1. KAUTIR (Kerala Agricultural University Theses Information and Retrieval)
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Item Pests of medicinal plants in Kerala(Department of Agricultural Entomology, College of Agriculture , Vellanikkara, 2026) Hisana Jabeen, Vdicinal plants are known to Indian traditional healers since time immemorial. Kerala is known for its rich biodiversity of medicinal plants that support both traditional and modern healthcare practices. When cultivated in large areas, medicinal plants are much more prone to pest attacks, which cause considerable damage. Since limited information was available on pests of medicinal plants, the present study entitled "Pests of medicinal plants in Kerala" was conducted to document the pests associated with medicinal plants in the region, to generate DNA barcodes of cryptic species collected and to study the biology and population dynamics of indigo psyllid, Euphaleropsis isitis, an important pest of Indigofera tinctoria. Purposive sampling surveys were carried out in 32 locations across 10 districts of Kerala, covering 15 agroecological units distributed among five agroecological zones. The study documented 55 pest species associated with 10 selected medicinal plants viz., I. tinctoria, Ocimum spp., Coleus aromaticus, Plectranthus vettiveroides, Withania somnifera, Plumbago spp., Piper longum, Kaempferia galanga, Pseudarthria viscida and Desmodium gangeticum. Additionally, 17 species were recorded from 13 medicinal plants viz., Pogostemon cablin, Aristolochia indica, Tylophora indica, Asparagus racemosus, Thespesia populnea, Strobilanthes cusia, Saraca asoca, Tephrosia purpurea, Ruta graveolens, Aegle marmelos, Calotropis gigantea, Hibiscus sp. and Helicteres isora. Of the total pests collected, 31 were under the order Hemiptera, 24 Lepidoptera, 10 Coleoptera, two Orthoptera, one mite species and snail. This study revealed 40 new host associations and a new distributional record for Sphenoptera konbirensis (Coleoptera: Buprestidae). Barcoding of seven insect pests viz., Orphanostigma abruptalis, Bemisia tabaci, Aleurothrixus trachoides, Lygaeus sp., Cochlochila bullita, Icerya aegyptiaca and Plumbago leaf miner was done. For this, genomic DNA was isolated, mitochondrial cytochrome oxidase I (mtCO1) was amplified and sequenced. The in-silico analysis revealed that O. abruptalis, Lygaeus sp., B. tabaci, and A. trachoides showed more than 98 per cent similarity, whereas C. bullita, I. aegyptiaca and Plumbago leaf miner showed less than 93 per cent similarity with the available sequences in the NCBI database. The sequences were submitted to NCBI to obtain accession numbers and to BOLD for generating species specific barcodes. The indigo psyllid, E. isitis is a major pest infesting I. tinctoria. There were no comprehensive studies on the biology and factors affecting the population build-up of E. isitis on indigo plant. This study represented the first detailed investigation on the biology and population dynamics of the indigo psyllid. The biology was studied in the laboratory at ambient conditions to document its morphology and developmental duration. Eggs were elongate oval, pale yellow and later turned black, with an incubation period of 6 ± 0.77 days. The dorsoventrally flattened nymphs passed through five instars, completing development in 15.5 ± 1.75 days. The total life cycle lasted for approximately 21.5 days. Adults were small, with slender antennae, forewings marked with black spots and variable abdominal colouration. Females (2.62 ± 0.127 mm long, 0.92 ± 0.050 mm wide) were larger than males (2.24 ± 0.077 mm long, 0.88 ± 0.062 mm wide). Mean longevity was 17.4 ± 3.55 days in females and 16.4 ± 3.83 days in males. Females laid an average of 209.9 ± 61.83 eggs over a period of 13.1 ± 3.20 days with a brief pre-oviposition period of 2.2 ± 0.4 days. The population of different life stages of E. isitis, viz., egg, nymph and adult of psyllid, were recorded from September 2024 to August 2025 and correlated with the weekly average of one-week prior weather data. The population was comparatively higher during July-August. The abundant population of nymphs and adults during the rainy season could be attributed to the lush growth of the plant stimulated by rainfall. Egg did not show correlation with any weather factors. Nymph had positive significant correlation with rainfall. The adult exhibited a significant negative correlation with maximum temperature and bright sunshine hours. A significant positive correlation was observed between evening humidity and adult population, while rainfall displayed a highly significant positive correlation. A further study extending over 2-3 years is required to assess population dynamics and their correlation with weather factors.Item Variability studies in Bhringaraj(Eclipta prostrata L.)(Department of Plantation ,Spices, Medicinal And Aromatic Crops, College of Agriculture, Vellanikkara, 2024-12-23) Anite Titus.; Sangeetha, K SEclipta prostrata L. (Bhringaraj), a member of the Asteraceae family, stands out as a well-known medicinal plant, popularly surged due to its historical therapeutic use in Ayurveda, Unani and Siddha formulations and acknowledged pharmacological properties. Bhringaraj is popularly known as the king of hairs due to its immense potential to promote hair growth. Furthermore, it is renowned for its hepatoprotective, antioxidant, anti-inflammatory, anti-microbial, immunostimulant, antitumor, memory- enhancing, and anti-diabetic properties. Eclipta prostrata L. (vernacular names: false daisy, Bhringaraj, Keshraj, Karisalankanni, Kayyonni) is a herbaceous plant with diminutive branches and clusters of white axillary or terminal inflorescences, flourishes as an annual plant in moist habitats, where the whole plant holds substantial economic value. Despite its classification as Least Concern by the IUCN in 2016, there is a pressing necessity for the exploration and conservation of E. prostrata germplasm due to heightened demand for natural products leading to unsustainable harvesting practices. Scientific investigation is essential to elucidate the morphological characteristics, agronomic properties, and sustainable harvesting practices necessary for the conservation of its ecosystems, mainly focusing on the variability of genotypes suitable for commercial cultivation in India, especially in Kerala, where wild habitats are a primary source for medicinal plants. In this framework, the present investigation entitled “Variability studies in Bhringaraj (Eclipta prostrata L.)” was taken up with the objective of assessing the variability in morphological, yield, and quality parameters of Bhringaraj genotypes. The study was conducted at the experimental farm of the Department of Plantation, Spices, Medicinal, and Aromatic Crops, College of Agriculture, Vellanikkara, from 2023 to 2024. The study encompassed a total of twenty-five genotypes, which comprised collections from the ICAR-NBPGR Regional Station, Thrissur, as well as local collections sourced from various districts within Kerala, including Kottayam, Thrissur, Malappuram, Idukki, Trivandrum, Kasaragod, and Kollam. Significant variations in morphological, yield, and quality characters were identified through the examination of both qualitative and quantitative attributes. Qualitative traits, encompassing growth patterns, stem morphology, leaf and inflorescence characters, and seed attributes, weresystematically recorded, with the leaf attachment, leaf margin, inflorescence shape, and seed colour exhibiting no variability. Furthermore, considerable variations were noted in the quantitative characters pertaining to plant, leaf, inflorescence, and yield parameters. The biochemical metrics, encompassing total alkaloid, phenol, and saponin concentrations, exhibited a range of 0.60 to 6.20 per cent, 41.35 to 180.29 milligrams per gram, and 1.20 to 3.25 per cent, respectively, demonstrating notable variations. The comparative study of different solvents, comprising aqueous, ethanol, and methanol, in the preliminary phytochemical screening of E. prostrata demonstrated that ethanol was the most efficacious solvent for phytochemical extraction, followed by methanol for optimal yield. The evaluation of genotypic and phenotypic variance coefficients (GCV and PCV), alongside heritability and genetic advancement in E. prostrata accessions, indicated significant genetic diversity, as reflected by elevated GCV and PCV values across various traits such as plant height, number of primary and secondary branches per plant, number of nodes per plant, internodal length, leaf dimensions, days to first and 50 per cent flowering, and yield metrics. Thus, it suggested a broad genetic base with notable heritability and genetic gain, underscoring the significance of additive gene effects. Correlation analyses utilizing Pearson’s correlation coefficient indicated a noteworthy positive association between fresh whole plant yield per plant and various morphological traits, including plant height, internodal length, leaf length, leaf width, leaf area, and inflorescence diameter. Additionally, the total alkaloid content showed a substantial positive correlation with plant height, internodal length, leaf length, leaf width, leaf area, days to first flowering, and days to 50 per cent flowering. In contrast, a negative correlation was observed with the number of primary branches per plant. The evaluation and ranking of 25 E. prostrata genotypes based on yield-correlated traits led to the recognition of nine elite genotypes: EP 24, EP 7, EP 4, EP 11, EP 12, EP 16, EP 17, EP 20, and EP 15. Chemo profiling of methanolic extracts from selected nine superior genotypes and prostrate type, EP 23, through GC-MS analysis demonstrated a diverse range of phytochemicals, with n-hexadecanoic acid predominating in seven out of 10 genotypesWhile EP 15, EP 24, and EP 11 were characterized by major compounds including 6- [[5-(Hydroxymethyl)-2,5,8a-trimethyl-1,4,4a,6,7,8-hexahydronaphthalen-1-yl]methyl] -3-methylidene-7-oxabicyclo[4.1.0]heptane-2, 2-Hydroxy-3,5,6-trimethyl-benzo-1,4- quinone, and Quinic acid, respectively. Principal Component Analysis (PCA) of quantitative traits identified 19 principal components, where the leading five components collectively explained 78.39 per cent of the variance with eigenvalues greater than one, alongside with significant clustering in the second and third quadrants and a scattered distribution of accessions across all quadrants. Further, the K prototype cluster analysis utilising the Gower distance and Ward D2 clustering methods grouped the genotypes into five clusters based on 16 qualitative and 19 quantitative traits. The majority of accessions were classified within Cluster II (12), with lesser representation in Cluster III (6) and Cluster V (4). Conversely, Cluster I (1) and Cluster IV (2) exhibited the lowest number of accessions. The current study revealed substantial diversity in 41 traits, comprising 12 qualitative, 22 quantitative, and three biochemical, associated with morphological, yield, and quality characteristics among 25 genotypes of E. prostrata. Ethanol is the most efficient solvent for phytochemical extraction, with methanol being the second most effective. The nine superior genotypes were identified as superior with a noteworthy positive correlation between fresh whole plant yield and yield-associated morphological traits, combined with distinct phytochemical profile variations among accessions identified through GC-MS analysis. These genotypes could be pivotal in advancing crop enhancement and breeding high-yielding varieties through selective breeding, thus facilitating the commercial cultivation of the crop. Further evaluation may be done on the vegetative propagation of E. prostrata for quick enhancement of elite types. Comprehensive chemo profiling and molecular characterization of genotypes, alongside the assessment of their pharmacological properties and potential clinical trials involving animal experimentation, as well as screening for downy mildewresistance, may be conducted.Item Medicinal plants as intercrops in cassava (Manihot esculenta Crantz)(Department of Agronomy, College of Agriculture, Vellanikkara, 2021) Dayana Samson; Sindhu, P VKerala is considered a treasure house of medicinal and aromatic plants, however, due to indiscriminate harvesting; the existence of most of these plants is under threat. Cultivation is the only option to ensure the continual supply of high quality raw materials without diminishing natural resources. Due to small holding size and a greater focus on cash crops, the scope for commercial production of medicinal plants as a pure crop in Kerala is restricted. So, the practical alternative is to bring them under intercropping with priority crops such as food and commercial crops. Cassava (Manihot esculenta Crantz) is the most important starchy root crop grown in the tropics. The wide spacing, together with slow initial growth and development, makes cassava compatible to intercropping with short duration annual crops. The present study entitled “Medicinal plants as intercrops in cassava (Manihot esculenta Crantz)” was carried out at the Agronomy farm, Department of Agronomy, College of Agriculture, Vellanikara from September 2020 to April 2021 to assess the feasibility of intercropping cassava with the medicinal plants Indigofera tinctoria, Plectranthus vettiveroides and Sida alnifolia. The experiment was laid out in Randomized Block Design (RBD) with 10 treatments replicated thrice. The treatments included sole crops of cassava and medicinal plants, cassava + single row of medicinal plants, and cassava + double rows of medicinal plants. The observations on growth, yield and yield attributes of main and intercrops, and quality parameters of medicinal plants were recorded. Competitive indices and economics of cultivation were also computed. Intercropping significantly influenced the growth and yield attributes of both main and intercrops. With respect to plant height of cassava, significant variation was observed only at later stages of crop growth. Shorter cassava plants were observed when intercropped with Sida alnifolia (162.84 cm). In general, medicinal plants grown under intercropping system recorded taller plants, except for Indigofera, where sole cropping resulted in taller plants.The sole crop of cassava produced higher per plant tuber yield of 3.24 kg (32417 kg/ha) and was at par with cassava with single row of Plectranthus (3.12 kg/plant). The lowest tuber yield was recorded when cassava was intercropped with double row of Sida (1.77 kg/plant). Similar trend was observed in itop yield and dry matter production per plant. The yield of medicinal plants was the highest in sole crops, followed by single row intercropping and double row intercropping. Same trend was observed for quality parameters of medicinal plants. The quality of Indigofera tinctoria, expressed by indican content, was higher in sole crop (1.40 per cent) and was on par with single row inter crop (1.39 per cent). Sole crop of Plectranthus vettiveroides registered the highest essential oil content of 0.60 per cent, followed by cassava + single row of Plectranthus (0.40 per cent). Sole crop of Sida alnifolia produced highest total alkaloid (3.07 per cent) and was at par with single row intercrop (2.94 per cent). Cassavas intercropped with double rows of medicinal plants were more efficient in controlling weeds than sole crop of cassava or cassava + single row of medicinal plants. Sole crop of cassava recorded the highest total weed density and dry matter production at 30 DAP, 60 DAP and 90 DAP. Sida alnifolia controlled the weeds more effectively than other medicinal plants, both as sole crop or as intercrop with cassava. Competition indices like land equivalent ratio (LER), relative crowding coefficient (K or RCC), competitive ratio (CR), cassava equivalent yield (CEY) and aggressivity were assessed for evaluating intercropping efficiency. All intercropping systems recorded LER of values greater than one, indicating the yield advantage over sole cropping. The highest LER (1.41) was recorded when cassava was intercropped with double row double row of Plectranthus vettiveroides and LER was lower when Sida alnifolia was intercropped either as single row or as double rows (1.01 and 1.05 respectively). Higher RCC and CR values and positive aggressivity values for cassava indicated dominance of cassava over medicinal plants. K (RCC) of all treatments was greater than one, indicating yield advantage of the system. The highest CEY was recorded for cassava + Indigofera as double row, with cassava equivalent yield of 43895 kg/ha, and the lowest CEY was for sole crop of Sida alnifolia (3000 kg/ha). Among the medicinal plants evaluated, Indigofera tinctoria, either as double row or as single row, could be recommended as the best medicinal intercrop for cassava. Intercropping cassava with single row Plectranthus vettiveroides was the next best alternative.