to % Zygomycotina, 17.6% Ascomycotina, 79.4% Deuteromycotina and 2.9% Mycelia sterilia (Table no.08, Fig. No. 11-C). During the winter season, highest number of fungal species (20) were recorded during the month of January while lowest number( 15) were present during the month offebruary. (Table no.l2, Fig. no.l5). Some fungi such as Alternaria alternata, Alternaria tenuis, Fusarium oxysoporum, Monodictys glauca, Cladosporium cladosporioides, Pestolotia versicolor were dominant species. Nigrospora oryzae, Helminthosporium australiense, Aspergillus niger, codominant species. The result indicates that some fungi were common in all the three season. Such fungi includesaspergillusfumigatus, Aspergillus nidulans, Aspergillus niger, Aspergillus terreus, Cladosporium cladosporioides, Fusarium oxysoporum, Fusarium so/ani, Nigrospora oryzae, Trichoderma herbarum and Trichoderma viridae, Mycelia sterilia black. In the present investigation period, some fungi were present in more than one season but not in all the three seasons. Aspergillus flavus(s.w.), Aspergillus sulphureous(s.w.), Cheatomium globosum(r.w.), Alternaria alternata(r.w.), Bispora pusiella (R.W.), Cladosporium herbarum(s.r.), Curvularia lunata aeriata(r.w.), Fusarium monliformae (R.W.), Helminthosporium australiense (R.W.), Macrophoma phaseolina(r.w.), Monodictys glauca(r.w.), Paecilomyces varioti (S.W.), Pestolotia versicolor(w.r), Phoma glomerata(r.w.), Phoma herbarum (R.W.), Mycelia sterilia white (R.W.). Mucor racemosus (R.W.). Rhizopus stolonifer were present only in winter season. Alternaria chlamydospora and Alternaria tenuis also present in winter season. (S.)- Summer (R)- Rainy (W)- Winter 26

6 Correlation of their periodic composition The population of leaf surface mycoflora and air mycoflora varies due to different climatic conditions. In plant pathology, fungi and bacteria are important cause of disease and are usually spread by the action of wind or by rain splash (Gregory, 1973). Fungal spores are almost, always present in the air although their number and types vary with time, days, season, geographical location and variable local spore sources. The air borne micro-organism particularly pollen and spores are capable oftrapping and carrying various inorganic particulates from one place to another (Nilson, 1992). The aerobiological process comprises five main steps source, release, flight deposition and impaction. Each step is affected by enviommental factors (Nilson, 1992). The airspora will eventually fall down towards the ground. There are two main types of deposition, dry deposition and wet deposition. Precipitation, brings down the airspora from the upperlayer and therefore helps in cleaning the atmosphere at the same time. The deposited airspora are more or less retained by the substrate or impacted on various receivers pollinating or some times causing injuries or disease (Nilson, 1992). Qualitatively, over all (321) colonies were identified on leaf surface while 618 fungal colonies were identified in air, but maximum number of genera(23) and species(35) occurred on leaf surface with respect to air(32)fungal species and (20) genera. Summer season-: Qualitatively, over all (55) fungal colonies were present on leaf surface while (115) fungal colonies occured in air, both on leaf surface and in airmycoflora (16) species were present but they come under (11) genera on leaf surface and (8) genera in air. The percentage recorded in Zycomycotina 1.8%, Asomycotina 54.54%, Deuteromycotina 39.9% and Mycelia sterilia 3.6%,on leaf surface while Zygomycotina was nil in air, Ascomycotina 50%, Deuteromycotina 46.9%, Mycelia sterilia 2.6%. Minimum fungal species were present in the month ofmay, both on leaf surface and in air. Aspergillus niger were dominant fungus in both. Rainy season-: In rainy season, (1 05)fungal colonies were present on leaf surface and (231) fungal colonies were present in air. In air mycoflora (21) fungal species were present under ( 11) genera while (25) fungal species were present under (21) genera on leaf surface which constitute Zygomycotina 3.8% and 0.43% on leaf surface and in air respectively. Ascomycotina 38% on leaf surface and 20.3% in air,deuteromycotina 56% on leaf surface and 78% in air, Mycelia sterilia 1.9% on leaf surface and 0.8% in air. Aspergillus niger was found to be dominant on leaf surface mycoflora while Cladosporium cladosporioides were dominant in air. Codominant species were Aspergillus fumigatus, Fusarium so/ani present on 27

7 leaf surface and Aspergillus fumigatus, Aspergillus niger, Curvularia lunata and Pestolotia versicolor were codominant in air. Winter season -: Total number of (161) fungal colonies were present on leaf surface while (272) present in air. (30) fungal species under (21) genera on leaf surface while (29) fungal species present under (19) genera in air. Percentage contribution of Zygomycotina 5.5%, on leaf surface 1.4% in air Ascomycotina 17%, on leaf surface and 17.6% present in air, Deuteromycotina 72% and 79% on leaf surface and in air. Mycelia sterilia present 4.3% on leaf and 2.9% in air. Alternaria alternata Pestolotia versicolor dominant species and codominant species were Bispora pusiella, Cladosporium cladosporioides on leaf surface. In air Pestolotia versicolor, Alternaria alternata, fusarium so/ani and Cladosporium cladosporioides were dominant fungal species and Alternaria tenuis was the codominant species. S- Summer, R- Rainy, W- Winter 28