Browsing by Author "Nagaraja, N.R."

Now showing 1 - 20 of 28
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    A new pod bioassay method to determine the toxicity of insecticides against Tea mosquito bug, Helopeltis theivora
    (2024) T. N. Madhu; Saneera, E.K; R. Thava Prakasha Pandian; Sujithra, M; Bhavishya; Nagaraja, N.R.; Elain Apshara, S.; Josephrajkumar, A.; Rajesh, M.K
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    Arecanut
    (2017) Nagaraja, N.R.; Ananda, K.S.; Rajesh, M.K
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    Arecanut dwarf hybrids
    (2021) Nagaraja, N.R.; Ananda, K.S.
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    Arecanut leaf sheath: An alternate cattle feed
    (2013-06) Jaganathan, D.; Nagaraja, N.R.; Purandhara, C.
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    Biology and cultivation of arecanut
    (2018) Nagaraja, N.R.; Ananda, K.S.; Rajesh, M.K.
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    BORDEAUX MIXTURE - A UNIVERSAL BLEND FOR Phytophthora MANAGEMENT IN ARECANUT
    (2020) Thava Prakasa Pandian, R.; Shivaji Hausrao Thube; Chaithra, M.; Nagaraja, N.R.; Bhavishya; Ganesh N. Khadke; Jose, C.T.
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    Development of rapid, efficient and cost effective screening technique for testing arecanut against Phytophthora meadii incitant of fruit rot disease
    (2024) Prathibha, P.S.; Nagaraja, N.R.; Rajesh, M.K.; Daliyamol; K. P. Thejasri; Rajkumar; Vinayaka Hegde; Uchoi Anok
    To accelerate identification of disease resistant arecanut germplasm or hybrids against Phytoph- thora , it is very much imperative to develop bioassays which could differentiate resistant and susceptible cultivars efficiently. Here, a cost effective and rapid technique, called the “Detached Leaf Assay ”, was developed to identify resistant germplasm at the seedling stage itself. Zoospore production in highly virulent Phytophthora meadii (P19) was standardized by incubating under a 12 hours light and dark regime. Zoospore suspension was adjusted to 105 spores ml-1 in Petri plates. Subsequently, surface sterilized arecanut leaves were floated in zoospore suspension and incubated at temperature of 24 ± 1 °C. Disease symptoms, including water-soaked lesions, were recorded three days after inoculation. Infection lesion increased from 1 to 7.3 cm2 . The pathogen was re-isolated and confirmed with the original culture. The assay was successfully validated to screen arecanut accessions, wild types and hybrids against P. meadii . This technique is the first to be developed, and it is simple, cost-effective, and faster. It also provides consistent infection and could be effectively utilized to screen arecanut germplasm or hybrids against P. meadii in the seedling stage itself.
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    Elemental Composition of Betel Leaves Using a Novel Optical Spectroscopic Technique
    (2023) Kripa Adlene Edith A; Ravikiran Ongole; Unnikrishnan V. K; Adarsh U. K; Nagaraja, N.R.
    Objective: Assess trace elements in betel leaves and slaked lime from different regions of Karnataka, India using Laser Induced Breakdown Spectroscopy (LIBS). Materials and Method: Betel leaves from six different regions of Karnataka were obtained and named (for the purpose of the study) BL1, BL2, BL3, BL4, BL5, and BL6 and they were sun-dried. A single tube of slaked lime was obtained from the local ‘paan’ shop. Each dried leaf and a single blob of slaked lime was subjected to elemental analysis using Laser-induced breakdown spectroscopy. Results: A ten-trial experiment was carried out in all six leaves and a blob of the slaked lime. The National Institute of Standards and Technology (NIST) database was used to assess the emission lines. The elements that were predominantly present in all six betel leaves from different regions of Karnataka are calcium, copper, and iron. Slaked lime showed only the presence of calcium. Conclusion: It is widely accepted that the consumption of betel quid causes various changes in the oral mucosa including oral potentially malignant disorders (OPMDs) and oral cancer. It is important to analyze each component of betel quid to understand the disease progression. Copper is found to be relatively higher in betel leaves, and it is known that copper-induced fibrogenesis via the lysyl oxidase pathway in oral submucous fibrosis.
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    AN EMERGING PEST IN ARECANUT : PENTATOMID BUG,Halyomorpha picus
    (2020) Shivaji Hausrao Thube; Saneera, E.K; Pandian, R.T.P.; M. Chaithra; Nagaraja, N.R.; Priya, U.K; Bhavishya
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    Evaluation of microsatellite markers for genetic diversity analysis among different accessions of arecanut (Areca catechu L.)
    (2012-11) Bharath, B.G.; Ananda, K.S.; Rajesh, M.K.; Nagaraja, N.R.; Rijith, J.
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    Farmers' Participatory Demonstration On Arecanut Based Cropping System -A Success Story
    (2017) Jaganathan, D.; Nagaraja, N.R.; Jose, C.T.; Rajkumar; Ananda, K.S.; Thamban, C.
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    Flow Cytometric Based Estimation of Genome Size in Arecanut (Areca catechu L.) Varieties
    (2023) Kavyashree; Sowmyashree Sharma; Nagaraja, N.R.; N. Ranjini; Niral, V.; Beeranthadka Rajesh
    The present work was undertaken with the objective to estimate the nuclear DNA content in arecanut varieties using flow cytometry. Released varieties of arecanut maintained in the field gene bank at ICAR-Central Plantation Crops Research Institute (ICAR-CPCRI), Regional Station, Vittal, Karnataka, were used for the estimation of DNA content by using BD AccuriC6 flow cytometer. Nuclei isolated from leaves of Pisum sativum cv. Citrad of known genome size was used as an external reference standard. Significant differences were observed between the arecanut varieties for 2C DNA content. Among the arecanut varieties, 2C DNA content (genome size) was found to be ranging from 6.025 (2.946 Gb/1C) to 6.710 pg (3.281 Gb/1C), with mean value of 6.472 pg (3.164 Gb/1C). The highest DNA content was recorded in the variety Swarnamangala (6.710 pg/2C or 3.281 Gb/1C), followed by Sumangala (6.695 pg/2C or 3.273 Gb/1C) and Shatamangala (6.623 pg/2C or 3.238 Gb/1C), while the lowest DNA content of 6.025 pg/2C or 2.946 Gb/1C was recorded in the variety Sreemangala. The results of this study indicate the potential of using flow cytometry for studying genome size diversity in arecanut.
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    Genetic Diversity Studies and Screening for Fusarium Wilt (Fusarium udum Butler) Resistance in Wild Pigeonpea Accessions, Cajanus scarabaeoides (L.) Thouars
    (2016) Nagaraja, N.R.; Arun Kumar, M.B.; Manjunath Prasad, C.T.; Rajkumar; Parimal Sinha; Jaagrati Jain
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    Genetics of resistance to stem rust against Indian races in wheat varieties, Kundan and UP 2338
    (2014-09) Nagaraja, N.R.; Anupam Singh; Pallavi, J.K.; Sharma, J.B.; Karnam Venkatesh; Singh, G.P.; Neelu Jain; Prabhu, K.V.
    The parents, F1 and F2 individuals of the crosses Kundan x Agra Local, UP 2338 x Agra Local and Kundan x UP 2338 were screened to study the genetics of resistance in the Ug99-resistant varieties of wheat, Kundan and UP 2338 against two Indian stem rust pathotypes 40A (62G29) and 122 (7G11). Against race 40A (62G29), the variety Kundan did not have any resistance alleles, whereas, UP 2338 exhibited the presence of dominant resistance gene. The 195 F2 individuals of the cross UP 2338 × Agra Local and Kundan × UP 2338 segregated at a ratio of 3(R):1(S). Against stem rust pathotype 122 (7G11), the variety Kundan displayed monogenic dominant resistance. The resistance x resistance cross Kundan x UP 2338 also displayed resistance reaction in the F2 generation with no segregation indicating the presence of common gene in both the parents (Kundan and UP 2338) conferring resistance against the pathotype 122.
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    Good Agricultural Practices in Arecanut Cultivation
    (2025-01-01) Bhavishya; Ravi Bhat; Sujatha, S.; Rajesh, M.K.; Nagaraja, N.R.; Thava Prakasa Pandian, R.; T. N. Madhu
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    In vitro assay for screening of Areca spp. for Phytophthora resistance
    (2018) Muralikrishna, K.S.; Sharadraj, K.M; Gangaraj, K.P.; Nagaraja, N.R.; Anitha Karun; Rajesh, M.K.; Chowdappa, P.
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    Inter-specific hybrids in Areca spp.: Verification using SCoT markers
    (2024) Rajesh, M.K.; Nagaraja, N.R.; Sabana, A.A.; Muralikrishna, K.S
    Disease resistance has been a major goal in crop improvement programmes in arecanut (Areca catechu L.), where the fruit rot disease or Mahali, caused by Phytophthora meadii, is a major production constraint in India. The wild Areca spp., such as A. triandra and A. concinna, have been reported to possess resistance to P. meadii. Developing inter-specific hybrids between A. catechu and A. triandra or A. concinna could be one of the strategies to introgress the disease-resistant trait from the wild Areca spp. into cultivated arecanut. In this study, we report the utilization of start codon targeted (SCoT) markers to differentiate A. catechu from A. triandra and A. concinna and the development of sequence-characterized amplified region (SCAR) markers to enable authentication of true inter-specific hybrids between them. The technique would effectively verify inter-specific hybrids at the seedling stage itself.
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    Major storage insect pests of Arecanut Areca catechu L.: A Survey
    (2017) Shivaji Hausrao Thube; RTP Pandian; Bhavishya; Saneera, E.K; Chandrika Mohan; Nagaraja, N.R.
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    MANAGEMENT OF ROOT GRUB IN ARECANUT WITH ENTOMOPATHOGENIC NEMATODES -A SUCCESS STORY
    (2018) Rajkumar; Jaganathan, D.; Shivaji Hausrao Thube; Nagaraja, N.R.; Vinayaka Hegde; Ravi Bhat