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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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20202
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Subject: Agricultural Entomology × Author: KAU × Author: Sachin G, Pai × Start date: 2020 × Type: Thesis ×
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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.
  • Thumbnail Image
    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.