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

2000 - 200219
Reset filters
Subject: Plant Pathology × Author: KAU × End date: 2002 × Start date: 2000 ×
Reset filters

Search Results

Now showing 1 - 9 of 19
  • Thumbnail Image
    ThesisItemOpen Access
    Management of bacterial blight of anthurium (anthurium andreanum linden) using botanicals
    (Department of Plant Pathology, College of Agriculture, Vellayani, 2002) Sabitha, S R; KAU; Mary, C A
    Anthurium (Anthurium andreanum Linden) suffers from a serIOUS disease viz., bacterial blight incited by Xanthomonas axonopodis pv. diefJenbachiae (McCulloch and Pirone) Vauterin et al. A survey was conducted in Thiruvananthapuram district and information on disease intensity and varietal reaction of the disease was studied from randomly selected thirty anthurium gardens. Plants with disease infection upto 50 per cent was noticed in most of the gardens. Generally pink varieties exhibited tolerance while red varieties were susceptible. Both foliar and systemic symptoms were observed. The bacterium was a gram negative, motile, short rod. Potato Sucrose Agar was the best solid medium for growth of the bacterium. Morphological, physiological and biochemical characters of the ten isolates were compared and some characters like nature and rate of growth, virulence and hydrolysis of starch were found varying. Aglaonema sp., Alocasia sanderiana, Anthurium ornatum, Colocasia esculenta, Dieffenbachia spp., Philodendron spp., Syngonium sp. and Xanthosoma sagittaefolium of Araceae family and ornamental plants like Orchid spp., Dracaena spp. Heliconia sp., Sterilitzia reginae and Maranta arundinaceae were hosts of the pathogen. Among the fifteen botanicals tested under in vitro conditions crude extract and 2 : 1 dilution of Allium sativum and Tagetes erecta, crude and two per cent concentration of neem cake extract and one and two per cent neem oil and coconut oil were 'effective in inhibiting the growth of the pathogen. The relative efficacy of five ecofriendly management practices viz., application of A. sativum, T. erecta, neem oil, coconut oil and neem cake extract, at two levels and 100 ppm streptocycline were tested on seven month old tissue culture plants. Pre and post inoculation sprayings with crude extract of neem cake and T. erecta reduced the disease by 85 per cent. When the same spraying schedule with these two botanicals and 100 ppm streptocycline was given on flowering plants, crude extract of neem cake was the most effective followed by crude extract of T. erecta. The effect of streptocycline 100 ppm was on par with T. erecta. The study thus indicates that botanicals could be used as a substitute for antibiotics in the management of bacterial blight of anthurium.
  • Thumbnail Image
    ThesisItemOpen Access
    Exploitation of hypovirulence in Rhizoctonia solani kuhn for Management of sheath blight in rice
    (Department of Plant Pathology, College of Agriculture, Vellayani, 2001) Ranjit, A; KAU; Girija, A K
    A study was conducted at Department of Plant Pathology, College of Agriculture, Vellayani to explore the variability in Rhizoctonia so/ani with a view to detect hypoviruient strains of the fungus, and evaluate the efficacy of these isolates in management of sheath blight disease of rice. Six hypovirulent isolates were selected after screerung 28 isolates obtained from different rice growing tracts of Kerala. Screening for hypovirulence was . based on cultural characters like mycelial growth rate and sclerotial production under ill vitro conditions, and pathogenicity tests through cut stalk assay. The hypovirulent isolates were non-sclerotial whereas the virulent isolate produced profuse sclerotia. The hypovirulent isolates produced tan mycelia appressed to the medium In Petri dishes. Antibiosis and hyperparasitism were absent in the interaction between the hypovirulent and virulent isolates in vitro. The character of hypovirulence could not be transmitted from hypovirulent to the virulent isolate. The hypovirulent isolates had no effect on the germination and seedling vigour of rice plants. They did not produce symptoms of sheath blight on susceptible variety. Two of the six hypovirulent isolates selected viz A 13 and GR23 which were binucleate and did not anastomose with the selected virulent isolates, offered the maximum protection to the rice plants from sheath blight. The plants treated with GR23 showed immune reaction to challenge inoculation with virulent isolate, showing no symptom production on challenge inoculation with virulent isolate. The protective effect was found to be higher than that of chemical and biological control treatments. The phenol oxidase activity in the plants treated with the hypovirulent isolates was found to be significantly higher than that of the plants treated with virulent isolate while the peroxidase activity was higher in the plants treated with virulent isolate. Among the different carrier materials tested for hypovirulent Rrsolani rice bran was found to be good for long term storage and coirpith was found to be a cheap indigenous material for its mass multiplication.
  • Thumbnail Image
    ThesisItemOpen Access
    Influence of VAM inoculation on nutrient uptake, growth, yield and bacterial wilt incidence in tomato (Lycopersicon esculentum Mill.)
    (Department of Plant Pathology, College of Horticulture, Vellanikkara, 2002) Raji, P; KAU; Sukumara Varma, A
    An investigation on the influence of VAM inoculation on nutrient uptake, growth, yield and bacterial wilt incidence of tomato (Lycopersicon esculentum Mill.) was carried out at the College of Horticulture, Vellanikkara during the period 1996 - 2000. The objectives of the study were to select an efficient VAM fungus for improving nutrient uptake, growth and yield of tomato, to explore the possibility of reducing the use of phosphorus fertilizer by VAM inoculation and also to study its influence on bacterial wilt incidence. The survey conducted revealed the natural occurrence of VAM association in tomato at different locations of Kerala. There was variation in VAM colonization and rihzosphere spore count among the locations. Predominant VAM fungi associated with tomato at the survey locations belonged to the genus Glomus. Out of the fifteen native isolates and four standard cultures, Glomus mosseae, Glomus fasciculatum, Glomus intraradices and Gigaspora margarita, the native isolate collected from Eruthempathi (Palakkad District) was found to be the best in improving nutrient uptake, growth and yield of tomato variety, Sakthi. Inoculation of this isolate resulted in increased root colonization, spore count, shoot and root biomass, root volume and yield. It induced seven days early flowering and increased the ascorbic acid content of the fruit. The uptake of nutrients particularly P, K and Ca was improved by the inoculation of this isolate. The pot culture experiment conducted to study the possibility of reducing phosphorus fertilizer due to VAM inoculation showed the superiority of VAM isolate collected from Eruthempathi in improving growth, P uptake and yield. With the increase in dose of P upto 50 per cent, there was a significant increase in root colonization, fresh weights and dry weights of shoot and root and also the yield. No further increase in these parameters was recorded with the increase in dose of P upto 100 per cent. The plants inoculated with the VAM isolates along with 50 per cent P recorded shoot and root biomass and yield significantly superior to that of these parameters recorded by the plants which received full dose of P alone. The results of the field experiment showed that the plants inoculated with VAM had higher root colonization and rihzosphere spore count compared to uninoculated plants. Irrespective of the form of P used the rihzosphere spore count and VAM colonization were less at higher doses of P compared to lower doses. Among the treatments involving super phosphate, the treatment T9 (VAM + FYM + N + 50% SP + K) was significantly superior in improving root colonization, spore count, fresh weight and dry weight of root, root length, shoot P content and yield compared to the package of practices recommendations (T2 - FYM + N + SP + K). Among the treatments involving mussorie rock phosphate, the treatment Tio (VAM + FYM + N + 75% MP + K) was significantly superior to the present package of practices recommendations in its effects on fresh weight and dry weight of shoot and root, root length, shoot P content and yield. The nutrient status of the soil with respect to P_ and K content was improved by the treatment T9 (VAM + FYM + N + 50% SP + K). No significant change in soil P content was observed by the VAM inoculation along with MP. The treatment Tio (VAM+FYM+75%MP+K) recorded the highest soil K content. The field experiment conducted in the wilt sick field revealed that inoculation of selected VAM fungi could reduce the bacterial wilt incidence. Among the three varieties tested viz., Sakthi, BWR-1 and Pusa Ruby, a significant reduction in bacterial wilt incidence due to inoculation of VAM fungi collected from Eruthempathi was recorded by the variety, Sakthi. The inoculated plants of BWR-1 showed only five per cent reduction in wilt incidence. No reduction in wilt incidence was observed in variety, Pusa Ruby.
  • Thumbnail Image
    ThesisItemOpen Access
    Comparative efficiency of lignocellulolytic fungi for bioconversion of coirpith
    (Department of Plant Pathology, College of Agriculture, Vellayani, 2002) Reeja, R S; KAU; Lulu Das
    Nine lignocellulolytic fungi, of which SIX viz., Pleurotus eous, P. squarrosulus, two strains of Calocybe indica, Schizophyllum commune and Coprinus comatus collected from Thiruvananthapuram district as a part of the study entitled "Comparative efficiency of lignocellulolytic fungi for bioconversion of coirpith" and three from AfCRP Centre on Mushrooms, College of Agriculture, Vellayani were used to find out their ability to decompose coirpith. All these fungi preferred natural media such as Oatmeal Agar and Potato Dextrose Agar, a temperature range of 25 -. 35°C and neutral to acidic pH for their optimum growth. , ' I In vitro studies were conducted to find out the efficient strains. Pre and post composting physico-chemical analysis were carried out. Coirpith was found to be acidic in nature. EC of non retted coirpith was very high. Ability of these fungi in degrading organic carbon, cellulose and lignin thereby narrowing down the C : N ratio and increasing the nutrient status were found out. Field level trials using P. eous, P. squarrosulus, P. sajor-caju, P. florida, C. indica-Z and S. commune revealed that all these fungi could efficiently degrade coirpith, Better degradation of retted and non retted coirpith was observed when they were inoculated with lignocellulolytic fungi for 45 days. Maximum reduction in organic carbon and C : N ratio was brought about by P. eous and S. commune in non retted coirpith. Higher concentration of nitrogen was observed in retted coirpith inoculated with the same fungi. The phosphorus content was maximum m non retted coirpith inoculated with P. eous, C. indica-Z; S. commune and P. squarrosulus. Maximum potassium content was observed In non retted coirpith treated with P. eous and P. sajor-caju. P. eous and P. sajor-caju treated retted coirpith brought about maximum reduction in cellulose, while lignin degradation was maximum for P. sajor-caju and P. eous treated non retted coirpith. P. eous brought about the maximum reduction in weight of retted and non retted coirpith, while maximum volume reductioh was noticed in retted and non retted coirpith inoculated with P. eous and S. commune respectively. The final compost was dark brown in colour with low levels of organic carbon, cellulose, lignin, narrow C : N ratio and with increased nutrient status. The results of the experiment clearly showed that P. eous, P. sajor- caju and S. commune are efficient decomposers of coirpith.
  • Thumbnail Image
    ThesisItemOpen Access
    Evaluation of fluorescent pseudomonads for the management of sheath blight and bacterial blight of rice
    (Department of Plant Pathology, College of Agriculture, Vellayani, 2002) Heera, G; KAU; Kamala, Nayar
    Biological control of major foliar diseases of rice in Kerala viz., sheath blight and bacterial blight using fluorescent pseudomonads was studied. Isolates obtained from the phylloplane were observed to be effective In inhibiting the growth of foliar pathogens. Isolate P 11 was most effective In inhibiting the growth of Rhizoctonia solani inciting sheath blight disease whereas growth of bacterial blight pathogen Xanthomonas oryzae pv oryzae . was suppressed by the isolate P33, under in vitro conditions. P 11 and P33 survived well in the inert material talc used as carrier material in the formulation developed, using these isolates. Seed treatment with talc based formulation of each isolate (P 11 and P33) increased the dry weight of root and shoot of rice seedlings of cultivar Jyothi and TN-l 14 days after sowing. The isolates produced almost equal and detectable amounts of IAA in culture supernatant. Greenhouse studies conducted at the College of Agriculture, Vellayani, indicated that a combination of seed treatment (10g kg" seed), seedling root dipping (1 per cent solution), and foliar spray (1 per cent) with the formulation of PI 1 and P33 effectively suppressed sheath blight and bacterial blight disease respectively and also appreciably increased the biomass yield of treated rice plants. Three foliar sprays starting two days prior to inoculation with the pathogen, during the tillering stage of the crop enhanced the efficacy of seedling root dipping with the biocontrol formulation. Isolates P 11 and P33 were tentatively identified as Pseudomonas aeruginosa and Pseudomonas fluorescens biovar 1 respectively.
  • Thumbnail Image
    ThesisItemOpen Access
    Integrated management of bacterial wilt of tomato caused by Ralstonia solanacearum (Smith) Yabuuchi et al.
    (Department of Plant Pathology, College of Horticulture, Vellanikkara, 2002) Akbar, K I; KAU; Sheela Paul, T
    Bacterial wilt of tomato caused by Ralstonia solanacearum (Smith) Yabuuchi et al. has continued to be a perennial problem due to its complex interaction with soil. Hence a study has been taken up to isolate a potent biocontrol organism and to develop a strategy by integrating the selected control methods so as to have a sustainable eco-friendly tomato production. The pathogenic bacterium R. solanacearum was isolated from four different locations and the characterization studies revealed that the four isolates of the pathogen belong to R. solanacearum race 1 biovars3. The antagonistic bacterium isolated from the central zone was capable of producing abundant bluish green diffusible fluorescent pigment and a non diffusible non fluorescent brown pigment in King's B medium. Based on the physiological and biochemical studies, this bacterium was tentatively identified as Pseudomonas aeruginosa. Seed treatment - with _ antagonistic bacterium facilitates earliness ID germination and better plant VIgOur in both Pusa Ruby and Sakthi varieties compared to other treatments, Data on solarisation studies also showed that solarisation for 30 days has a weak effect in checking the R. solanacearum population. In bioassay studies garlic 10 per cent and the Copper fungicides, Bordeaux mixture 1 per cent and Copper hydroxide 0.15 per cent were sensitive to Risolanacearum but insensitive to P. aeruginosa. In pot culture studies, the seeds of the resistant variety Sakthi treated with beneficial agent, garlic drenching or Bordeaux mixture drenching were found to be superior to all other treatments in reducing the wilt incidence. In the main field, treatment combinations were tried based on the results of pot culture experiments. The rate of increase in wilt incidence was highest in the early stages and at flowering stage. The plants withstand bacterial infection upto flowering stage because of the resistant mechanism present in the variety Sakthi. The result of the study indicated that the bacterial disease of tomato could be effectively managed by integrating indigenous antagonistic activity of P. aeruginosa and selective bactericides like garlic extract or Copper hydroxide 0.15 per cent along with the host resistance of variety Sakthi.
  • Thumbnail Image
    ThesisItemOpen Access
    Biocontrol of anthracnose of black pepper (Piper nigrum L.) caused by Colletotrichum spp. using mycoparasites
    (Department of Plant Pathology, College of Agriculture, Vellayani, 2002) Anoop Sankar; KAU; Santhakumari, P
    An investigation was done for exploiting potential biocontrol agents for the management of anthracnose of black pepper. Survey conducted on the incidence of anthracnose disease in eleven different locations of the state during February - July 2000 revealed that Colletotrichum gloeosporioides was the most common pathogen associated with this disease. Distinct variability in morphological characters and pathogenicity was exhibited by the di"fferent isolates of the pathogen. The most virulent isolate was isolate C6 from Perinthalmanna. The pathogen survived for three months on infected leaves in the soil and upto five months on infected leaves under laboratory conditions. A study was conducted to isolate potential mycoparasites of C. gloeosporioides from the rhizosphere and phyllosphere of both healthy and diseased black pepper plants from the various locations surveyed. Among the fungi isolated, two isolates of Trichoderma harzianum Rifai (T I and T 2) and two isolates of Aspergillus niger van Tieghem (A, and A2) were found to be most effective in' inhibiting C. gloeosporioides in vitro. After mass multiplication, the selected fungal antagonists were formulated in talc, which was found to be the best carrier material for maintaining the viability of the antagonists. The shelf life of the talc based formulations were 150 days and 180 days for the T. harzianum isolates and A. niger isolates respectively. The antagonistic fungi were tested separately under greenhouse conditions by a combination of two methods of application viz., soil application and foliar spray. Greenhouse studies indicated that all the four isolates were equally effective In suppressing the development of the disease in black pepper cuttings. Application of the talc based formulations of the four isolates in the soil @ 109 / kg soil followed by foliar spray with one per cent suspension of the talc based formulations twice at 15 days interval starting from 10 days after pathogen inoculation was very effective in controlling the disease under greenhouse conditions. In general, application of the fungal antagonists promoted the growth of black pepper cuttings. Isolate Al produced maximum shoot length, root length and fresh weight in the treated black pepper cuttings. The results of the study assigned dual roles as biocontrol agents and plant growth promoters for all the four fungal antagonists.
  • Thumbnail Image
    ThesisItemUnknown
    Efficacy of selected biopesticides for the management of sheath blight of rice
    (Department of Plant Pathology, College of Horticulture, Vellanikkara, 2001) Saifunneesa, T K; KAU; Rehumath Niza, T J
    Studies on 'Efficacy of selected biopesticides for the management of sheath blight of rice' was conducted at the College of Horticulture, Kerala Agricultural University, Vellanikkara during 2000-2001. The major objective was to evolve a safer and eco-friendly management practice against sheath blight disease of rice. In vitro evaluation revealed Trichoderma viride and 2B as the best fungal and bacterial antagonists respectively. Fungi such as Aspergillus niger, A. terreus, Penicillium chermesinum, Cunninghamella bertholletiae and bacteria such as 1 B (Clostridium sp.), 4B, 7B (Bacillus sp.), lOB (Sporosarcina sp.), 19B (Bacillus sp.), 28B and Pseudomonas jluorescens showed significant inhibition of Rhizoctonia solani. Initial screening of the botanicals resulted in the selection of Chromolaena odorata, Leucaena leucocephala and Ocimum sanctum as the effective botanicals in the inhibition of R. solani. All these inhibited the formation of sclerotia even at five per cent concentration. Of the neem based formulations, Nimbecidine at 0.75 per cent concentration showed the maximum inhibition of 70.79 per cent and inhibited the sclerotial formation even at 0.5 per cent level. Comparative evaluation of microbial antagonists, botanicals and neem , based formulations were carried out in in vivo for the selection of potential ones to field experiment. In the present study T viride was selected as the best antagonist followed by 12B(Clostridium sp.), 28B, unidentified ascomycetes (20F), Acrophialophora sp., C. bertholletiae, Trichoderma sp. in that order. Among the botanicals C. odorata was the best as corroborated by the CODEX value of 3.56 and was followed by O. sanctum with a CODEX Value of five on 30th day of inoculation. Out of the two neem based formulations, Nimbecidine (azadirachtin 0.03%EC) showed the maximum control on the disease up to 30th day of inoculation (CODEX=1.17-2.29). The botanicals namely C. odorata, O. sanctum and neem based formulation Nimbecidine were found as effective as carbendazim 0.1 per cent. The effect of bioagent T. viride, neem based formulation Nimbccidine as well as botanicals C. odorata, O. sanctum and fungicide carbendazim were tested under natural field condition. To select the most effective schedule, the different combinations of biopesticides for seed, soil and foliar applications were tried. Among the different biopesticides T. viride applied on seed, soil and foliage (T3) showed maximum disease control and was equally effective as carbendazim O.lper cent. Seed treatment cum soil application of T viride (T2) came next in reducing sheath blight infection and has given the highest benefit: cost ratio. Treatment T3 was also economically viable as carbendazim 0.1 per cent. An increase in the activity of phenylalanine ammonia lyase (PAL) was noticed with the foliar spray of T viride, Nimbecidine, C. odorata, and carbendazim.
  • Thumbnail Image
    ThesisItemUnknown
    Molecular characterisation of Ralstonia solanacearum (Smith) Yabuuchi et al causing bacterial wilt in solanaceous vegetables
    (Department of Plant Pathology, College of Horticulture, Vellanikkara, 2001) Deepa, James; KAU; Girija, D
    Bacterial wilt incited by Ralstonia solanacearum is one of the most devastating diseases of solanaceous vegetable crops in Kerala. Crop losses due to the incidence of this disease may go upto 100 per cent. Existence of different strains, races and biovars has been responsible for breaking down of resistance of varieties evolved through breeding programmes. In view of wide variability, a study was undertaken to characterise the isolates of R. solanacearum collected from three different agro climatic zones ofKerala at molecular level. Nine isolates of R. solanacearum collected from three different locations from brinjal, chilli and tomato were used in the study. These were isolated, purified and maintained in sterile distilled water at room temperature. Inoculation techniques were standardised in brinjal, chilli and tomato plants for assessing the virulence and aggressiveness of the isolates. Virulence and aggressiveness of the isolates were studied on respective host plants and found them highly varying. Vellanikkara and Kumarakom isolates could cross inoculate, whereas Ambalavayal isolates did not. The isolates were characterised by various cultural, morphological and biochemical tests and the variability among them was studied. Biovars, III and IlIA and races, 1 and 3 were identified among the isolates. The isolates were resistant to ampicillin and sensitive to chloramphenicol. Plasmid DNA profile of the isolates were studied and no difference was found in the plasmid DNA profile of the nine isolates. Polymorphism among the isolates was studied using RAPD with ten decamer primers. RAPD profiles exhibited great diversity among biovars III and IlIA as well as among race 1 isolates. Race 3 isolates were less polymorphic with certain primers tested. OPF8 yielded a unique band specific to race 3 isolates. Dendrogram obtained from the pooled data of RAPD profiles also showed high genetic similarity between race 3 isolates. Dendrogram obtained from the pooled data of RAPD profiles also showed high genetic similarity between race 3 isolates. Restriction analysis could not characterise the isolates since no banding pattern was obtained with restricted DNA. No hybridization signal was detected after Southern hybridization in RFLP. Curing of plasmid DNA at high temperatures was found unsuccessful. Plasmid profiles of both mucoid and non-mucoid colonies were compared to assess the role of plasmid in EPS production and the plasmid could be observed in both types of colonies. In the latter, a reduction in size of the plasmid was noticed. Thus the study revealed that great diversity existed among strains of R. solanacearum at different locations of Kerala when molecular techniques, especially RAPD was used as a tool.