International Journal of Research in Botany. ISSN Original Article

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1 Available online at International Journal of Research in Botany Universal Research Publications. All rights reserved ISSN Original Article STUDIES ON SEED MYCOFLORA ASSOCIATED WITH DIFFERENT VARIETIES OF COTTON (Gossypium sp. viz.; G. arboreum, L., G. barbadense, L., G. herbaceum, L. and G. hirsutum, L.) Anil Kumar Kushwaha Department of Botany, D.B.S. College, Kanpur Received 08 May 2014; accepted 26 May 2014 Abstract Seed washing test used to detect the external mycoflora of different varieties of cotton viz. Gossypium arboreum, L. G. barbadense, L., G. herbaceum and G. hirsutum, L. seeds. In viability test 75.0 to 90.0 per cent spores of Alternaria brassicicola, 60.0 per cent to 75.0 percent spores of Aspergillus niger and 80.0 to 85 per cent spores of Fusarium oxysporum were found viable as they developed their colonies on 8.0 per cent water Agar medium after five days Universal Research Publications. All rights reserved INTRODUCTION Cotton is one of the most important commercial crops playing a key role in economic and social affairs of the world. It is mainly cultivated as a fibre as well as oil yielding cash crop. Several fungi found on market seeds used in oil and foods are known to cause considerable damage either directly to those that carry them or to the crops that are raked from such contaminated seed stocks. Generally, we see that the seeds which are used oil and food material and which are easily stored in houses or godowns get infected by fungi after some time. Also the viability of seed is lost due to the effect of fungi found on the surface of the seeds and loses their viability rapidly during storage. For laying down health standards against seed borne diseases of cotton seeds considerable background information is needed with regard to mycoflora associated with such seeds, their role if any, on the disease outbreaks and the nature and extent of damage they cause (Bootmeley et al and 1952, Lalithkumari et al. 1971a, Bilgrami et al. 1976, Singh and Prasad 1977, and Goulart 2007). Therefore, due to economic importance in view of Indian scenario the following cotton seeds have been selected for the study of seed mycoflora and other investigations. MATERIAL AND METHODS- This method was used to detect the external mycoflora of different varieties of cotton viz. Gossypium arboreum, L. G. barbadense, L., G. herbaceum and G. hirsutum, L. seeds. Fifty randomly selected seeds from each sample were divided into two groups, each of which was suspended in 10.0 ml. of sterilized water in conical flasks separately. These flasks were shaken by hand for ten minutes. After shaking equal volume of suspension was transferred into two centrifuge tubes, which were kept in centrifuge and rotated at rpm. for ten minutes. The supernatant liquid was decant off from each tube and then sediment from respective tubes was mounted on slides in loctophenol (Johnston and Booth, 1983) and examined under microscope for the fructifications and mycelial fragements. RESULTS AND DISCUSSION The number and types of fungi were isolated from the sediments obtained from the seed washing according to the technique described under material and method, illustrated in Fig.1 and Tables- I to IV. The examination of sediments obtained from the seed washings of different seed samples was done under compound microscope. From the Gossypium arboreum, L. twelve fungal species belonging to nine genera viz. Alternaria alternata, Aspergillus fumigatus, A. niger, Botrytis cinerea, Cunninghamella elegans, Drechslera tetramera, Fusarium equiseti, F. oxysporum, Mucor hiemalis, Penicillium rubrum, Rhizopus nigricans, and Sterile mycelium were isolated. Alternaria alternata fungi were also isolated from the seed samples of Gossypium barbadense, L., Botrytis cinerea was observed from the seeds of Gossypium arboreum, G. barbadense and G. hirsutum, Aspergillus niger was isolated from the seeds of Gossypium barbadense and G. hirsutium while Aspergillus oryzae was isolated from the seeds of Gossypium herbaceum. Alternaria raphani was also isolated from the seeds of Gossypium herbaceum, Curvularia lunata was 21

2 Mahanandi Sanjay HD-123 Lohit VIKA-5 PA-183 AKH-5 G-27 LD-327 RG-8 Fig. 1. Seed washing test of different varieties of Cotton (A) Gossypium arboreum, L. (B) G. barbadense, L. (C) G. herbaceum, L. and (D) G. hirsutum, L. Table I: Distribution of mycoflora observed from the washings of seeds of different varieties of Cotton (Gossypium arboreum, L.) by mounting the sediments on slides at C. S.No. 1 Alternaria alternata Aspergillus fumigatus A. niger Botrytis cinerea Cunninghamella elegans Drechslera tetramera Fusarium equiseti F. oxysporum Mucor hiemalis Penicillium rubrum Rhizopus nigricans Sterile mycelium

3 Vijay Vijalpa Kalyan Sujay G. Cot.-13 G. Cot.-19 Raichur - 15 Raichur - 51 Suyodhar Jayadhar Mahalaxmi Deviraj Nagnath Khandwa Sujata Suvin TNB-7 HB-224 J-205 Pramukh Table II: Distribution of mycoflora observed from the washings of seeds of different varieties of Cotton (Gossypium barbadense, L.) by mounting the sediments on slides at C. S.No. 1 Alternaria alternata A.brassicicola Aspergillus niger Botrytis cinerea Corynespora cassiicala Curvularia lunata Drechslera tetramera Fusarium oxysporum Penicillium rubrum Rhizopus nigricans Sterile mycelium Table III: Distribution of mycoflora observed from the washings of seeds of different varieties of Cotton (Gossypium herbaceum, L.) by mounting the sediments on slides at C. S.No. 1 Alternaria alternata A. raphani Aspergillus nidulans A. oryzae Curvularia lunata Drechslera tetramera Fusarium oxysporum Pencicillium chrysogenum Rhizoctania bataticola Rhizopus nigricans

4 L-389 G.Cot.-12 Purinima Rajat Buri-107 Narmda LH-900 F-840 RST-9 Ganganagar Ageti Table IV: Distribution of mycoflora observed from the washings of seeds of different varieties of Cotton (Gossypium hirsutum, L.) by mounting the sediments on slides at C. S. No. 1 Aspergillus fumigatus A. niger Botrytis cinerea Curvularia lunata Drechslera rostratum Fusarium oxysporum F.udum Penicillium citrinum Rhizoctonia bataticola Rhizoctonia solani Rhizopus nigricans Sclerotium rolfsii Sterile mycelium commonly observed from the seeds of Gossypium barbadense, G. herbaceum and G. hirsutum, Drechslera tetramera was observed in Gossypium barbadense and Gossypium hirsutum seeds while Drechslera rostrata was observed in G. hirsutum, Fusarium oxysporum was isolated universally from Gossypium barbadense, G. herbaceum and G. hirsutum seeds. The other species of Fusarium, Fusarium udum was observed in the seeds of Gossypium hirsutum and G. herbaceum seeds also yielded Penicillium chrysogenum and the other species Penicillium citrinum and Penicillium rubrum were observed from the seeds of Gossypium hirsutum and G. barbadense, Aspergillus niger was observed on Gossypium barbadense and G. hirsutum seeds, Aspergillus oryzae was recorded on Gossypium herbaceum seeds while Aspergillus nidulans on Gossypium herbaceum seeds and Aspergillus fumigatus on G. hirsutum seeds. Of the various fungi isolated from the seed samples, Alternaria brassicicola and Fusarium oxysporum were predominant and observed in largest numbers with well developed excellent growth in all the seed samples except in the seed samples of Gossypium hirsutum. Aspergillus niger and Rhizopus nigricans were recorded next in prevalence, with fair fungal growth and good number of fungal colonies but fewer infected seeds were recorded in Gossypium arboreum for Rhizopus nigricans. In viability test 75.0 to 90.0 per cent spores of Alternaria brassicicola, 60.0 per cent to 75.0 percent spores of Aspergillus niger and 80.0 to 85 per cent spores of Fusarium oxysporum were found viable as they developed their colonies on 8.0 per cent water Agar medium after five days of streaking of suspension according to the method suggested in material and method REFERENCES- 1. Bilgrami, K.S., Prasad, T., Jamaluddin, Roy, A. K. (1976). Studies on the deterioration of some pulses by fungi. Indian Phytopath. 29 : Bootmeley, R.A.; C.M. Christenson and W.F. Geddes (1950). Grain storage studies. The influence of various temperature, humidity and oxygen concentration. On mould growth and biological changes in stored yellow Corn. Cereal. Chem.; 27: Goulart, A. C. P. (2007). Susuptibility of Cotton Cultivars to Rhizoctonla solani and benifits of fungicides seed treatment. Summa Phyto Pathologica; 33(3); Johnston and Booth, (1983).A role of fungi in deterioration of grain in storage preservation of grains in storage. F.A.O. Agric. Stud; 2: Lalith Kumari, D.L.; P. Vidyasekaran; C.V. Govindaswamy and Sobita Duraiswamy (1971). Reduction in oil content of castor seeds due to storage fungi. Curr. Sci; 40 (10) :

5 6. Singh, B.K. and T. Prasad (1977). Effect of seed borne fungi on the physiological properties of Sunflower oil. Phytopathologischezit Schriff; 9(4): Source of support: Nil; Conflict of interest: None declared 25