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Subject: Plant Pathology × Author: KAU × End date: 1989 ×
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Now showing 1 - 9 of 73
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    ThesisItemOpen Access
    Deterioration of oil cake by fungi
    (Department of Plant Pathology, College of Agriculture, Vellayani, 1989) Naseema, A; KAU; Wilson, K I
    Fungi causing deterioration of coconut, groundnut and sesamum oil cakes were studied. ficremonium implicatum, Asperdllus aculeatus, A. flavus, A. fumigatus, A. nlaer, A. terreus, A. versicolor, Bipolaris hawaiiensis, Curvularia clavata, Monascus ruber, Penicillium aurantioqriseum, P. Pinophilum, Pestalotiopsis palmarum, Rhizomucor £usillus and Ehizopus stolonifer were obtained from coconut oil cake. Aspergillus flavus, A. niaer, A. terreus, A. versicolor, Gliocladium sp. Penicillium pinophilum, RhizoEUS or^zae and Rhizopus stolonifer were noticed in groundnut and Aspergillus candidus, A. flavus, A. fumigatus, A. nlaer, A. tamarii, A. terreus, Curvularia clavata, Eurotium. chevalieri, F"sarium pallidoroseum, Monascus ruber, Fenicilliuiu pinophilum, Pestalotiopsls palmarum and Rhizopus or^zae in sesamum oil cake. Of these, Acremonium implicatum, Aspergillus aculeatus, A. caeslellus, A. .f"-igatus, Bipolaris hawaiiensis, Curvularia clavata, Monascus ru^, Penicillium anrantlogriseum, P. pinophilum, Pestalotiopsls palmarum and Rhizomucor pusillus from coconut oil cake, Aspergillus versicolor, Gliocladium sp., Penicillium pinophilum, Rhizopus oryzae and R. stolonifer from groundnut and Aspergillus candidus, A. fumigatus, A. tamarli, A. terreus, Curvularia clavata, Eurotium chevalieri, Fusarium pallidoroseum,Monascus ruber, Penicillium pinophilum, Pestalotiopsis palmarum and Rhizopus oryzae from sesamum oil cake have not been reported earlier. * Aspergillus flavus and A. niger were isolated from all the samples of groundnut and sesamum oil cakes. In coconut oil cake, these two fungi were present in 88.89 and 77.78 per cent of the samples. A. terreus was isolated from 66.67 per cent of groundnut and 55. 56 per cent of coconut and sesamum oil cake samples. Penicillium pinophilum was obtained from 66.67 per cent of groundnut, 44.44 per cent of sesamum and 27.78 per cent of coconut oil cake samples. Wide variation was noticed in the population of fungi present in the oil cakes collected from different regions during different periods of the year. Oil cakes collected during June-July had the highest population, of fungi. The central and the northern regions recorded higher population of fungi than the southern region. Positive and significant correlation could be obtained between weather parameters and population of fungi in different oil cakes. Maximum correlation was noticed in relation to total rainfall. Qood mycelial growth of fungi was obtained in all the oil cakes incubated at 27, 29 and 32°C. Maximum mycelial growth was noticed at 100 per cent relative humidity. This was followed by 96.1 per cent and 92.9 per cent in the descending order. The oil content of the oil cakes was considerably reduced due to the growth of all the fungi tested individually and in combination. Maximum reduction v/as noticed due to the growth of Pestalotiopsis palmarum in coconut oil cake, Rhizopus stolonifer in groundnut and Fusarium pallidorosem in sesamum oil cake. In the case of combinations, Aspergillus flavus, A. niger and Penicillium pinophilum together caused maximum reduction in oil content of coconut oil cake. In groundnut, combined growth of A. flavus, A. niger and A. terreus caused maximum reduction in oil whereas, A. niger and P. pinophilum together effected maximum reduction of oil in sesamum oil cake. Oil cakes inoculated with different fungi showed considerable reduction in total carbohydrates, crude protein, free amino nitrogen, crude fibre and ash to the extent of 6.11 to 76.95 , 4 . 28 to 68.03, 14.91 to 92.52, 1.25 to 92.55 and 0.17 to 65.16 per cent respectively. In the case of mineral nutrients like phosphorus, potassium, magnesium. calcium, copper and iron reduction ranging from 15.07 to 75.54, 23.13 to 94.41, 10.89 to 63.37, 28.78 to 90.20, 52.52 to 97.12 and 0.32 to 60.77 per cent respectively was noticed. Fourteen out of 2 0 isolates of Aspergillus flavus produced aflatoxins B^, and G2 in culture medium with maximum quantities being 1210, 1040 and 151 ppb respectively by the isolates from coconut oil cake. Eight out of 19 isolates of A. niger elaborated upto 222 ppb by the isolate from sesamum oil cake. When grown on the respective host material, A. flavus isolates from coconut oil cake produced maximum quantity of B^^, B^ and being 1517, 1092 and 272 ppb respectively. A. niger isolate from coconut oil cake produced B^^ upto 419 ppb. oil cakes treated with calcium propionate (0.6 per cent, w/w) were free from fungus growth throughout the period (180 days) of observation and showed minimum number of fungal propagules whereas, those kept as control had higher population of fungi than the treated ones, at all period.of observation. Oil cakes stored in polythene lined gunny bags had the least population of fungi, whereas those stored in ordinary gunny bag had very high population of fungi. These results revealed that fungal deterioration and spoilage of oil cakes could be prevented or reduced to the minimum by treatment with 0.6 per cent calcium propionate- and by using polythene lined gunny bags for storage arid transport.
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    ThesisItemOpen Access
    Studies on the pathogenicity and physiology of Cornespora cassiicola (Berk & Curt.) Wei.
    (Division of plant Pathology ,Agricultural College and Research Institute ,Vellayani, Trivandrum, 1970) George, P V; KAU; Paily, P V
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    ThesisItemOpen Access
    Studies on the production of toxic metabolites by Trichoconis padwickii ganguly in culture filtrate
    (Division of plant Pathology ,Agricultural College and Research Institute ,Vellayani, Trivandrum, 1969) Jayachandran Nair, K; KAU; Sam Raj, J
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    ThesisItemOpen Access
    Effects of collar mot and ring-barking on the Rhizosphere microflora and certain chemical constituents of sword bean plants
    (Division of plant Pathology ,Agricultural College and Research Institute ,Vellayani, Trivandrum, 1968) Kanakambaran, P N; KAU; Sam Raj, J
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    ThesisItemOpen Access
    Study of bacterial leaf spot of betel vine- biochemical changes and control
    (Department of Plant Pathology, College of Agriculture, Vellayani, 1986) Koshi, Abraham; KAU; James, Mathew
    The bacterial leaf spot is one of the most serious diseases of betel vine in Kerala. The bacterium is one of the most serious disease of betal vine. Confidering the seriouness of the disease , studies were undertaken on the different aspects of the disease and to find out a suitable control /management practice.
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    ThesisItemOpen Access
    Air spora over rice crop with special reference to Piricularia oryzae Cav.
    (Division of plant Pathology ,Agricultural College and Research Institute ,Vellayani, Trivandrum, 1967) Maheswari Amma, S; KAU; Sam Raj, J
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    ThesisItemOpen Access
    Mosaic disease of Dolichos bifforus L., transmission , host range and effect of the virus on the host
    (Division of plant Pathology ,Agricultural College and Research Institute ,Vellayani, Trivandrum, 1967) Sukumara Dev, V P; KAU; Sam Raj, J
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    ThesisItemOpen Access
    Studies on certain chemical constituents of banana leaves in relation to incidence of leaf spot diseases. A note on the fungi occurring on banana
    (Division of Plant Pathology ,Agricultural College and Research Institute ,Vellayani, Trivandrum, 1966) Chandrasekharan Nair, M K; KAU; Sam Raj, J
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    ThesisItemOpen Access
    Studies on the helminthosporium Disease of rice detection of mycelium of the fungus in different tissues of the seed obervations on a saltant of Helminthosporium oryzae.
    (Division of plant Pathology ,Agricultural College and Research Institute ,Vellayani, Trivandrum, 1965) Krishnan Kutty Nair, M R; KAU; Sam Raj, J