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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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20211
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Subject: Plant Physiology × Author: Garggi, C × Author: KAU × Type: Thesis × Thesis Type: Ph.D ×
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    ThesisItemOpen Access
    Physiological and molecular studies on genera of loranthaceae and their management
    (Department of Plant Physiology, College of Agriculture, Vellanikkara, 2021) Garggi, C; KAU; Girija, T
    Hemiparasitic plants belonging to the family Loranthaceae are major tree parasites. Dendrophthoe falcata, Helicanthus elastica, Macrosolen capitellatus are major hemiparasites infecting perennial crops of the tropics. Helixanthera wallichiana and Taxillus tomentosus are two important hemiparasites infecting the fruit and timber trees of the high ranges. Apart from being a troublesome parasite they also serve as a linchpin reservoir supporting an extensive ecosystem. The prevailing investigation namely “Physiological and molecular studies on genera of Loranthaceae and their management” was carried out at Department of Plant Physiology, College of Agriculture, Vellanikkara, Thrissur, during the period from 2015 to 2020. Morphological characters of representative species viz., Dendrophthoe falcata, Helicanthus elastica, Macrosolen capitellatus, Helixanthera wallichiana and Taxillus tomentosus from five selected. Samples of these were collected from various locations from the plains and highranges of Thrissur. In all the selected species, leaves were oppositely arranged, D. falcata and H. elastica had oblong shaped leaves, leaves of M. capitellatus was lanceolate in shape, and H. wallichiana and T. tomentosus had narrow ovate shaped leaves. Fruit was berry in all the genera. Hemiparasites possess a physiological structure called haustoria through which they abstract water and minerals from the host. Haustorial branching pattern in all the genera was found to be basal epicortical root (ber). Haustorial portions of the collected samples were treated and prepared to permanent slides. Anatomical sections of the haustoria of the five selected genera of Loranthaceae revealed that there exists a transition zone between the host- parasite interphase region. This was observed as undifferentiated parenchymatous cells which aid in translocation of molecules. Presence of xylem elements were observed at the haustorial region. Haustorial anatomy of M. capitellatus was unique as there was complete merging of cells of host and parasite at the interphase region. The lineage of five selected genera belonging to Loranthaceae family were studied by molecular assay. The results from the ISSR assay revealed that, T. tomentosus and M. capitellatus had maximum similarity compared to all the other genera, since it formed a separate cluster. Morphological characterization indicated similarity between the two genera in the haustorial attachment pattern. Both the species have a single point of attachment to the host. H. wallichiana was observed to be more similar to the first cluster. D. falcata formed another branch close to H. wallichiana, where all these four genera formed the main group. H. elastica formed a separate lone group, which indicated genetical variance from other genera studied. Morphological observations supporting such a uniqueness in this parasite was noted in haustorial branching type, where basal epicortical root with lateral tendril like structures from nodes and internodes were observed. The parasite also showed other phylogenetically advanced characters according to Angiosperm Phylogeny Group (APG system) of classification like fused corolla and calyx. To study the host parasite interaction, root feeding studies with labelled 32P were undertaken. Cocoa plants infected with both parasites D. falcata and H. elastica was selected for the study. 32P in carrier solution of 1000ppm orthophosphoric acid @ 2 mCi per plant was fed to the surface running roots of cocoa. Leaf samples of the host and parasite were collected at 7 and 14 days after treatment and assayed for radio activity. To understand the translocation from parasite to host, leaves of the parasitic species both D. falcate and H. elastica were also smeared with labelled 32P and leaf samples were analysed from different parts of both the host and the parasite. These experiments were done on different trees. Leaf samples of the host and parasite were collected at 2, 7 and 14 DAT and assayed for radio activity. Results from the radio assay indicated that there is bidirectional movement of nutrients from host to parasite and parasite to host. There exists a prioritized partitioning pattern for nutrient transport (phosphorous) based on demand by the sink, regardless of the parent plant. The host and parasite were found to act as a single system indicating their coexistence. Physiological parameters of the host and parasites were also observed using InfraRed Gas Analyser (IRGA) for a period of six months. It was observed that stomatal conductivity of D. falcata and H. elastica was significantly higher than the host cocoa. Even though there was no much variation in the photosynthetically active radiation (PAR) received by the host and parasite during the period of observation, D. falcata and H. elastica had significantly higher rate of photosynthesis than cocoa. Transpiration rate of both parasites were significantly higher than their host. Carboxylation efficiency and light use efficiency of H. elastica were observed to be significantly higher than the host, cocoa. Field experiment was conducted to improve the management strategy and control the spread of the parasite. Use of surfactant was found to improve the efficacy of ethephon in controlling the regrowth of parasite on host plant. Non- ionic surfactants viz., Nonyl phenol ethoxylate (NPE) and Organosilicone (OS) were selected for the study. A combination of OS (0.5 ml/L) surfactant with ethephon (25ml/L) was successful in suppressing the regrowth of both D. falcata and H. elastica.