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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 Population dynamics and management of erythrina gall wasp quardrastichus erythrinae kim.(Department of Agricultural Entomology, College of Agriculture, Vellayani, 2008) Beena, M P; KAU; Thomas Biju, Mathew. Studies were conducted to understand the population dynamics and management of Erythrina Gall Wasp (EGW)Quadrastichus erythrinae. An abstract of the work done and the results are given below. Population dynamics of Q.erythrinae was studied by observing weekly emergence of male and female insects from leaflets and petioles collected from field during the period from January 2006 to June 2007. The results showed that population was high in the months of July 2006, January 2007, April 2007 and June 2007.The present study indicated that the emergence od adult EGW was the highest from petioles. The increase in weight due to EGW infestation and gall production was the highest in the left lateral leaflets. Weekly mean population of EGW emerged during the period of study showed that the total number of male EGW (1096.36) was higher than the female insects emerged (763.13). Weekly mean population of the male and female emerged from the leaflets and petioles was correlated with weather parameters viz. maximum and minimum temperature. Maximum and minimum relative humidity and rainfall prevailed during the time of sampling, previous one week, previous 14 days,week 21 days before and week 28 days before. The results showed significant and positive correlation between population of male EGW and the minimum temperature, while no correlation existed between female population and other parameters studied. Comparison of biometric observation of uninfested and infested plant parts indicated that the weight of the leaflets and petioles increased significantly due to an increase in biomass. Due galling by EGW, the girth of the petioles was shortened to about one third of uninfested petioles. The emergence of EGW was maximum from petioled scored in the damage category ‘9’. Among the four groups of Erythrina stricta Roxb..stricta trees studied, based on the height of the trees, no group turned out to withstand the damage by EGW. Thiomethoxam, imidacloprid, carbaryl and acephate proved superior among the chemical tested insecticides tried against female and male EGW in the laboratory . Neem oil 2 per cent and neem oil-garlic 2 per cent proved superior among the botanical insecticides tried for protecting the newly formed side shoots. Among the systemic /translaminar insecticides applied on the galled plant parts, triazophos 0.05 per cent and imidacloprid .002 per cent were significantly superior in controlling the EGW emergence. In the field experiment conducted to evaluate insecticide-fungicide combination for EGW infestation and protection of the new side shoots, carbaryl 0.1 per cent and combination of imidacloprid 0.002 per cent and carbendazim 0.2 per cent effectively protected the side shoots up to 8 weeks after spraying. Residue analysis of dry pepper berries collected from pepper vines trailed, on the insecticide sprayed crythrina standards showed that residues at the time of harvest from trees sprayed with acephate 0.05 per cent dimethoate 0.05 per cent were below detectable limit. Where as the residues in pepper collected from lamda cyhalothrin 0.05 per cent and triazophos 0.05 percent treated trees was 1.38 ppm and 1.16ppm respectively. An overall analysis and interpretation of the data on population in relation to phenology to E.stricta foliar growth showed that there existed a six monthly cycle of damage by gall wasp resulting in complete defoliation of the trees by about six month followed by the next cycle of regrowth and re infestation .ThesisItem Open Access Bio-efficacy and molecular characterization of the native isolates of Bacillus thuringiensis Berliner(Department of Agricultural Entomology , College of Horticulture, Vellanikkara, 2008) Jyothi Sara, Jacob; KAU; Maicykutty, P MathewBacillus thuringiensis Berliner shortly known as B.t., is a gram-positive, spore forming bacterium that produces proteinaceous crystal containing insecticidal toxins. The host range of B.t. has expanded considerably due to extensive screening programmes. By virtue of its lack of toxicity towards other species of animals and human beings, B.t. has emerged as a safe candidate in the IPM programmes of various agroecosystems. Frequent exposure to one type of B. thuringiensis toxins can develop resistance in insects. Isolation of novel strains is important to overcome the onset of insect resistance. The present study on “Bio-efficacy and molecular characterization of native isolates of Bacillus thuringiensis Berliner” was conducted at the Department of Agricultural Entomology and CPBMB, College of Horticulture, Vellanikkara during the period from 2006 to 2008 with an objective to study the pathogenicity of 20 B. thuringiensis isolates collected from the Western Ghats of Kerala, one of the well known hot spots of biodiversity. The tobacco caterpillar, Spodoptera litura Fb. which was used as the test insect was reared in semi-synthetic diet (Ballal, 2004) and also in natural diet on castor leaves. The preliminary screening was performed for lepidopteran specificity with the ideal dose of 1 x 109 spores per ml showed that three isolates were toxic to S. litura. The per cent mortality caused by the lepidopteran effective isolates, namely, KAU-11, KAU-51, KAU-166 and the reference strain, HD-1 were 76.7 per cent, 80.0 per cent, 86.7 percent, 96.7 per cent respectively. A standardized bioassay was carried out with five different concentrations of all the selected isolates namely, KAU-11, collected from Thusharagiri (Calicut Dt.), KAU-51 from Kolahalamedu (Idukki Dt.), KAU-166 from Nelliyampathi(Palakkad Dt.) and the reference standard HD-1 (B. thuringiensis subsp. kurstaki). The mortality ranged from 63.3 to 100.0 per cent in various isolates and there was no significant difference between isolates. This indicated the equal effectiveness of the native isolates with the standard strain, HD-1. The LC5o value for the isolates was calculated by Finney’s Method of Probit Analysis. The lowest LC50 was obtained in KAU-51, with 6.3095 x 104 spores per ml and highest in KAU-11, with 1.2589 x 106 spores per ml. The lethal time to cause 50 per cent mortality (LT50) ranged from 44.4 h. to 96.0 h. in different isolates. The lowest LT50 was recorded in HD-1, which shows the ability of the standard to cause mortality slightly earlier compared to other isolates. The molecular characterization of the selected isolates was performed with RAPD-PCR technique. RAPD-PCR is a simple and rapid method for determining genetic diversity in various organisms and is a means of creating a biochemical finger print of an organism. Out of the 20 primers screened, 10 primers which produced more than five bands were selected for RAPD analysis. The RAPD data was used to generate a similarity matrix using the NTSyS programme. Clustering was done and dendrogram was drawn using Unweighted Pair Group Method of Arithematic Averages (UPGMA). The results showed that high variability exists between the selected isolates. Further studies are required to identify the subspecies of the efficient B.t. isolates to evaluate the field effectiveness against S. litura and other major lepidopteran pests for its utilization in pest management programmes. More primers need to be screened to study the genetic diversity of the isolates.ThesisItem Open Access Insect fauna on coconut (cocos nucifera L. ) spadix and effect of pesticides on major pollinators(Department of Agricultural Entomology, College of Agriculture, Vellayani, 2006) Shaiju, Simon; KAU; Devanesan, SAn investigation was carried out to document the different insect species visiting the coconut inflorescence, to find out the variations in the foraging activity of different insect species and to assess the relative safety/toxicity of some commonly used pesticides to honeybees. The study revealed that the coconut inflorescence attracted thirty different species of insects towards it. These insect species visited the inflorescence to feed on either pollen or nectar or both. Bees viz., Apis dorsata, A. mellifera, A. cerana indica, Trigona iridipennis, Braunsapis sp and Eupetersia sp were found to collect both pollen and nectar of which A. mellifera and A. cerana indica dominated. Bees were found to forage on the inflorescence throughout the day and exhibit a peak period of activity during 0900 h in case of A. mellifera and A. cerana indica and during 1200 h in case of T. iridipennis. All these species of bees exhibited two distinct peaks during the day of which the second peak was during 1500 h. They mainly collected pollen from half opened male flowers. Ant species that foraged on the coconut inflorescence in large numbers were Solenopsis geminata, Myrmicaria brunnea, Dolichoderus sp, Camponotus sericeus. They visited the inflorescence for feeding pollen and nectar. The population of ants remained more or less same throughout the day, they visited in higher numbers during 0900 h. They were present on the inflorescence throughout the day and maximum during 0900 h. Other insect species that visited the palm inflorescence were flies (Bactrocera cucurbitae, B. dorsalis, Musca domestica, Hemipyrellia sp., Graptomyza brevirostris and Sarcophaga sp.), wasps (Polistes hebraeus, Chalybion bengalense, Ropalidia variegata, Vespa cincta and Vespa sp.), beetles (Oxycetonia versicolor and Oxycetonia sp.) and moths (Euchromia polymena and Melanitis leda ismene). The maximum population of insects was observed on the 13th day of the male phase and in the female phase it was on the second day. The population fluctuations recorded over a period of one year showed that the occurrence of bees were the highest followed by the population of ants. Bees exhibited a significant positive correlation with maximum temperature and negative correlation with relative humidity and rainfall. The results on the evaluation of pesticides for their safety/toxicity to different species of honeybees indicated that all the chemical pesticides were toxic to honeybees. Carbaryl 0.1 per cent was the most toxic while endosulfan 0.05 per cent was the least toxic chemical. However, both azadirachtin 0.004 per cent and neem oil garlic emulsion 2.0 per cent were the safest treatments to honeybees under laboratory conditions.ThesisItem Open Access Pests of tropical mushroom and their management(Department of Agricultural Entomology, College of Agriculture, Vellayani, 2008) Princy, John J; KAU; Naseema, Beevi SThe occurrence of mushroom pests and their extent of damage in five different locations in Thiruvananthapuram district were studied in a survey conducted at monthly intervals for a period of one year from April 2006 to March 2007. An experiment was conducted to evaluate the efficacy of various botanicals and synthetic insecticides for the management of major pests of mushroom in the Mushroom house, Instructional Farm, College of Agriculture, Vellayani. The study revealed that the common pests of mushroom were springtails Seira sp., phorid flies Megaselia sp., sciarid flies, cucujoid beetle Cyllodes sp., staphylinid beetles viz., Staphylinus sp. and Scaphisoma nigrofasciatum Champ, noctuid moth, parasitic mite Poecilochirus necrophori Vitzthum, slugs and snails. Of these, the occurrence of Cyllodes sp., P. necrophori, noctuid moth, slugs and snails in oyster mushroom were reported for the fist time from Kerala. The common pests of mushroom namely Seira sp., Megaselia sp., S. nigrofasciatum, Cyllodes sp. were observed throughout the year in all the five locations. Staphylinus sp. was observed in three locations for a period of one year. P. necrophori and slug population were recorded only in one location from September 2006 to March 2007. Correlation studies between the population and extent of damage with weather parameters revealed that Seira sp., P. necrophori and slugs had positive correlation with relative humidity and rainfall, while it showed negative correlation with maximum temperature. Population of Megaselia sp., S. nigrofasciatum, Cyllodes sp., Staphylinus sp. were positively correlated with maximum temperature and negatively correlated with relative humidity and rainfall Efficacy of various botanicals and synthetic insecticides applied at different intervals after bed preparation on the incidence and extent of damage caused by mushroom pests in mushroom beds showed that lindane 0.05 per cent applied as floor treatment before bedding was the most effective. This was followed by dichlorvos 0.02 per cent and chlorpyriphos 0.02 percent applied at fifteenth day after bed preparation, which were at par. Among the various treatments adapted for the control of pests in mushroom, floor treatment with lindane before bedding has been found superior compared to other treatments. Considering a better control of pests and absence of residues, the floor treatment with lindane can be suggested for getting an effective control of pest, which presumed to result in a consequent higher yield.ThesisItem Open Access Insect community analysis in cucurbitaceous vegetables and impact of insecticides on insect pollinators(Department of Agricultural Entomology, College of Agriculture, Vellayani, 2007) Jangaiah, V; KAU; Devanesan, SA study was undertaken to document the various insects associated with cucurbitaceous vegetables in ten locations of Kalliyoor panchayat of Thiruvananthapuram district from March 2006 to February 2007. A field trial was also carried out to assess the impact of insecticides on the insect pollinators, natural enemies and pests. The total number of different species of insects recorded on the cucurbitaceous vegetables was found to be 47. Of these, the important groups of insects observed were Hymenoptera (28 per cent), Coleoptera (21 per cent), Lepidoptera (19 per cent), Hemiptera (17 per cent), Diptera (11 per cent) followed by Orthoptera and Thysanoptera (2 per cent each). Besides the insects, two species of spiders (Araneae) and one species of mite (Acariformes) were observed in three cucurbits. Bees were the predominant insect pollinators identified. Among the four species recorded, Apis cerana indica Fab. was the most abundant in oriental pickling melon and snake gourd. Trigona sp. was abundant in bitter gourd. Apis mellifera L. least visited the cucurbit flowers. Among the three cucurbitaceous vegetables, the highest insect pollinators activity was recorded in oriental pickling melon followed by bitter gourd and snake gourd. The peak period of activity of the pollinators was noted to be during 1000 hr to 1100 hr and 1500 hr to 1600 hr. Maximum foraging activity of different insect pollinators was recorded during the seventh week after sowing in bitter gourd and snake gourd and sixth week after sowing in oriental pickling melon. The population of insect pollinators was more in summer than rainy season. The higher activity of insect pollinators was observed under pesticide free condition in the Instructional farm when compared to farmer’s field where insecticides were frequently applied. The dominant insect pests recorded were Bactrocera cucurbitae Coq. and Aulacophora spp. followed by Aphis spp., Henosepilachna sp., Liriomyza trifoli Burgess, Diaphania indica Saunders, Anadevidia peponis Fb. and thirteen other pests. The highest fruit fly infestation was observed in bitter gourd (38.66 per cent) followed by snake gourd and oriental pickling melon. Pumpkin beetles caused up to 28.99 per cent damage in oriental pickling melon and 22.44 per cent in snake gourd. No infestation was observed in bittergourd. Two species of spiders(Oxyopes javanus Thorell and Lycosa pseudoannulata Boes et st.), three coccinellid beetles (Menochilus sexmaculatus Fab., Synharmonia octomaculata Fab. and Micraspis crocea Mulsant) and two parasitoids (Apanteles sp. and Chrysocharis johnsonii Walker) were the major natural enemies recorded. Foliar application of neem oil 2.0 per cent, imidacloprid 0.002 per cent and malathion 0.2 per cent proved to be safer to pollinators than other chemical insecticides. Imidacloprid 0.002 per cent and malathion 0.2 per cent significantly reduced pest infestation. Neem oil 2.0 per cent and imidacloprid 0.002 per cent were also safer to the natural enemies. The highest yield was recorded in imidacloprid 0.002 per cent treatment followed by malathion 0.2 per cent and carbaryl 0.1 per cent treated plot. Evidently, selective use of insecticides like imidacloprid 0.002 per cent and malathion 0.2 per cent could effectively check pest infestation without harming the pollinators and natural enemies in cucurbitaceous vegetable ecosystem.ThesisItem Open Access Potential of entomopathogenic nematodes for the management of weevil pests of banana (musa SP)(Department of Agricultural Entomology, College of Agriculture, Vellayani, 2007) Remya, K R; KAU; Sheela, M SA study was taken up, to isolate native entomopathogenic nematodes from banana rhizosphere, to standardize artificial media for the wax moth Galleria mellonella L., the trap insect of EPN, to identify cheap medium for the mass production of native EPN, to establish the potential of native isolates of EPN in comparison with the standard cultures by screening and to assess the potential of native isolates for the management of two major weevil pests of banana viz. , pseudostem weevil Odoiporus longicollis Oliv. and rhizome weevil Cosmopolites sordidus Ger. in the laboratory of Department of Agricultural Entomology, College of Agriculture, Vellayani during 2005-06. Native isolates of EPN were collected from banana rhizosphere in six blocks of the Instructional Farm, Vellayani covering an area of 75 ha. Out of the hundred samples processed, ten native isolates were obtained. Based on the mortality of grubs of pseudostem weevil in the laboratory, the native isolates N1 and N2 were selected for further studies. The G. mellonella larvae were fed with standard medium along with cheap media viz., M1, M2, M3 and M4. The result revealed that among the cheap media, maximum survival of larvae was recorded in M1 medium. The cost of preparation of standard medium used for the rearing was high as compared to other three media. The percentage reduction of cost of ingredients of M1, M2 and M3 media from the standard medium was 21.29, 34.87 and 21.67 respectively. Among the three media, minimum reduction in cost of ingredient was computed for M2 medium. But considering the number of larvae survived and mass multiplication rate M1 medium was promising. For mass multiplication of native EPN, the rate of multiplication of infective juveniles was assessed in G. mellonella reared in different cheap media along with standard medium. The result showed that all the EPN (H. indica, S. glaseri, N1 and N2) reared in standard medium recorded maximum emergence of infective juveniles. The studies on the rate of multiplication of native isolates along with standards revealed that initial inoculum of 10 infective juveniles per G. mellonella larva recorded maximum emergence of infective juveniles of all EPN except N2. But the native isolate N2 required an initial inoculum level of 25 IJ per G. mellonella larva for maximum emergence of infective juveniles of EPN. The results of the study revealed that maximum emergence of EPN including native isolates were recorded at 20 days after inoculation rather than 15, 10 and 7 DAI. In order to establish the potential of native isolates on the mortality of grubs and adults of pseudostem and rhizome weevil, trials were conducted in vitro condition and using infested pseudostem and banana rhizome in the laboratory condition. Maximum mortality of grubs and adults of the pseudostem and rhizome weevils were recorded at 72 hrs after treatment. Under in vitro conditions the inoculum required for getting maximum mortality of grubs of pseudostem weevil was 100 IJ per grub, while it was 200 IJ per grub in rhizome weevil. In the case of adult weevils, the inoculum level required to get maximum mortality was 200 IJ per adult in both the cases. But inside the pseudostem and banana rhizome both the grubs of pseudostem and rhizome weevils recorded maximum mortality with 100 IJ per grub. From this investigation it was evident that native EPN strains are available in different agro ecosystems and are more virulent than the standard ones. The rearing media for trap insect, G. mellonella was modified with cheap ingredients and there by reducing the cost of production to 21.29 per cent with out affecting the nutritional status and survival of different instars. Comparative efficacy of native isolates (N1 and N2) and standards were worked out for the management of grubs and adults of weevil pests of banana. An inoculum level of 100 IJ per insect recorded a mortality of above 80 per cent in vitro condition in rhizome and pseudostem weevils but it was reduced to 52 to 56 per cent inside the rhizome and pseudostem. Thus from these studies, mortality of grubs and adults of the weevils inside the banana pseudostem and rhizome required a minimum inoculum level of 200 IJ per insect.ThesisItem Open Access Pests of coccinia (cocinia grandis (L) voigt) and their management(Department of Agricultural Entomology, College of Agriculture, Vellayani, 2006) Vijayasree, V; KAU; Nalinakumari, TThe occurrence, distribution and magnitude of pests of coccinia in ten locations of Kalliyoor Panchayath in Thiruvananthapuram district were studied in a survey conducted at monthly intervals for one year. A field trial was carried out to evaluate the efficacy of various botanicals and chemical insecticides in managing the pests of the crop in the Instructional Farm, College of Agriculture, Vellayani. The results of the survey revealed that the dominant pests in coccinia were scale insect Saissetia hemispherica (Targ.), aphid Aphis spiraecola Patch, fruit fly Bactrocera cucurbitae Coq. and gall fly Lasioptera cephalandrae Mani. The minor pests recorded were leaf footed bug Leptoglossus australis F., pentatomid bug Aspongopus obscurus F., epilachna beetle Henosepilachna vigintioctopunctata F., pumpkin beetles viz., Aulacophora foveicolllis (Lucas), Aulacophora impressa Fabricius, Aulacophora bicolor Weber, vine borer Apomecyna saltator Fabricius leaf folder Diaphania indica Saunders and red spider mite Tetranychus sp. Very low infestation of green stink bug Nezara viridula Linn., mealy bug Ferrisia virgata (Ckll.) and woolly bear Pericallia ricini Fb. The infestation of coccinia by A. spiraecola, L. australis, N. viridula, H. vigintioctopunctata, A. bicolor, A. impressa and Tetranychus sp. was reported for the first time. Location wise variations in the incidence and distribution of the pest were noticed. All the major and minor pests except A. dispersus and Tetranychus sp. were observed through out the year. These pests were found only in summer season. Seasonal occurrence of the pests showed higher population and more damage in summer than rainy season. Five fold increase in the damage was caused by L. cephalandrae in summer. Among the various natural enemies observed, only the spiders were seen in all the locations and throughout the year. Correlation studies revealed strong positive correlation between maximum temperature and population of the pests and extent of damage. Rainfall had significant negative relationship with both population and extent of damage. An important finding of the present investigation was that the galls of L. cephalandrae served as the site for multiplication of B. cucurbitae. Eighty per cent of the fruits and thirty per cent of the galls showed infestation by B. cucurbitae. The number of fruit flies emerged from fruit and gall did not show any variation. Evaluation of botanicals and chemical insecticides against pests and spiders revealed that botanicals were effective in controlling all the pests except S. hemispherica and L. cephalandrae and the chemical insecticides were comparatively more effective in the management of the pests other than L. cephalandrae. Imidacloprid offered long lasting protection of the crop from S. hemispherica and A. spiraecola. All the treatments tried were safe to spiders. The findings of the study clearly indicated that coccinia is severely infested with two hemipteran and two dipteran pests resulting in heavy yield loss. Imidacloprid which was found to be the best treatment could be recommended for the management of the pests especially the hemipteran pests. The treatments failed to manage L. cephalandrae.ThesisItem Open Access Enhancing the performance of the egg parasitoid, Trichogramma.chilonis Ishii (Trichogrammatidae : Hymenoptera)(Department of Agricultural Entomology, College of Horticulture, Vellanikkara, 2006) Shajna, P K; KAU; Ranjith, A MA study entitled ‘Enhancing the effectiveness of the egg parasitoid Trichogrmma chilonis Ishii (Trichogrammatidae: Hymenoptera)’ was carried out at the College of Horticulture, Vellanikkara with the objectives of increasing the effectiveness of T. chilonis and to standardize the optimum storage period of the trichocards. A prototype of an olfactometer suitable to monitor the movements of T. chilonis was at first made using polyester film for standardizing the design. The prototype was validated by keeping the kairomones in each of the four arms. As this was found to be a success, it was further fabricated in transparent acrylic sheet incorporating slight modifications. Various error factors were identified during the continued studies and they were eliminated and an improved design was standardized as uniform air inflow olfactometer. The responses of T. chilonis to different semiochemicals were studied in the uniform air inflow olfactometer. A higher response of adult parasitoids was noticed towards moth extracts of C. medinalis and Corcyra cephalonica and also moth scale extract of C. cephalonica in hexane solvent. This may be because hexane could extract more concentration or wider range of the kairomones which attract the parasitoids. The results corresponding to the response to plant volatiles emanating from the weeds in the paddy ecosystem are a clear pointer to the ecological adaptation of T. chilonis for survival. The highest attraction was towards the leaf folder damaged leaves followed by plant parts of Oryza rufipogon. Among the different semiochemicals, significant attraction was towards 10 per cent honey solution. The results thus established that a band or grid application of honey solution will increase the longevity of adults as well as the per cent parasitism. The adult moth which is the primary producer of eggs is the most preferred from among the different life stages of C. medinalis tried. A wind tunnel set up was fabricated to evaluate the olfactory responses of T. chilonis to the best semiochemicals. The distance travelled by the parasitoids was observed for every 30 minutes, for a total duration of three hours. Maximum distance travelled by the adult parasitoids was towards honey solution. The results validate the findings observed using the four arm olfactometer (free choice test) with a single source wind tunnel (no choice test). The effect of refrigerated storage on the emergence and parasitization efficiency of T. chilonis was studied. More than 50 per cent emergence was noticed up to 36 days in four day old cards which is of interest to nucleus stock of Trichogramma being maintained at the laboratories. The results of the study have shown that the Trichogramma emergence can be delayed even up to 50 days under ordinary refrigerated storage. Such cards even with around 10 per cent efficiency would be more economical than continuous rearing of Corcyra culture and production of trichogrammatids. Even for farmer situations, it may be more advisable to manage initial leaf folder populations at its first level of emergence itself. At this time the population is very low and even a 10 per cent parasitoid emergence can easily take care of first generation of leaf folder.ThesisItem Open Access Biology and insecticide sensitivity of rice white backed planthopper, Sogatella furcifera (Horvath) (Hemiptera:Delphacidae) in Kerala(Department of Agricultural Entomology, College of Horticulture, Vellanikkara, 2006) Prathibha, P S; KAU; Mani ChellappanAmong planthoppers infesting rice, white backed planthopper (WBPH), Sogatella furcifera (Horvath) (Hemiptera: Delphacidae) has become a menace to rice growers recently. Biology of the S. furcifera studied during winter (December) and summer months (March) showed a shorter incubation period and nymphal duration in summer when compared to the winter. The developmental cycle was longer in December. The fecundity of S. furcifera was more during March. But the per cent hatchability was higher in December. However, there was no significant difference in the per cent survival of WBPH over two seasons. The sex ratio exhibited significant difference in two seasons with more number of males during March than that in December. Population build up studied under laboratory condition recorded a reduction in fecundity of WBPH in the second generation. Feeding study conducted by honeydew test revealed that adult females produced more feeding damage than the adult males and any other stages of WBPH. The insect excreted two amino acids (glutamic acid and aspartic acid) along with the honeydew. The important natural enemies recorded were spiders (Argeops sp., Lycosa pseudoannulaata, Oxyopus spp., Thomisus spp. and Salticus spp.) and mirid predator, Cyrtorhinus lividipennis (Reut.). Two entomopathogenic fungi isolated from WBPH were identified as Aspergillus flavus (Dirk.) and Penicillium oxalicum (Currie & Thomb). This is the first report of above mentioned entomopathogenic fungal infection on WBPH. Imidacloprid and lambda cyhalothrin were more toxic to WBPH nymphs and recorded lower LC50 values. Among the tested insecticides, higher relative toxicity (compared to imidacloprid) was exhibited by lambda cyhalothrin. Under laboratory condition, phosphamidon and monocrotophos were more persistent insecticides which persisted for seven days while the DDVP persisted only for three days. There was a slight reduction in total protein content in insecticide treated samples compared to the untreated ones.