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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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Subject: Agricultural Entomology × Author: KAU × End date: 2020 × Type: Thesis × Thesis Type: M.Sc ×
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    ThesisItemOpen Access
    Diversity of root mealybugs of Kerala
    (Department of Agricultural Entomology, College of Horticulture, 2020) Sachin G, Pai; KAU; Deepthy, K B
    Mealybugs (Homoptera: Pseudococcidae) are oval, soft bodied insects causing severe damage to plants not only by sucking the sap but also as vectors of viral diseases of crop plants. The mealybugs infesting roots of crop plants are termed as subterranean mealybugs or root mealybugs. Honeydew excreted by mealybugs attracts ants, and in turn they provide protection to mealybugs from their natural enemies and also help in transportation to other fields. Recently, root mealybug infestation was reported from different localities of Kerala. However, studies on diversity of root mealybug - ant association and seasonal incidence were scanty. Hence the present study, ‘Diversity of root mealybugs of Kerala’ had been carried out to identify the root mealybugs and associated ant species and to study the seasonal incidence, host range and geographical distribution of major root mealybugs. Purposive sampling surveys were carried out at different districts of Kerala covering 30 locations and 11 host plants. The root mealybugs and associated ants were collected separately in vials with 90 per cent ethanol. The specimens were labeled with sample codes and preserved as per standard protocols. The study revealed the presence of eight species of root mealybugs belonging to five genera viz., Formicococcus Takahashi, Planococcus Ferris , Dysmicoccus Ferris, Antonina Signoret and Xenococcus Silvestri. Maximum diversity was found in the genus Formicococcus, representing three species viz., Formicococcus polysperes Williams, Formicococcus lingnani Ferris and Formicococcus mangiferacola Williams. The genus Planococcus was represented by Planococcus lilacinus and Planococcus sp. The genus Dysmicoccus, Antonina and Xenococcus were represented viz., Dysmicoccus brevipes Cockerell, Antonina graminis Maskell and Xenococcus annandalei Silvestri, respectively. Three species viz., F. lingnani, F.mangiferacola and A. graminis were recorded for the first time from Kerala. The root mealybug, F.polysperes was recorded to be having wider host range and was found infesting black pepper, banana, avocado and goat weed. Pineapple mealybug, D. brevipes was recorded on pineapple and nut grass, while Planococcus sp. was reported on durian and black pepper. Root mealybugs, F. lingnani, F. mangiferacola, A. graminis, P. lilacinus and X. annandalei were recorded from single host plant each viz., nut grass, mango, paragrass, coffee and cardamom respectively. The morphological identification of ants associated with root mealybugs revealed seven species of ants of which maximum number of ant species were associated with root mealybug, F. polysperes. The ants associated with F. polysperes were Nylandria indica Forel, Tapionoma indicum Forel, Myrmicaria brunnea Saunders, W.W. and Crematogaster rogenhoferi Mayr . The ant associated with F. lingnani was N. indica; while Carebara affinis Emery with D. brevipes and Paratrechina longicornis Latreille with Planococcus sp. on pepper. Ant seen in association with the subterranean mealybug, X. annandalei was Acropyga acutiventris Roger. Among the ant species, N. indica was found to be the major species associated with Formicococcus from Kasaragod, Kannur, and Wayanad districts. The major root mealybug species, F. polysperes was, noted from seven locations of three districts viz., Kasaragod, Kannur and Wayanad respectively. The root mealybugs, F. lingnani, F. mangiferacola, A. graminis, P. lilacinus and Planococcus sp were reported from Wayanad whereas D. brevipes was recorded from Wayanad and Thrissur districts. Molecular characterization of root mealybugs and ants was performed by isolation of genomic DNA and amplification of mitochondrial cytochrome oxidase one (mtCO1) locus using specific primers. The sequencing of polymerase chain reaction (PCR) product and in- silico analysis of eight species of mealybugs and one species of ant was carried out. The sequence data of the following four root mealybugs viz., F. mangiferacola, F. lingnani, A. graminis and X. annandalei were absent in the NCBI data base. The sequences of these mealybugs were deposited in the NCBI database for the first time. Remaining four species of mealybugs showed 91-100 per cent similarity and were in agreement with the morphological identification. The sequences were submitted to NCBIGenbank for future access and use. The sequences were also uploaded to Barcode of Life Data systems (BOLD) and generated barcodes for eight species of mealybugs and one species of ant. The study on seasonal incidence of root mealybug F. polysperes showed that the population of mealybugs increased during rainy season from June and reached its peak in the month of September when the rains subside. The population was least during the summer months. Correlation of mealybug population with weather parameters indicated a significant negative correlation with maximum soil temperature and significant positive correlation with relative humidity and number of rainy days.
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    ThesisItemOpen Access
    Taxonomy of the tribe epilachnini (Coleoptera: Coccinellidae) of Kerala
    (Department of Agricultural Entomology, College of Horticulture, Vellanikkara, 2020) Beegam Salma, M P; KAU; Vidya, C V
    Coccinellidae, the lady beetle, is the largest family under the superfamily Coccinelloidea and is rich with nearly 6000 described species worldwide. Coccinellids are ecologically and morphologically diverse and exhibit a wide range of food habits spanning kingdoms and trophic levels. Majority of them are predaceous, while some are phytophagous and some mycophagous. Strictly herbivorous coccinellids are recognized under the tribe Epilachnini.Both the grubs and adults of epilachna beetles scrape the soft tissue on the surface of leaves, masticate it and suck the juice. In spite of its economic importance, no comprehensive studies have been carried out so far to explore the diversity of Epilchnini of Kerala. The study entitled “Taxonomy of tribe Epilachnini (Coleoptera: Coccinellidae) of Kerala” was carried out inthe Department of Agricultural Entomology, College of Horticulture, Vellanikkaraduring 2018-2020 with the following objectives: (1) taxonomy of the tribe Epilachnini in different agricultural ecosystems of Kerala and (2) prepare an illustrated key for the identification of the species of Epilachnini Purposive surveys were conducted in different districts of Kerala covering 25 locations in different agricultural ecosystems.The adults were collected by hand picking and sweeping while the immature stages viz., eggs, grubs and pupae were collected along with the associated host plants and reared to adult stage. Adults were usually collected from the upper surface of leaves whereas the immature stages from the lower surface. Wet and dry preservations were followed for temporary and permanent storage, respectively. The specimens were mounted on triangular card points and labelled with details on locality, date of collection, collector’s name and host plant. The specimens were then dried in oven at 50-60ºC for 1-2 weeks and stored for further studies.Specimens available in the Department of Agricultural Entomology, College of Horticulture, Vellanikkara and College of Agriculture, Padannakkad were also used for the study. The beetles were first grouped based on their host plant and elytral pattern. The specimens were then dissected and taxonomic characters viz., antenna, mouth parts, tarsal claw, post coxal line, male and female genitalia were studied. Descriptions, illustrations and key to genera and species of Epilachnini of Kerala were prepared. The specimens were identified upto species levelbased on the available literature and taxonomic keys. Host range and distribution of species were studied and distribution map was prepared using Quantum GIS software. The study recognized seven species belonging to four genera viz., Afidenta Dieke, Affisa Dieke,Afidentula Kapur and Henosepilachna Li. Three species under Henosepilachna were identified upto species level viz., Henosepilachnadodecastigma Wiedemann, H. septima Dieke and H. vigintioctopunctata Fabricius The species identified under Afidenta and Afidentula included Afidenta misera Weise and Afidentula bisquadripunctata. Two species studied under Affisaare A. flavicollis (Thunberg) and A. nilgirica(Weise). Afissa nilgirica was earlier described under the genus Epilachna. As per the new generic classification of Epilachnini this species belongs to Afissa and hence transferred to Afissa and this is a new combination. Fourteen host plants were identified for Epilachnini in Kerala which included plants belonging to Fabaceae, Cucurbitaceae, Solanaceae, Poaceae and Urticaceae. Epilachna beetles exhibited oligophagy in their feeding habit, with each species showing preference to plants belonging to a particular family. Henosepilachnavigintioctopunctata always preferred solanaceous plants, whereas H. septima preferred cucurbitaceous plants. Similarly, Afidenta misera preferred plants belonging to Fabaceae and Affisanilgirica prefered members of family Urticaceae. Henosepilachnaseptima and H. vigintioctopunctatawere found to be the most widely distributed species in the study area. Apart from crop plants, some of the weeds were also reported as the host plants of epilachna beetles. This study documented the faunal composition of Epilachnini of Kerala, their host range, and geographical distribution. The information generated can be effectively utilized in planning management strategy against epilachna beetles on major crops.
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    ThesisItemOpen Access
    Morphological variations of root knot nematode in vegetables and banana
    (Department of Agricultural Entomology, College of Agriculture, Vellayani, 2017) Chinchu, P Babu; KAU; Narayana, R
    The study entitled “Morphological variations of root knot nematode in vegetables and banana” was conducted at College of Agriculture, Vellayani during 2015-17 with the objective to study the morphological and morphometric variations of root-knot nematode in brinjal, okra, tomato and banana in Kerala. Morphological and morphometrical studies of females, perineal pattern, second stage juveniles and males of root knot nematodes collected from Dhanuvachapuram, Kattakada and Vellayani of Thiruvananthapuram district; Balagram, Pampadumpara and Thovalappady of Idukki district; Chazhoor, Thalikulam and Thaniyam of Thrissur district infecting brinjal, okra, tomato and banana were done and the data was analysed to identify the species. M.incognita (Kofoid & White, 1919) Chitwood, 1949, M. javanica (Treub, 1885) Chitwood, 1949, M. arenaria (Neal, 1889) Chitwood, 1949 and M. chitwoodi Golden, O'Bannon, Santo & Finley 1980 were identified from brinjal, okra, tomato and banana in Thiruvananthapuram, Idukki and Thrissur districts of Kerala. The study indicated M. incognita as the major species of root knot nematode in Thiruvananthapuram district (91.66%) with highest percentage of occurrence in brinjal and tomato (27.77). In Idukki district, the major species of root knot nematode was M. javanica (66.66%) with highest percentage of occurrence from brinjal and banana (33.33). In Thrissur district, M. arenaria was found to be the major species (66.66%) with highest percentage of occurrence in okra (37.5). M. incognita was found to be the major species in brinjal (55.55%), okra (44.44%), tomato (55.55%) and banana (44.44%) in Thiruvananthapuram, Idukki and Thrissur districts. The extent of parthenogenesis of root knot nematode was found to be very high (97.22%) in these populations. Intraspecific morphological variations were observed within M. incognita, M. javanica and M. arenaria with respect to shape of females, length and position of neck, perineal pattern morphology, tail characters including rectum dilation. Interpopulation comparison of mature females, perineal pattern and second stage juveniles of M. incognita showed that the characters length, width, neck length, stylet length, LMB, WMB and ratio a of females, LVS, AVS, ATT and IPD of perineal pattern and body length, stylet length, H-MB, ABW, tail length, ratio c and c’ were recorded as stable characters. Interpopulation comparison of mature females, perineal pattern and second stage juveniles of M. javanica showed that all the characters of females, perineal pattern and second stage juveniles were stable characters and in M. arenaria, the characters like body length, width, neck length, stylet length, LMB and WMB of females, LVS, AVS, ATT and IPD of perineal pattern and length, stylet length, H-MB, ABW and tail length were recorded as stable characters and found useful in characterizing species. Intraspecific morphological and morphometric variations of M. incognita, M. javanica, M. arenaria were recorded from four host plants in three districts in Kerala. M. arenaria and M. javanica showed high variability between the populations compared to M. incognita in Kerala. The study indicated that M. incognita, M. javanica and M. arenaria were the major species infesting vegetables and banana in Kerala. Among the sampled populations, M. hapla was not identified which shows that M. hapla is not common in Kerala conditions. The study recorded the first report of species having morphological and morphometrical characters similar to M. chitwoodi from okra in Thiruvananthapuram which opens way to molecular studies in future.
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    ThesisItemOpen Access
    Diversity of root mealybugs of Kerala
    (Department of Agricultural Entomology, College of Horticulture, Vellanikkara, 2020) Sachin G, Pai; KAU; Deepthy, K B
    Mealybugs (Homoptera: Pseudococcidae) are oval, soft bodied insects causing severe damage to plants not only by sucking the sap but also as vectors of viral diseases of crop plants. The mealybugs infesting roots of crop plants are termed as subterranean mealybugs or root mealybugs. Honeydew excreted by mealybugs attracts ants, and in turn they provide protection to mealybugs from their natural enemies and also help in transportation to other fields. Recently, root mealybug infestation was reported from different localities of Kerala. However, studies on diversity of root mealybug - ant association and seasonal incidence were scanty. Hence the present study, ‘Diversity of root mealybugs of Kerala’ had been carried out to identify the root mealybugs and associated ant species and to study the seasonal incidence, host range and geographical distribution of major root mealybugs. Purposive sampling surveys were carried out at different districts of Kerala covering 30 locations and 11 host plants. The root mealybugs and associated ants were collected separately in vials with 90 per cent ethanol. The specimens were labeled with sample codes and preserved as per standard protocols. The study revealed the presence of eight species of root mealybugs belonging to five genera viz., Formicococcus Takahashi, Planococcus Ferris , Dysmicoccus Ferris, Antonina Signoret and Xenococcus Silvestri. Maximum diversity was found in the genus Formicococcus, representing three species viz., Formicococcus polysperes Williams, Formicococcus lingnani Ferris and Formicococcus mangiferacola Williams. The genus Planococcus was represented by Planococcus lilacinus and Planococcus sp. The genus Dysmicoccus, Antonina and Xenococcus were represented viz., Dysmicoccus brevipes Cockerell, Antonina graminis Maskell and Xenococcus annandalei Silvestri, respectively. Three species viz., F. lingnani, F.mangiferacola and A. graminis were recorded for the first time from Kerala. The root mealybug, F.polysperes was recorded to be having wider host range and was found infesting black pepper, banana, avocado and goat weed. Pineapple mealybug, D. brevipes was recorded on pineapple and nut grass, while Planococcus sp. was reported on durian and black pepper. Root mealybugs, F. lingnani, F. mangiferacola, A. graminis, P. lilacinus and X. annandalei were recorded from single host plant each viz., nut grass, mango, paragrass, coffee and cardamom respectively. The morphological identification of ants associated with root mealybugs revealed seven species of ants of which maximum number of ant species were associated with root mealybug, F. polysperes. The ants associated with F. polysperes were Nylandria indica Forel, Tapionoma indicum Forel, Myrmicaria brunnea Saunders, W.W. and Crematogaster rogenhoferi Mayr . The ant associated with F. lingnani was N. indica; while Carebara affinis Emery with D. brevipes and Paratrechina longicornis Latreille with Planococcus sp. on pepper. Ant seen in association with the subterranean mealybug, X. annandalei was Acropyga acutiventris Roger. Among the ant species, N. indica was found to be the major species associated with Formicococcus from Kasaragod, Kannur, and Wayanad districts. The major root mealybug species, F. polysperes was, noted from seven locations of three districts viz., Kasaragod, Kannur and Wayanad respectively. The root mealybugs, F. lingnani, F. mangiferacola, A. graminis, P. lilacinus and Planococcus sp were reported from Wayanad whereas D. brevipes was recorded from Wayanad and Thrissur districts. Molecular characterization of root mealybugs and ants was performed by isolation of genomic DNA and amplification of mitochondrial cytochrome oxidase one (mtCO1) locus using specific primers. The sequencing of polymerase chain reaction (PCR) product and in- silico analysis of eight species of mealybugs and one species of ant was carried out. The sequence data of the following four root mealybugs viz., F. mangiferacola, F. lingnani, A. graminis and X. annandalei were absent in the NCBI data base. The sequences of these mealybugs were deposited in the NCBI database for the first time. Remaining four species of mealybugs showed 91-100 per cent similarity and were in agreement with the morphological identification. The sequences were submitted to NCBIGenbank for future access and use. The sequences were also uploaded to Barcode of Life Data systems (BOLD) and generated barcodes for eight species of mealybugs and one species of ant. The study on seasonal incidence of root mealybug F. polysperes showed that the population of mealybugs increased during rainy season from June and reached its peak in the month of September when the rains subside. The population was least during the summer months. Correlation of mealybug population with weather parameters indicated a significant negative correlation with maximum soil temperature and significant positive correlation with relative humidity and number of rainy days.
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    ThesisItemOpen Access
    Taxonomy of the tribe epilachnini (Coleoptera: Coccinellidae) of Kerala
    (Department of Agricultural Entomolgy, College of Horticulture, Vellanikkara, 2020) Beegam Salma, M P; KAU; Vidya, C V
    Coccinellidae, the lady beetle, is the largest family under the superfamily Coccinelloidea and is rich with nearly 6000 described species worldwide. Coccinellids are ecologically and morphologically diverse and exhibit a wide range of food habits spanning kingdoms and trophic levels. Majority of them are predaceous, while some are phytophagous and some mycophagous. Strictly herbivorous coccinellids are recognized under the tribe Epilachnini.Both the grubs and adults of epilachna beetles scrape the soft tissue on the surface of leaves, masticate it and suck the juice. In spite of its economic importance, no comprehensive studies have been carried out so far to explore the diversity of Epilchnini of Kerala. The study entitled “Taxonomy of tribe Epilachnini (Coleoptera: Coccinellidae) of Kerala” was carried out inthe Department of Agricultural Entomology, College of Horticulture, Vellanikkaraduring 2018-2020 with the following objectives: (1) taxonomy of the tribe Epilachnini in different agricultural ecosystems of Kerala and (2) prepare an illustrated key for the identification of the species of Epilachnini Purposive surveys were conducted in different districts of Kerala covering 25 locations in different agricultural ecosystems.The adults were collected by hand picking and sweeping while the immature stages viz., eggs, grubs and pupae were collected along with the associated host plants and reared to adult stage. Adults were usually collected from the upper surface of leaves whereas the immature stages from the lower surface. Wet and dry preservations were followed for temporary and permanent storage, respectively. The specimens were mounted on triangular card points and labelled with details on locality, date of collection, collector’s name and host plant. The specimens were then dried in oven at 50-60ºC for 1-2 weeks and stored for further studies.Specimens available in the Department of Agricultural Entomology, College of Horticulture, Vellanikkara and College of Agriculture, Padannakkad were also used for the study. The beetles were first grouped based on their host plant and elytral pattern. The specimens were then dissected and taxonomic characters viz., antenna, mouth parts, tarsal claw, post coxal line, male and female genitalia were studied. Descriptions, illustrations and key to genera and species of Epilachnini of Kerala were prepared. The specimens were identified upto species levelbased on the available literature and taxonomic keys. Host range and distribution of species were studied and distribution map was prepared using Quantum GIS software. The study recognized seven species belonging to four genera viz., Afidenta Dieke, Affisa Dieke,Afidentula Kapur and Henosepilachna Li. Three species under Henosepilachna were identified upto species level viz., Henosepilachnadodecastigma Wiedemann, H. septima Dieke and H. vigintioctopunctata Fabricius The species identified under Afidenta and Afidentula included Afidenta misera Weise and Afidentula bisquadripunctata. Two species studied under Affisaare A. flavicollis (Thunberg) and A. nilgirica(Weise). Afissa nilgirica was earlier described under the genus Epilachna. As per the new generic classification of Epilachnini this species belongs to Afissa and hence transferred to Afissa and this is a new combination. Fourteen host plants were identified for Epilachnini in Kerala which included plants belonging to Fabaceae, Cucurbitaceae, Solanaceae, Poaceae and Urticaceae. Epilachna beetles exhibited oligophagy in their feeding habit, with each species showing preference to plants belonging to a particular family. Henosepilachnavigintioctopunctata always preferred solanaceous plants, whereas H. septima preferred cucurbitaceous plants. Similarly, Afidenta misera preferred plants belonging to Fabaceae and Affisanilgirica prefered members of family Urticaceae. Henosepilachnaseptima and H. vigintioctopunctatawere found to be the most widely distributed species in the study area. Apart from crop plants, some of the weeds were also reported as the host plants of epilachna beetles. This study documented the faunal composition of Epilachnini of Kerala, their host range, and geographical distribution. The information generated can be effectively utilized in planning management strategy against epilachna beetles on major crops.
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    ThesisItemOpen Access
    Pongamia oil soap for the management of major pests of chilli (Capsicum annum L.)
    (Department of Agricultural Entomology, College of Agriculture, Padannakkad, 2020) Veena Krishna, K V; KAU; Sreekumari, K M
    The efficacy of the pongamia oil soap was tested at different concentrations in controlling the major pests of chilli, viz., whitefly, aphid (Aphis gossypii Glover) and mite (Polyphagotarsonemus latus Banks) under the project entitled ‘Pongamia oil soap for the management of major pests of chilli (Capsicum annuum L.)’. Laboratory bioassay was conducted to evaluate the effective repellency and oviposition repellency of pongamia oil soap against the adults of solanum whitefly, Aleurothrixus trachoides Back. Net house study of whitefly was performed in the Department of Agricultural Entomology, College of Agriculture, Padannakkad. Treated and control plants were randomly placed in a net house and whiteflies were released on the next day morning. There were seven treatments (T1: Pongamia oil soap 3%; T2: Pongamia oil soap 2%; T3: Pongamia oil soap 1%; T4: Pongamia oil soap 0.6%; T5: Soap solution 0.5%; T6: Water spray; T7: Control) with three replications. Number of adult whiteflies settled and eggs laid on the leaves in the treated and control plants were counted on the 1st, 3rd, 5th and 7th day after release and the repellence was computed. Statistical design CRD was used for the assessment of data obtained. Effective repellence and oviposition repellence of pongamia oil soap against the whitefly were directly proportional to concentration and indirectly proportional to time. The plants treated with pongamia oil soap effectively repelled the whitefly from settling over the treated surface. The 3% pongamia oil soap was found superior with 86.10% repellence one day after the release of whiteflies and it was followed by the 2% pongamia oil soap. All the concentrations of pongamia oil soap showed 100% repellence on the first day after the release and prevented egg laying. Pongamia oil soap (3%) was highly effective with 72.24 % oviposition repellence even after 7 days of spray. Field study was carried out at Instructional farm II of College of Agriculture, Padnnakkad at Karuvacheri during November 2019 to May 2020. The variety used was Vellayani Athulya. The statistical design followed was RBD with eight treatments and 2 three replications. The following are the treatments applied - T1: Standard check – Spiromesifen 22.9 SC @ 96 g a. i. / ha; T2: Pongamia oil soap 3%; T3: Pongamia oil soap 2%; T4: Pongamia oil soap 1%; T5: Pongamia oil soap 0.6%; T6: Neem oil soap 0.6%; T7: Soap solution 0.5%; T8: Control. The treatments were applied three times in the field at 2, 3 and 5 months after transplanting. Major sucking pests (whitefly, aphid and mite) and the natural enemies (spiders, coccinellids and predatory mites) were counted in the field study. Observations were made one day prior and 1, 3, 5, 7 and 14 days after treatment for the pests and natural enemies. Damage symptoms like leaf curling and malformed fruits were counted 7 and 14 days after the treatments. Spiromesifen was found effective against the sucking pests of chilli and showed persistent action in the field, whereas pongamia oil soap reported an immediate control over the pests but its effectiveness declined with time and concentration. Among the botanicals, 3% pongamia oil soap was found effective against whitefly, aphid and mite and was followed by the 2% per cent pongamia oil soap. Pongamia oil soap proved its effectiveness against these pests up to seven days after the treatment and the effect declined by 14 days after the spray. The soap solution (0.5%) always reported high population of pests compared to other treatments indicating that soap has no role in the effect of pongamia oil soap. Pongamia oil soap was found safe to spiders and coccinellids. But it reduced the population of predatory mites in the field. Leaf curl index and per cent fruit malformation recorded the minimum value in standard check and pongamia oil soap (3%) sprayed plots. This shows that these treatments are the highly effective against mites. Thrips infestation was negligible in the field and thus it was not recorded. Maximum fruit length was recorded from the standard check followed by pongamia oil soap 3 per cent treated plot. Standard check and pongamia oil soap 3 per cent exhibited higher fruit yield and marketable yield. Standard check recorded the highest BC ratio among the treatments. Economics of pongamia oil soap (3%) in terms of BC ratio was also high as compared to other treatments and control. All the concentrations of pongamia oil soap showed slight phytotoxicity when it was applied during extreme summer months. The study shows that pongamia oil soap is effective in protecting chilli crop from sucking pests and can be a component in chilli IPM.
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    ThesisItemOpen Access
    Flight range colony characteristics and pollination efficacy of stingless bee Tetragonnula travancorica in chilli (Capsicum annuum L.)
    (Department of Agricultural Entomology, College of Agriculture, Vellayani, 2020) Bindu, G; KAU; Shanas, S
    The study entitled “Flight range, colony characteristics and pollination efficacy of stingless bee Tetragonula travancorica in chilli (Capsicum annuum L.).” was conducted at Department of Agricultural Entomology, College of Agriculture, Vellayani, during the year 2018- 2020 with an objective to study the flight range, colony characteristics and pollination efficacy of stingless bee Tetragonula travancorica in chilli. To determine the flight range of stingless bees, artificial food bait was standardized and the standardized food bait was used as attractant in order to calculate the foraging distance. Colony composition of ten well maintained stingless bee hives were determined by counting the population of queen and workers and also, the internal nest characteristics like brood area and storage pots were determined. The brood area temperature was recorded from four well maintained stingless bee colonies with the help of data loggers. Stingless bee hives made out of four different wood types were exposed to 40ºC inside hot air oven for 3hrs in order to evaluate their temperature variation. Pollination efficacy of stingless bees in chilli was determined by comparing yield from self- pollination, open pollination and stingless bee pollination respectively. The study on standardization of food bait for determining flight range revealed that, 35 % sugar concentration was the food bait preferred by stingless bees, which is on par with 35 % honey concentration. The maximum foraging distance of stingless bee was found to be 378m and an inverse relation between distance travelled by the bees and their numbers were observed. Observations on brood area inside the hive revealed that, length, breadth and height of brood area varied between 6cm to 16cm, 4cm to 12cm and 4cm to 12cm respectively. Brood volume varied from 96 cm3 to 1147.5 cm3. Volume of pollen pots varied from 21cm3 to 105 cm3. Volume of honey pots varied from 0.021L to 0.250L. The population of queen was similar in all 10 hives i.e. one in number and population of workers varied between seven hundred to three thousand two hundred and fifty-five numbers. The brood area temperature and RH of stingless bee hives varied between 22.9ºC to 33ºC and 71.7 % to 93.3 % respectively. The temperature and relative humidity inside empty hive varied between 24.1ºC to 33.4 ºC and 73.1 % to 98.1 % respectively. It was inferred that the stingless bees have the ability to control humidity and temperature inside the hive. Bridelia was the best wood type for making stingless bee hives, which control temperature control inside the hive effectively. Bridelia wood exhibited an average temperature control of 39.56ºC followed by Terminalia with 38.2ºC and the lowest temperature control was recorded in jack wood (31.86ºC). The time trend followed by the wood types to reach 40ºC was least in Bridalia followed by Terminalia, Teak and Jack. Pollination efficiency was maximum in stingless bee pollination followed by open and self-pollination with average fruit set percentage of 82.74%, 69.69% and 62.41% respectively. Number of fruits /plant, yield/ plant, weight of the fruit and percentage fruit set was highest in stingless bee pollination. The percentage increase in yield was 42% over control and percentage increase in fruit number and fruit weight was 18% over the control.
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    ThesisItemOpen Access
    Melissopalynological studies of stingless bee Tetragonnula travancorica (Apidae: Meliponini)
    (Department of Agricultural Entomolgy, College of Agriculture, Vellayani, 2020) Lincy, Abraham; KAU; Shanas, S
    The present investigation entitled “Melissopalynological studies on stingless bee Tetragonula travancorica (Apidae: Meliponini)” was conducted at the Department of Agricultural Entomology, College of Agriculture, Vellayani, during 2017-2020. The objective was to study the foraging activity of stingless bee T. travancorica Shanas and Faseeh and to identify its floral pollen resources occurring in Thiruvananthapuram district. Eighteen locations were selected across the district on the basis of land elevation and composite sampling of pollen and honey was done purposively from hive during the three seasons, viz. Northeast monsoon season (October- December), Dry season (January- May) and Southwest monsoon season (June- September). The collected samples were processed and analysed using standard acetolysis procedure recommended by the International Commission for Bee Botany (Louveaux et al., 1978). The pollen load in honey samples were determined and pot pollen collected during the period was subjected to metabarcoding. Foraging activity of stingless bees in the hive was studied and observations were recorded fortnightly from 0600 hrs to 1800 hrs during all the three seasons from November to August. In the study, out of 115 plant types recorded as foraging sources, 93 were identified. Sixty-seven plants were identified up to the species level, 16 to genus level and 10 up to family level. Important species identified were Cocos nucifera, Mimosa pudica, Mimosa diplotricha, Milletia pinnata, Macaranga peltata, Alternanthera sessilis, Areca sp., Peltophorum pterocarpum, Sweitenia mahagoni, Tridax procumbens, Mikania micrantha, Amaranthus spinosus, Amaranthus viridis, Borassus flabellifer, Ageratum conyzoides, Ceiba pentandra, Passiflora edulis, Caesalpinia echinata, Boerrhavia diffusa, Amaranthus hybridus, Delonix regia, Terminalia arjuna, Psidium guajava, Psidium araca, Momordica charantia, Eucalyptus sp., Glochidion sp. and Syzygium cumini. The most predominant were pollen of Cocos nucifera, Mimosa pudica and Milletia pinnata during all seasons. The secondary pollen types observed were Macaranga peltata, Tridax procumbens, Sweitenia mahagoni, Peltophorum pterocarpum, Amaranthus spinosus, Alternanthera sessilis and Areca sp. Most frequently observed pollen type in honey samples were C. nucifera and M. pinnata whereas C. nucifera and M. pudica were very frequent in pollen samples common to all seasons. The botanical family which had the highest recorded pollen type was Fabaceae (8) followed by Asteraceae (7) and Myrtaceae (7). Metabarcoding of pollen revealed that Amaranthus tuberculatus, A. spinosus, A. caudatus, A. hybridus, A. hypochondriacus, A. palmeri, Malvales sp., Benincasa hispida, Lagenaria siceraria and Muntingia calabura were the predictable candidates as observed by their bit scores and E-value. The total pollen count of honey samples ranged from 27,000 TNP/mL (Group II) to 2, 94,000 TNP/mL (Group III). A marked difference was observed between mid-land and upland and also among locations during both the seasons. The pollen count in midlands was lower during dry season whereas during northeast monsoon season the pollen count in uplands was radically lowered. Foraging activity of stingless bees revealed that the highest activity occurred during March and April (hotter months) while the lowest during December and January (colder months). The maximum number of outgoing and incoming foragers with pollen was recorded during April, March and February whereas, incoming foragers without pollen was highest during March, April and May. The highest average of outgoing foragers and incoming foragers with pollen load was observed during 0900 to 1200 hrs while, in incoming foragers without pollen load, it was from 1000 to 1300 hrs. The ratio of pollen foragers to total incoming foragers was highest during November followed by December and the least during May and June. Thus, melissopalynological studies revealed the presence of 115 foraging sources for T. travancorica in Thiruvananthapuram district while foraging studies revealed maximum foraging activity during hot dry season. The study highlights that the stingless bees exploit diverse floral resources available in their surroundings.
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    ThesisItemOpen Access
    Tortoise beetles (Coleoptera : Chrysomelidae: Cassinae) of Kerala
    (Department of Agricultural Entomology, College of Agriculture, Vellayani, 2020) Amritha Hari; KAU; Prathapan, K D
    Taxonomic studies on Tortoise beetles (Coleptera: Chrysomelidae: Cassidinae) of Kerala were made with the objectives of identification of tortoise beetles of Kerala, provide descriptions and diagnosis of tortoise beetle taxa of Kerala and to gather information on host plants and distribution. Three hundred and eleven specimens from 48 locations were studied. The study treated 33 species of cassidines belonging to 11 genera under four tribes. Ten species previously recorded from the state could not be collected or studied. Description and diagnosis of all the taxa studied are provided. Information on distribution and host plants are also given. The study recognizes 43 species of tortoise beetles, belonging to 11 genera classified under four tribes in Kerala. Of the 12 cassidine tribes, Aspidimorphini, Basiprionotini, Notosacanthini and Cassidini occur in Kerala. Cassidini is the largest tribe represented by 18 species in four genera (Cassida, Chridopsis, Oocassida and Silana), followed by Aspidimorphini with 10 species in 3 genera (Aspidimorpha, Laccoptera and Nilgiriaspis). Basiprionotini, which are large tortoise beetles, are represented by five species in three genera viz. Basiprionota, Craspedonta and Epistictina. Notosacanthini, with a single genus Notosacantha, includes 10 species in Kerala. One genus (Basiprionota) and eight species here recorded are new to Kerala. The species newly recorded for Kerala are Cassida nysea Spaeth, 1926, Craspedonta leayana Latreille, 1807, Nilgiraspis andrewesi Spaeth, 1932, Notosacantha bifenestrella (Boheman, 1862), Notosacantha maduraensis Swietojanska, 2006, Notosacantha shibathai Kimoto, 1981, Notosacantha vicaria Spaeth, 1913 and Oocassida cruenta (Fabricius, 1792), of which Notosacantha shibathai is new to India as well. Trophic selections of cassidines are skewed towards members of Covolvulaceae, followed by Asteraceae, Rhamnaceae, Amaranthaceae, Bignoniaceae, Euphorbiaceae, Rhizophoraceae, Rutaceae, Fabaceae and Verbenaceae. Seven cassidine species are reported as pests of sweet potato (Aspidimorpha furcata, A. fuscopunctata, A. miliaris, A. sanctaecruces, Laccoptera nepalensis, Cassida circumdata and Chiridopsis bipunctata). Craspedonta lealyana on Gmelina arborea, Silana farinosa on curry leaf, Murraya koenigii and Epistictina reicheana on Stereospermum colais are serious pests.