Thumbnail Image

Kerala Agricultural University, Thrissur

The history of agricultural education in Kerala can be traced back to the year 1896 when a scheme was evolved in the erstwhile Travancore State to train a few young men in scientific agriculture at the Demonstration Farm, Karamana, Thiruvananthapuram, presently, the Cropping Systems Research Centre under Kerala Agricultural University. Agriculture was introduced as an optional subject in the middle school classes in the State in 1922 when an Agricultural Middle School was started at Aluva, Ernakulam District. The popularity and usefulness of this school led to the starting of similar institutions at Kottarakkara and Konni in 1928 and 1931 respectively. Agriculture was later introduced as an optional subject for Intermediate Course in 1953. In 1955, the erstwhile Government of Travancore-Cochin started the Agricultural College and Research Institute at Vellayani, Thiruvananthapuram and the College of Veterinary and Animal Sciences at Mannuthy, Thrissur for imparting higher education in agricultural and veterinary sciences, respectively. These institutions were brought under the direct administrative control of the Department of Agriculture and the Department of Animal Husbandry, respectively. With the formation of Kerala State in 1956, these two colleges were affiliated to the University of Kerala. The post-graduate programmes leading to M.Sc. (Ag), M.V.Sc. and Ph.D. degrees were started in 1961, 1962 and 1965 respectively. On the recommendation of the Second National Education Commission (1964-66) headed by Dr. D.S. Kothari, the then Chairman of the University Grants Commission, one Agricultural University in each State was established. The State Agricultural Universities (SAUs) were established in India as an integral part of the National Agricultural Research System to give the much needed impetus to Agriculture Education and Research in the Country. As a result the Kerala Agricultural University (KAU) was established on 24th February 1971 by virtue of the Act 33 of 1971 and started functioning on 1st February 1972. The Kerala Agricultural University is the 15th in the series of the SAUs. In accordance with the provisions of KAU Act of 1971, the Agricultural College and Research Institute at Vellayani, and the College of Veterinary and Animal Sciences, Mannuthy, were brought under the Kerala Agricultural University. In addition, twenty one agricultural and animal husbandry research stations were also transferred to the KAU for taking up research and extension programmes on various crops, animals, birds, etc. During 2011, Kerala Agricultural University was trifurcated into Kerala Veterinary and Animal Sciences University (KVASU), Kerala University of Fisheries and Ocean Studies (KUFOS) and Kerala Agricultural University (KAU). Now the University has seven colleges (four Agriculture, one Agricultural Engineering, one Forestry, one Co-operation Banking & Management), six RARSs, seven KVKs, 15 Research Stations and 16 Research and Extension Units under the faculties of Agriculture, Agricultural Engineering and Forestry. In addition, one Academy on Climate Change Adaptation and one Institute of Agricultural Technology offering M.Sc. (Integrated) Climate Change Adaptation and Diploma in Agricultural Sciences respectively are also functioning in Kerala Agricultural University.

Browse

1985 - 198927
Reset filters
Subject: Plant Pathology × Author: KAU × End date: 1989 × Start date: 1985 × Type: Thesis ×
Reset filters

Search Results

Now showing 1 - 9 of 27
  • Thumbnail Image
    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.
  • Thumbnail Image
    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.
  • Thumbnail Image
    ThesisItemOpen Access
    Symbiosis of rhizobium and VA mycorrhiza in subabul
    (Department of Plant Pathology, College of Agriculture, Vellayani, 1989) Rajendran Pillai, M V; KAU; Sasi Kumar Nair
    A survey was conducted at 17 locations in four districts of Kerala for natural nodulation and VA mycorrhizal infection in subabul. The survey revealed that natural nodulation and VA mycorrhizal infection were poor compared to inoculated plants. When all the 17 isolates of rhizobia and four cultures of VA mycorrhizal fungus were tested for effectiveness, the rhizobial isolate R8 and V AM fungus M2 were emerged as most efficient rhizobial and mycorrhizal cultures respectively. An in vitro study conducted revealed that in an acid PH of 6, the rhizobial isolate R8 survived better than other cultures. At pH 8, growth of another isolate R5 was found maximum. However, in an in vivo study, there was not much significance for the soil pH ranging from 6 to 7.1 in influencing various biometric parameters of subabul. In both the pH of 6 and 7.1, the performance of rhizobial isolate R5 and mycorrhizal culture M2 was best. Serological studies revealed that the exotic strains R18 R20 and and isolate from Mimosa indica had serological similarities with the best selected local isolate R8. Fine structure studies of nodules clearly showed the morphological differences between the uninfected nodular tissues and the infected central nodular tissue. The rhizobial infection transformed the normal cells into irregularly shaped cells within which numerous rhizobial cells were visible. In another observation, it was found that subabul plants starts to form nodules only from 15 days of sowing. There- after, the nodule number increased steadily attaining the peak at 70 days of growth and then remained more or less steady. Among various methods of inoculation of the microsymbionts tested, inoculation of both the microsymbionts at the time of sowing in polybag was found good for the better establishment of the plants in the field. In a field study, it was found that inoculation of the local isolate of Rhizobium R8 and mycorrhizal fungus M2 had great influence in increasing all the growth parameters. Standard mycorrhizal culture and local isolate performed equally well. Maximum forage yield was obtained when plants were inoculated with the selected local rhizobial isolate R8 and mycorrhizal fungus M2. Maximum mycorrhizal infection was also seen in the same treatment. Dual inoculation also had significant influence in increasing the leaf protein content. An important observation was that both rhizobial and mycorrhizal inoculation reduced the mimosine content of leaves. However, fertilizer nitrogen increased mimosine content. In short, dual inoculation by Rhizobium and VA mycorrhiza was found necessary for better establishment, growth and low mimosine content of subabul.
  • Thumbnail Image
    ThesisItemOpen Access
    Antibiotic producing and antagonistic microorganisms in the forest soils of Kerala
    (Department of Plant Pathology, College of Horticulture, Vellanikkara, 1988) Vinod, P B; KAU; Sukumara Varma, A
    The antibiotic producing and antagonistic fungi, actinomycetes and bacteria in the evergreen forest soils of Ladysmith forest of Thariyode in Wynad, and Cheriyakanom forest of Thekkadi in Idukki districts of Kerala State were studied. The phanerogamic flore around the sites of soil sample collection in both localities were identified. The total microbial population was studied in relation to the depth of soil. The microbial population was maximum in the top layer and decreased with increase in depth of soil. The total microbial population was higher in Idukki and in both districts, population of bacteria was maximum followed by actinomycetes and fungi. A diversified group of fungi consisting, Mucor, Syncephalastrum, Trichoderma, Microascus, Cunningphamella, Absidia, Aspergillus, Penicillium, Talaromyces, Paecelomyces and Fusarium was present. Three types of actinomycetes viz. Streptomyces sp. with straight sporophores, flexuous sporophores and fascicled sporophores were present while four types of bacteria viz., B. subtilis. Bacillus sp. identical to B. subtilis, Bacillus sp. with small cell and fast growth in NA and Bacillus sp. with small cell and slow growth in NA were present. Antagonistic properties of the isolated were studied with the test organisms Pythium myriotylum, Phytophthora palmivora and Rhizoctonia soleni. Mucor sp. and Cunninchamella elegans showed intermingling and overgrowth with all the test organisms while Absidia corymbefera, Syncephalastrum racemosum, Aspergillus meleus, A. tarreus, Microascus cinereus and Fusarium oxysporum showed this character with P. myriotylum and P. palmivora. Intermingling and overgrowth character was observed in Paecelomyces lilacinus with P. palmivora and R. solani whereas A. versicolor and three species of streptomyces showed this character only with P. palmivora. Mutual inhibition on contact was exhibited by Talaromyces wortmannii with all the three test organisms, while A. versicolor and Streptomyces spp. with flexuous sporophores and fascicled sporophores showed this character with P. myriotylum and R. solani. This character was observed in case of A. corymbefera, S. racemosum, A. meleus, M. cinereus, F. oxysporum and Streptomyces sp. with straigtht sporophores, with R. solani while P. lilacinus showed this with P. myrootylum. Mutual inhibition at a distance was shown by Penicillium citrinum, P. simplicissimum, B. subtilis and the other three Bacillus spp. when tested with P. palmivora and R. solani, but A. terreus showed this reaction only with R. solani. Inhibition at a distance and disintegration of test organism was shown by A. niger with P. myriotylum and R. solani while P. citrinum and P. simplicissimum showed this character only with P. myriotylum. All the three spp. of Trichoderma showed die – back and disintegration of all the three test organisms, while A. niger showed this character only with P. palmivora and A. sydowii showed this character with R. solani only. streptomyces sp. with straight sporophores, B. subtilis and the other three Bacillus spp. showed this character with P. myriotylum alone. Inhibitory properties of antagonists using cell free culture filtrates were estimated and found that A. niger inhibited 100 per cent growth of all the three test organisms while P. citrinum, P. simpliciccimum and B. subtilis showed 100 per cent inhibition of P. myriotylum and a range of 67-87 per cent in case of P. palmovora and R. solani. A. terreus did not inhibit P. myriotylum and P. palmivora, but inhibites 78 per cent of R. solani. All the three Trichoderma spp. moderately inhibited all the three test organisms (13-26 per cent) while A. sydowii showed 20 per cent inhibition of R. solani only. Antibiotic property of the antagonists was determined and P. citrinum exhibited maximum, equivalent to 325 ppm tetracycline followed by Streptomyces with straight sporophores having 250 ppm. T. longibracheatum, P. simplicissimum and A. versicolor recovered antibiotic property equivalent to 150 ppm tetracycline hydrochloride while the other isolates had < 100 ppm equivalence of tetracycline hydrochloride.
  • Thumbnail Image
    ThesisItemOpen Access
    Management of sheath blight disease of rice in relation to the population of the pathogen in soil
    (Department of Plant Pathology, College of Horticulture, Vellanikkara, 1987) Shaji, Alexander; KAU; Rajan, K M
    Laboratory, pot and field experiments were carried out to study the role of various physical, chemical and biological factors on the management of sheath blight disease of rice caused by Rhizoctonia solani Kuhn. (Thanatephorus Cucumerlis (Frank) Donk). Populations of total fungi, bacteria and actinomycetes in soil were enumerated at different stages of growth of the crop in order to assess their role in reducing the intensity and incidence of sheath blight disease. Results of the investigation revealed that the pathogen can be managed by deeper ploughing followed by submergence of the soil for a minimum period of two months. Amendments like glyricidia leaves, rice husk, lime and non edible oil cakes of marotti, neem and punna were useful in reducing the severity and spread of the disease. Fungicides like carbendazim and ediphenphos and the herbicide benthiocarb were also efficient in managing the disease. Rotation of rice with crops like tapioca, banana and brinjal was also useful. It was seen that amendments stimulated the population of saprophytes like Trichoderma viride in soil which are antagonistic to R. solani resulting in a subsequent reduction in population of the pathogen. In spite of the reduction in severity and spread of the disease, grain and straw yields were not enhanced by the treatments. More elaborate field trials are to be undertaken before landing on any ultimate conclusion regarding the use of these practices as tools for disease management.
  • Thumbnail Image
    ThesisItemOpen Access
    Transmission, properties and hostrance of snake gourd mosaic virus
    (Department of Plant Pathology, College of Agriculture, Vellayani, 1989) Raghunadhan, D; KAU; Rajagopalan B
    Snake gourd mosaic virus disease commonly occurring in Kerala was investigated. The symptoms appeared as typical mosaic mottling with dark green and light green patches. The leaves were much reduced in size, variously crinkled and deformed. Diseased plants were severely stunted and produced only a few flowers and fruits. Transmission studies showed that the virus could be transmitted through mechanical means, grafting and by aphid vectors. The virus was found to be transmitted by the aphids, Aphis gossypii Glov., Aphis malvae Koch. and Aphis craccivora Koch. Among the three species of aphids, A. gossypii was found to be the most efficient vector. Investigations on the physical properties of the virus revealed that the virus had a thermal inactivation point between 70-750C, Dilution end point between 1:10000-1:50000, longevity in vitro between 96-120 h at room temperature (28-300C), and between 144-168 h at 100C. The minimum acquisition feeding and inoculation feeding period were found to be 30 s and 1 min respectively. But the percentage of transmission was maximum when an acquisition feeding of 20 min and inoculation feeding of 1 h were given. Influence of starvation before acquisition and inoculation feeding proved that pre-acquisition starvation for 1 h produced maximum infection but post-acquisition starvation decreased the per cent infection. The vector was found to retain the virus for 1 ½ h. A single aphid could transmit the virus to healthy test plants, but maximum percentage of transmission was obtained with 10 aphids. Host range studies showed that the virus was restricted to the members of the family chenopodiaceae, compositae, cucurbitaceae and solanaceae. Serological studies showed that snake gourd mosaic virus is related to cucumber mosaic virus and pumpkin mosaic virus. Varietal screening trial with seven varieties of snake gourd revealed that all the varieties were susceptible to snake gourd mosaic virus infection. Studies on estimation of loss revealed that early infection reduced significantly the length of vine, number of leaves, number of flowers, number of fruits and yield, whereas late infection did not produce significant effect, on both the varieties tested. There was significant reduction on leaf area and internodal length on plants inoculated at all stages of growth.
  • Thumbnail Image
    ThesisItemOpen Access
    Varietal variation for nodulation by Rhizobium in Greengram
    (Department of Plant Pathology, College of Agriculture, Vellayani, 1989) Padmanabhan Nair, V; KAU; Sasikumar Nair
    The present investigation on varietal variation for nodulation by Rhizobium in greengram was conducted at College of Agriculture, Vellayani, Trivandrum. The field trial for host varietal specificity was done at C. S. R. C Karamana of Kerala Agricultural University and in a farmer's plot at Pattom, Trivandrum. Rhizobium capable of nodulation in greengram was isolated from 10 out of 14 different soil samples collected from Alleppey, Quilon and Trivandrum Districts. The ten isolates of Rhizobium obtained initially were screened for their nodulation efficiency under aseptic pot culture conditions by using the greengram variety C0-3. In this screening it was found that the increase was maximum in R5 treatment where 188.30 nodules were formed per plant when compared to only 8.33 in the uninoculated control. The fresh and dry weights of nodules formed 455 and 119.33 mg respectively were also maximum in the R5 treatment. A significant increase in root length was obtained only in two of the above treatments R6 and R9. The Rhizobium culture R5 isolated from C.S.R.C. Karamana, Trivandrum was found superior to all other local isolates of rhizobia. Besides the required minimum increase in dry weight of plants from Rhizobium inoculation, 50 per cent increase in dry mass over uninoculated control (as per the Indian Standard Institution Specifications for Rhizobium inoculants is 0268-1976) was obtained only with this isolate of Rhizobium.
  • Thumbnail Image
    ThesisItemOpen Access
    Studies on the seed borne diseases of rice in Kuttanadu
    (Department of Plant Pathology, College of Agriculture, Vellayani, 1986) Jose Joseph; KAU; Susamma Philip
    Several fungi were isolated from the seeds of twelve varieties/cultivars of rice collected from different localities of Kuttanadu, the major rice growing tract of Kerala. Fungi were encountered extrenally as well as internally. Among the externally seed borne fungi, Aspergillus flavus was the most common with its occurrence on nine varieties followed by Bipolaris oryzae and Curvuleria lunata. Other fungi included Rhizopus stolonifer, Chaetomium gracile, Syncephalestrum racemosum, Fusarium moniliforms, Trichoderma virde, Sarocladium oryzae. Aspergillus niger, Alternaria padwickii, Fusarium gramineazum, Piricularia oryzae, A. fumigatus, A. quadrilineatus, Nigrospora oryzae and Penicillium spp. Among the varieties Jaya was found to harbour the maximum fungal population. The germination percentage was not found to be affected due to seed inoculationwith the predominant fungi viz. A. flavus, A. padwickii, B. oryzae, C. lunata and S. oryzae.
  • Thumbnail Image
    ThesisItemOpen Access
    Epidemiology and control of sheath rot disease of rice
    (Department of Plant Pathology, College of Agriculture, Vellayani, 1986) Krishnakumaran Nair, B; KAU; Chandrasekharan Nair, M
    Studies on symptomatology, epidemiology and control aspects of sheath rot disease of rice caused by Serocladium oryzae Cams & Hawksworth (= Acrocylindrium oryzae Saw.) were done in detail. The disease initiated as purplish-brown oblong lesions on the sheath of the flag leaf. At maturity lesions enlarged in size with grey -white centres and often covered the entire flag leaf sheath. Panicle often did not emerge but choked inside the affected sheaf itself. Artificial inoculation studies showed that under sufficient humid conditions the pathogen took an average five to eight days for initiation and 15 to 20 days for the complete development of the disease in rice plants. The pathogen was isolated from four naturally infected rice varieties, collected from three different culture (isolates viz., S1, S2, S3, S4, S5, S6 & S7) were selected based mainly on symptomatological variations and their comperative morphological characters were studied in detail. No appreciable differences were noticed in the morphological characters between isolates.