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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.
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ThesisItem Open Access Biodiversity of the termite (isoptera) fauna in crop environments(Department of Agricultural Entomology, College of Horticulture, Vellanikkara, 2011) Jyothy, Narayanan; KAU; Jim, Thomas (Guide)Termites (Insecta: Isoptera) are eusocial insects living in a highly organised and small to large extent of communities in different ecosystems. A termite colony has morphologically and functionally distinct caste system which includes functional reproductives / ‘royal pair’ of king and queen, sterile soldier and worker castes and the immature stages or nymphs along with other inquiline species of organisms. The present investigation on the ‘Biodiversity of the termite (Isoptera) fauna in crop environments’ was undertaken in a few selected crop environments in the instructional farm area of the College of Horticulture at Vellanikkara during 2010-11. The main objectives of the study were to identify the composition of the termite fauna up to the family/ genus level in mango, cashew, cocoa and coconut crop environments, elucidation of their feeding nature, behaviour, association and their mound forming characteristics and to prepare a primary termite colonisation map in the selected plantation and orchard systems in this tract. A preliminary survey was conducted by transect walk throughout the instructional farm area of the campus to select the termite prone plantation and orchard systems for the study. The soldier castes of termites were sampled from a unit area of 200 sq. m each from different crop environments and kept under preservation. The soldier castes from earthen mounds were collected by a special “Glue trap technique” designed and standardised for the purpose by the author through 20 numbers of encounter samplings per unit area of observation. The soldier castes were identified based on the standard keys (Bose, 1984; Roonwal and Chhotani, 1961 and Sornnuwat et al., 2004) with reference to their characteristics of head capsule, mandibles and pronotum. The diversity pattern of termite genera in different agro ecosystems in Vellanikkara were assessed by using various diversity indices. Based on these information, a preliminary termite colonisation map was prepared by depicting the distribution, spread and colonisation density of the identified termite genera in the selected crop environments. The morphometry of the aerial mounds along with some of the physical properties of the termitarial soils were also determined. The influence of temperature and humidity on the termite colonisation process was also observed. A total of nine termite genera under two families were identified in Vellanikkara. Out of this, seven termite genera viz., Odontotermes, Procapritermes, Dicuspiditermes, Homallotermes, Microtermes, Microcerotermes and Nasutitermes were under the family Termitidae, while, Heterotermes and Coptotermes were coming under the family Rhinotermitidae. Odontotermes was found to be the most dominant genus in all the selected crop environments accounting for about 62.03 per cent of the total genera identified from the Vellanikkara tract. The least present genus was Coptotermes which constituted only 1.27 per cent among all the identified genera. Based on the distribution, spread and colonisation density, a primary termite faunal distribution map was prepared in selected systems. The genera viz., Odontotermes, Microcerotermes, Nasutitermes, Heterotermes and Coptotermes were identified as wood feeders while, Procapritermes, Dicuspiditermes, Homallotermes and Microtermes were observed as soil/ humus feeders. Various diversity indices were worked out for the faunal distribution of the termites in this tract to find out their relative dominance, spread and evenness in its distribution. The genus richness of the termite genera at Vellanikkara tract was found to be 9 and the value of Simpson- Yule diversity Index (D) was found to be 2.44 and that of the Shannon- Weiner Diversity Index (H) was found to be 1.38. The Evenness Index (E) when worked out was found to be 0.63 and the Berger Parker Dominance Index (d) for the genus Odontotermes was found to be 0.62. When different systems were compared, the genus richness was found to be the highest in cashew plantation with a value of 6 while, the mango, cocoa and coconut systems were having a value of 3 only. The D value of 4.65, H value of 1.64 and the E value of 0.92 was found to be highest in cashew plantation, which indicated that the cashew system was supporting maximum generic diversity of the termites with a more evenness in its distribution. The values of these indices were found to be the lowest in cocoa which indicated that the cocoa based systems was having the lowest diversity and very low evenness in the distribution of various genera. The mango and coconut based systems were having intermediate values with these indices. The “d” value indicating the dominance of the particular termite genus viz., Odontotermes was found to be the highest in the cocoa based system with a value of 0.75 and the least in cashew with a value of 0.33. The mean density of the mounds in mango, cashew and cocoa based systems varied only slightly indicating their relative uniform distribution. The mean number of buttresses or young mounds ranged from 5- 7 per mound formation. The mean height of the mounds present in all the three systems showed only very slight variation, but there was difference in the mean basal circumference of the mounds in the three systems. Accordingly, the mean external volume (above ground) of the mounds in cubic centimetres was found to be the highest in cocoa and least in mango based systems. Statistical analysis of the data revealed that there was no significant difference in the relative per cent increase in the external volume of the mounds in cocoa plantation, while, there was significant difference in the change of volume as observed in July’10- Aug’10 and Jan’11- Feb’11 in mango and cashew based systems implicating the degree and period of termite activity within the termitaria. Regarding the physical properties, the soil colour of the mounds and of the adjacent soil during the wet season was found to be dark reddish brown as per the visual comparison through the standard Munsell colour chart. However, the colour of the mound soil and of the adjacent soil during the dry season was found to be brown and dark reddish brown, respectively. Particle size distribution in the soil samples of the termitarial mounds from the three crop environments viz., mango, cashew and cocoa based systems showed no significant difference among them. But within the same crop systems, the clay content of the mound soil was observed to be increasing by 10-12 per cent while, the sand content was decreasing by about 10-15 per cent. There was not much variation in silt content between the mound soil and adjacent soil. However, gravel was found to be totally absent in the mound soil as compared to the adjacent soils. When the temperature and relative humidity were recorded and compared between inside and outside of the mounds, it was found out that both temperature and relative humidity inside the mounds were significantly higher than that of the external environment which prove that the termites have to essentially maintain their homoeostasis with respect to the internal ambience for their survival and other activities irrespective of the external ambience. To conclude, the study reveals that the Vellanikkara tract is diverse in the faunal distribution of termites with nine genera under two families and five subfamilies with a dominant mound dwelling genus viz., Odontotermes in all the crop environments of mango, cashew, cocoa and coconut systems. The identification of the termite genera can very well be undertaken based on head capsule and mandibular characteristics of the soldier caste by collecting them easily by the newly designed method of “glue trap technique” by the author. The termites colonize these systems without any major environmental or resource degradation and thereby their role may be further investigated for the eco restoration and conservation activities.ThesisItem Open Access Bioefficacy and safety evaluation of biorational insecticides for the management of sucking pest complex of chilli (capsicum annuum L. )(Department of Agricultural Entomology, College of Agriculture, Vellayani, 2011) Thania, Sara Varghese; KAU; Thomas, Biju MathewThe efficacy and safety of biorational insecticides used for the management of sucking pest complex of chilli, viz. mites (Polyphagotarsonemus latus Banks), thrips (Scirtothrips dorsalis Hood) and aphids (Aphis gossypii Glover) were tested in laboratory and field conditions. The efficacy of eight new generation insecticides viz., spinosad 75 g a.i. ha-1, spiromesifen 100 g a.i. ha-1 , spirotetramat 60 g a.i. ha-1 , indoxacarb 60 g a.i. ha-1 , imidacloprid 20 g a.i. ha-1, thiamethoxam 40 g a.i. ha-1 , flubendiamide 60 g a.i. ha-1 and acetamiprid 20 g a.i. ha-1 was assessed in comparison with propargite 570 g a.i ha-1 and dimethoate 300 g a.i ha-1 as acaricidal and insecticide check, against three sucking pests of chilli viz, mites, thrips and aphids under laboratory conditions. Based on the laboratory evaluation, acetamiprid, spiromesifen, propargite, spinosad and dimethoate were very effective against chilli mite whereas 100 percent mortality of chilli thrips was obtained in spinosad, spiromesifen, imidacloprid, thiamethoxam, acetamiprid, propargite and dimethoate in leaf disc method. The neonicotinoid insecticides viz, acetamiprid, imidacloprid, thiamethoxam and other insecticides viz, spiromesifen and dimethoate were found effective against chilli aphids. Spiromesifen was found as the safest insecticide to coccinellid and hemerobid grubs. Flubendiamide, spirotetramat and indoxacarb were also found safe to coccinellid grubs and hemerobid grubs, but they were not effective against the pest complex of chilli. Dimethoate was found toxic to coccinellid and hemerobid grubs. Among the neonicotinoid insecticides, acetamiprid and thiamethoxam were safer than imidacloprid. In the safety evaluation against the predatory mite Amblyseius spp, acetamiprid, thiamethoxam, spiromesifen and spirotetramat were safer than other insecticides. In the pot culture study, significantly lower population of chilli mites were recorded in spiromesifen, propargite, imidacloprid, acetamiprid, thiamethoxam and dimethoate sprayed chilli plants. Chilli thrips were not recorded in acetamiprid sprayed chilli plants upto seven days after spraying. When the damage caused due to the feeding injury of mites and thrips were indexed, (Leaf curl Index) lower indices were recorded in spiromesifen and propargite sprayed chilli plants. Among the different chemicals evaluated in field viz, spiromesifen, imidacloprid, acetamiprid thiamethoxam, propargite and dimethoate, ethion and oxy demeton methyl, the mite population was significantly lower in propargite, spiromesifen and acetamiprid treated plots. Acetamiprid treated plots recorded the lowest thrips population and lowest average leaf curl index (LCI) was recorded in spiromesifen and propargite treated plants. Spiromesifen and propargite treated plots harboured maximum numbers of natural enemies, where as among the neonicotinoids, acetamiprid and thiamethoxam were comparatively safer than imidacloprid. The yield of chilli was more in spiromesifen treated plants followed by acetamiprid sprayed chilli plants. Considering the waiting period of different insecticides worked out in the present investigation, acetamiprid is having the shortest waiting period of 3.51 days and it is the only insecticide which fits well in to the harvest interval of chilli fruits, whereas the conventional insectides like ethion and dimethoate recorded the maximum waiting period of 27.89 and 13.63 days, respectively. The half-life of acetamiprid, ethion and dimethoate were 2.27, 3.43 and 1.94 days respectively. The insecticide spiromesifen, sprayed on chilli fruits had a waiting period of 7.03 days to reach below the MRL of 0.5 ppm and the time taken for half of the spiromesifen to degrade was 1.71 days. Imidacloprid sprayed on chilli fruits took 2.08 days to degrade its residues to half of the initial deposit and the waiting period was fixed as 6.8 days. Propargite had a waiting period of 5.7 days on chilli fruits and the half life was calculated as 0.63 days. The insecticides selected to study the effect of different processing techniques in removing the insecticide residues on chilli fruits harvested at two hours after spraying and at five days after spraying were spiromesifen, imidacloprid, acetamiprid, propargite, ethion and dimethoate. In the case of spiromesifen, maximum residue removal (90.03%) occurred when the fruits were dipped in tamarind 2% solution followed by washing in water. For imidacloprid, all the treatments were very effective in removing residues, more than eighty percent of the residues were removed in all the treatments which justify its high polarity and the maximum removal was recorded when the fruits were dipped in 2% solution of tamarind (96.83%) followed by washing in water. In the case of acetamiprid, mere water wash removed 97.69% of the residues where as in the case of propargite, maximum removal of residues was obtained by dipping in 2% solution of tamarind (96.69%) for twenty minutes followed by washing in water. The extent of residue removal in the OP insecticides viz, ethion and dimethoate was less when compared to other new generation insecticides. In the case of ethion sprayed chilli fruits, maximum residues were removed when the fruits were dipped in 2% solution of lemon juice (83.13%) followed by washing in water. For dimethoate sprayed chilli fruits, maximum removal of residues occurred when the fruits were dipped in 2% solution of tamarind (53.98%). Out of six insecticides studied, dipping insecticide treated chilli fruits in 2% tamarind solution for twenty minutes followed by washing in water removed maximum amount of residues in the case of spiromesifen, imidacloprid, propargite and dimethoate. In the case of ethion also, tamarind treatment removed fairly good amount (60.88%) of residues. Owing to this majority, tamarind can be recommended as a good option for removing insecticide residues from fruits and vegetables.ThesisItem Open Access Potency of bioinsecticides against the cowpea bruchid, Callosobruchus maculatus (F.) (Coleoptera:Cysomelidae) in storage(Department of Agricultural Entomology, College of Horticulture, Vellanikkara, 2011) Amritha Kumari, S; KAU; Sosamma, JacobThe present study entitled ‘Potency of bioinsecticides against cowpea bruchid, Callosobruchus maculatus (F.) (Coleoptera: Chrysomelidae) in storage’ was undertaken to understand the feasibility of utilizing few biologically based grain protectants in post harvest storage of cowpea by investigating their biological efficacy and persistent/ residual toxicity. The bioinsecticides under study were two entomopathogenic fungi Beauveria bassiana and Metarhizium anisopliae; spinosad, an actinomycete based broad spectrum insecticide with low mammalian toxicity and lemongrass oil- an essential oil from the aromatic plant, Cymbopogon flexuosus. Laboratory bioassays were carried out to investigate the dosage-mortality response of the bioinsecticides against C. maculatus. Toxicity of entomopathogens was studied by two bioassay techniques-direct dipping and residue film. B. bassiana and M. anisopliae were tested at five different concentrations 1 x 104, 1 x 105, 1 x 106, 1 x 107 and 1 x 108 spores/ml. Observations on mortality were taken at 24 hours interval upto five days. Results on the mortality of C. maculatus indicated an increase in mortality with increase in dosage and period of exposure. Cumulative mortality data of C. maculatus by B. bassiana and M. anisopliae at five days after treatment with five concentrations revealed no significant difference in mortality between the two entomopathogens and the two bioassay methods. Probit analysis of dosage-mortality response of B. bassiana and M. anisopliae indicated lower LC50 value for M. anisopliae than B. bassiana (5.12 x 106 and 6.7 x 106 spores/ml) than B. bassiana (5.38 x 106 and 7.49 x 106 spores/ml). However the difference was not remarkable. Time-mortality effect of B. bassiana and M. anisopliae indicated an increase in LT50 values as the spore concentration decreased. Toxicity of spinosad to C. maculatus was also investigated by direct dipping and residue film bioassay methods. LC50 of spinosad was 4.02 ppm by direct dipping where as a higher LC50 value (36.39 ppm) was observed by residue film bioassay. Spinosad brought about 50 per cent mortality in 20.51 to 33.09 hours and 90 per cent mortality in 2.6 to 3.3 days. Lemongrass oil, at eight concentrations (1 to 8 μl/l of air), was tested to study the fumigant toxicity action against C. maculatus and the mortality ranged from 16.67 to 96.67 per cent. Lemongrass oil caused 50 per cent mortality at 3.93 ppm in one day and 90 per cent mortality at 7.51 ppm in 2.6 days. Bio-efficacy of the four bioinsecticides along with coconut oil as a recommended check was assessed for a period of 30 days in the storage by studying their effects on adult mortality, fecundity, egg hatchability, progeny emergence, developmental period, extent of infestation, grain weight loss and seed viability. Regarding adult toxicity, lemongrass oil caused highest adult mortality (87.1 to 100%) followed by spinosad (75.87 to 100%) at three days after treatment. Spinosad was most effective as an inhibitor of oviposition and egg hatchability. On comparing the progeny emergence in different treatments, no progenies were produced in the cowpea grains treated with coconut oil. Spinosad and lemongrass oil also showed higher inhibition of progeny emergence. Data on the effect of bioagents on the extent of infestation by C. maculatus revealed that coconut oil was the most effective treatment as it caused zero infestation. Spinosad and lemongrass oil were the next effective ones as they resulted in 49 and 52 per cent reduction of seed damage. Entomopathogens were found to be ineffective in reducing bruchus damage to seeds. Effects on weight loss also recorded the same trend. Results on the impact of bioagents on seed viability indicated that spinosad treated grains showed the highest germination followed by lemongrass oil and coconut oil. Results of the persistent toxicity action of the tested bioinsecticides revealed that spinosad had highest persistence with a PT value of 5699.7. All other bioagents showed less persistence. Lemongrass oil showed the least persistent toxicity against in storage. It can be concluded from the present investigation that among the four bioagents, spinosad is the most effective one in terms of bioefficacy as well as persistent action in cowpea seeds. It can be recommended as an alternative option for bruchid management in storage. The existing recommendation of coconut oil is also proved to be effective against C. maculatus in storage of cowpea seeds. Lemongrass oil is also a very effective bioagent as a fumigant for protecting cowpea grains from C. maculatus with a limitation of short persistence that warrants frequent applications in storage. B. bassiana and M. anisopliae are not effective against C. maculatus in cowpea storage.ThesisItem Open Access Biological control of root-knot nematode, Meloidogyne incognita (Kofoid and White, 1919) in banana Musa (AAA) var. Robusta(Department of Agricultural Entomology, College of Horticulture, Vellanikkara, 2011) Lini, G; KAU; Susannamma KurienA study entitled ‘Biological control of root-knot nematode, Meloidogyne incognita (Kofoid and White, 1919) in banana, Musa (AAA) var. Robusta’ was carried out in the Department of Agricultural Entomology, College of Horticulture, Vellanikkara and Banana Research Station, Kannara during April 2010 to June 2011. The objective of the study was to identify an effective biocontrol agent for the management of root-knot nematode in banana. The species of root-knot nematode was identified and confirmed as M. incognita by the perineal pattern of the white females collected from the infested roots of banana plants from BRS, Kannara. Pot culture experiments were conducted to study the effect of different biocontrol agents viz., Arbuscular Mycorrhizal Fungi (AMF), Pseudomonas fluorescens, Paecilomyces lilacinus, Bacillus subtilis and Heterorhabditis indica (EPN) alone and in different combinations in comparison with the commonly used chemical nematicide, carbofuran on the management of root-knot nematode in banana. The effect of the treatments on the biometric characters of banana viz., height of the plant, girth of pseudostem and number of leaves were observed at monthly intervals. When the plants were about to form bunches (seven months after planting) these plants were uprooted and the effects of different treatments on various parameters viz., fresh weight of the whole plant, corm, roots, gall formation on roots and the nematode population in soil and roots were recorded. Among the various treatments tried, the combined application of P. fluorescens and P. lilacinus was found to be very effective in enhancing the biometric characters of banana which was on par with that of carbofuran, followed by P. lilacinus and AMF when treated alone, whereas EPN was found to be the least effective one With regard to nematode population in soil and roots, though carbofuran was found to be the best treatment, this was closely followed by P. fluorescens and P. lilacinus treatment. Same trend was noticed in the case of root knot index, gall formation, fresh weight of whole plant, corm and roots. Application of AMF and EPN were observed as the least effective treatments and recorded maximum nematode population both in soil and roots. . Considering the above results, the present study indicated that the combined application of P. fluorescens and P. lilacinus was found to be the most effective substitute for the chemical nematicide carbofuran for the management of root-knot nematode in banana.ThesisItem Open Access Infestation of the pumpkin caterpillar, diaphania indica saunders in cucurbits and its management(Department of Agricultural Entomology, College of Agriculture, Vellayani, 2011) Neena, Lenin; KAU; Hebsy, BaiSurvey conducted in the Kalliyoor panchayath of Thiruvananthapuram district during 2009-2010 revealed the incidence of the pumpkin caterpillar, Diaphania indica Saunders in bitter gourd, snake gourd, cucumber and coccinia. The extent of infestation was high in bitter gourd, snake gourd and cucumber and low in coccinia. The infestation was significantly higher during the fruiting followed by the flowering and vegetative stages. Leaves and fruits of bitter gourd, snake gourd and coccinia were damaged by the pest. Only the leaves of cucumber were damaged. No significant differences were noted in the extent of infestation when more organic manures or more fertilizers were applied by the farmers. Similarly, the high and low doses of fertilizers applied also did not influence the extent of damage. The plant protection measures adopted by the farmers too had no significant effect on the extent of damage. The red amaranth (Amaranthus tricolor Linn.) and green amaranth (Amaranthus dubius L.) and the weed plants, the slender amaranthus (Amaranthus viridis L.) and bristly starbur (Acanthospermum hispidum DC.) were recorded as host plants of D. indica. The parasitoid Apanteles sp. was the only natural enemy recorded during the survey. Among the botanicals screened, annona seed extract 5%, neem oil garlic emulsion 2%, neem seed kernel extract 5%, Anosom 2ml l-1, Derisom 2ml l-1 and NeemAzal T/S 2ml l-1 resulted in high mortality of the caterpillars upto three days after treatment both when applied topically and released on treated leaves. The efficacy of Anosom 2ml l-1 extended to the seventh day when released on treated leaves. Topical application of spinosad 0.015%, flubendiamide 0.004%, profenophos 0.05%, diafenthiuron 0.02%, triazophos 0.05% and chlorpyriphos 50%+ cypermethrin 5% 0.05% resulted in 100 per cent mortality of the caterpillars one day after treatment. When released on treated leaves, flubendiamide 0.004% and spinosad 0.015% proved to be the better treatments, registering mortality of the pest upto 15 days after treatment. 80 Field evaluation with annona seed extract 5%, Anosom 2ml l-1, B. bassiana 2g l-1, B. thuringiensis 2g l-1, flubendiamide 0.004% spinosad 0.015% and carbaryl 0.15% indicated that flubendiamide 0.004% was the most effective, the reduction in the pest population being 60 per cent. Spinosad 0.015% and Anosom 2ml l-1 also resulted in significant reduction in the pest population, the extent of reduction being 46 and 43 per cent, respectively. Annona seed extract 5% too was equally effective as Anosom 2ml l-1 in its efficacy, the population of the pest being reduced by 40 per cent. The extent of reduction in the pest population in carbaryl 0.15%, B. bassiana 2g l-1 and B. thuringiensis 2g l-1 treatments was 35, 35 and 33 per cent, respectively. More than 50 per cent reduction in the number of fruits damaged was recorded B. bassiana 2g l-1, flubendiamide 0.004%, B. thuringiensis 2g l-1 and spinosad 0.015% treatments. Anosom 2ml l-1 and annona seed extract 5% resulted in more than 40 per cent reduction in the fruit damage. Carbaryl 0.15% registered 39 per cent reduction in the fruit damage. All the treatments increased the yield of the crop significantly, the extent of yield increase ranging from 36 to 44 per cent in the insecticide, 39 to 41 per cent in the botanical and 26 to 39 per cent in the microbial treatments. Based on the results of the study, destruction of the weed and other volunteer host plants and early detection of the pest and its management with either the botanicals or microbials would be a viable option for controlling the pest. The safer insecticides flubendiamide 0.004% or spinosad 0.015% could be used when there is a substantial increase in the pest population.ThesisItem Open Access Characterization of bud necrosis virus infecting tomato(College of Agriculture, Vellayani, 2011) Simi, S; KAU; Umamaheswaran, KStudies were conducted to characterize the tospovirus causing the bud necrosis disease of tomato in Kerala. The characteristic symptoms observed were, necrotic ring spots on leaves and severe necrosis, death of the emerging buds, stem necrosis and concentric yellow colored rings on fruits. Host range studies were conducted and the virus was found to infect members of family Chenopodiaceae, Solanaceae, Fabaceae, and Cucurbitaceae. The virus was efficiently transmitted by mechanical means using 0.01 M phosphate buffer (pH 7.2) containing 0.1 per cent 2-mercaptoethanol. No seed transmission was recorded. However successful graft transmission was observed. The virus recorded a DEP in the range of 10-3 to 10- 4 , TIP of 50 oC to 55 oC, and LIV of 8 h at room temperature (28±2oC) and 24 h at 80C. The carbohydrate levels in inoculated plants were lower compared to the uninoculated tomato plants. Similarly the content of chlorophyll a, b and total chlorophyll were also lower in inoculated tomato plants. The phenol content was found to be more in inoculated plants. There was an increase in protein content in inoculated plants compared to the healthy plants. In case of inoculated plants the activity of the defense related enzymes were higher than the control plants. Protein profile of tospovirus infected tomato plants using SDS - PAGE showed three extra novel proteins with molecular weights of 28, 15 and 12 kDa respectively. Isozyme analysis of PPO produced three isoforms in both healthy and inoculated plants with relative mobility (Rm) values of 0.60 and 0.77. The activity of the two isoforms were more in the inoculated plants. The virus causing bud necrosis disease in tomato was confirmed as tospo virus by serological analysis such as ELISA and DIBA. The virus isolate showed close relationship with WSMV. The virus was also detected using PCR and an amplicon of size 800 bp was obtained using primer specific to tospovirus. The meristem from the infected tomato plants were regenerated into plantlets and were tested for the presence of the virus by subjecting it to DAC- ELISA. The absorbance of the plantlet regenerated from healthy and infected meristem were found to be 0.13 and 0.12 respectively which was on par with the healthy field sample but much lower than that of the infected field sample which was used as the positive control which recorded an absorbance of 0.81.ThesisItem Open Access Bioefficacy and safety evaluation of biorational insecticides for the management of sucking pest complex of chilli (capsicum annuum L. )(Department of Agricultural Entomology, College of Agriculture, Vellayani, 2011) Thania Sara Varghese; KAU; Thomas Biju Mathew