Browsing by Author "Daliyamol"

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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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    First report on the association of ‘Candidatus Phytoplasma asteris’ with lethal wilt disease of coconut (Cocos nucifera L.) in India
    (2020) Merin Babu; Thangeswari, S.; Joseph Rajkumar, A.; Krishnakumar, V.; Karthikeyan, A.; Selvamani, V.; Daliyamol; Vinayaka Hegde; Maheswarappa, H.P.; Anitha Karun
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    An Insight into the Regime of Soil Borne Plant Pathogens
    (2018) Daliyamol; Merin Babu; Rajeev, G.
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    An Insight into the Regime of Soil Borne Plant Pathogens
    (2018) Daliyamol; Merin Babu; Rajeev, G.
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    Intercropping of fruit crops in Coconut garden Vignettes from 'Chowtara thota' Meevapadavu
    (2021-01) Thamban, C.; Shameena Beegum; Prathibha, P.S.; Daliyamol
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    Interlinking Coconut with Microbes
    (2017-10) Indhuja, S.; Daliyamol; Merin Babu
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    Matrix Ranking- An important PRA tool to assess farmers preferences and priorities
    (2017) Mahesh, V.; Swathi Lekshmi, P.S.; Dilip Ananda Pawar; Daliyamol; Alok Kumar; Prakash, P.
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    Multi-gene phylogeny and phenotypic analyses revealed an association of different Colletotrichum species with inflorescence dieback and leaf spot of arecanut in India
    (2024) Prathibha, V.H.; Rajesh, M.K; Akshay Dinesh; Balanagouda Patil; Daliyamol; Nagaraja, N.R.; Rajkumar; Sabana, A.A.; K.P. Gangaraj; K.P. Thejasri; Sunil S. Gangurde; Vinayaka Hegde
    Arecanut is one of the economically important plantation crops. Among the various diseases, inflorescence dieback and leaf spot/blight diseases caused by Colletotrichum spp. have re-emerged as major factors impeding arecanut production in India in the last few years. To understand the Colletotrichum species complex in the arecanut system, we have characterized Colletotrichum spp. associated with inflorescence dieback and leaf spot/ blight of arecanut based on a combination of phenotypic, multi-locus (ITS, ACT, CHS-1, GAPDH, HIS3 and TUB2) phylogeny and pathogenicity studies. A total of 26 Colletotrichum isolates were obtained from arecanut inflorescence dieback (13 isolates) and leaf spot/blight (13 isolates) infected tissues collected from disease-endemic regions of Karnataka, Kerala and Tripura states of India. The combined multi-locus sequence analyses and a critical examination of phenotypic characters revealed the association of Colletotrichum aoteaora as a dominant species with arecanut inflorescence dieback disease. On the other hand, two Colletotrichum species, viz., C. siamense and C. fructicola, were distinctly associated with leaf spot/blight disease. All the Colletotrichum isolates studied were pathogenic to arecanut. Significant variations in lesion size were observed among the different species with cross-infection ability on inflorescence and leaves. This study represents the first comprehensive study of Colletotrichum spp. associated with arecanut inflorescence dieback and leaf spot/blight diseases. In addition, the study is the first record of C. aoteaora, C. siamense, and C. fructicola associated with the arecanut crop in this country. It provides valuable information for implementing effective IDM strategies against these diseases in India.
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    National Symposium Sustainable Plant Health Management Amidst Covid Pandemic: Challenges and Strategies 1- 3 December 2021
    (2021) Rajesh, M.K.; Joseph Rajkumar, A.; Prathibha, V.H.; Daliyamol; Jilu V. Sajan; Merin Babu; Thava Prakasa Pandian
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    Outbreak of new fungal disease in coconut gardens of Northern Kerala
    (2022-07) Daliyamol; Thamban, C.; Vinayaka Hegde
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    Perspectives on the cardioprotective, neuroprotective and anti-obesity functions of coconut (Cocos nucifera L.)
    (2024) Shameena Beegum; Ramesh, S.V.; Pandiselvam, R.; Neema, M.; Daliyamol; Manikantan, M.R.; Hebbar, K.B
    Widely acclaimed as the "tree of life," the coconut is intrinsically woven into human culture as a source of food, shelter, and medicine. Coconut oil and its derivatives have found diverse applications in both food and industry. Of late, the consumption of coconut in the form of oil and its derivatives has been proven to be beneficial. Taking into account the most recent clinical evidences, an attempt was made to present a concise review of the cardioprotective, neuroprotective, and anti-obesity effects of coconut and its derivatives. Our analysis reveals that research evidence supports the cardioprotective and neuroprotective effects of coconut. Numerous clinical trials have proven the anti-obesity and hypoglycemic effects of coconut oil and products. High contents of myocardial anti-oxidants, and differential metabolism of medium chain fatty acids (MCFAs) provide cardioprotective effects. The ketogenic effect of coconut derived products confers neuroprotective measures and enhanced energy expenditure in the metabolism of MCFAs and polyphenolic anti-oxidants are suggested to offer anti-obesity effects. Nevertheless, further research with more randomized, controlled, large clinical trials that evaluate the optimal dosage and side effects, if any, are warranted. Based on this comprehensive review, it is understood that MCFAs are the key component, apart from the phytochemicals such as polyphenols, tocopherols, and other antioxidants that accord these health benefits. Overall, the health benefits of coconut and its derivatives are perceptible, though there is a need for long-term clinical trials. Also a shift of research focus from coconut fatty acids and oil to other phytochemicals and to design appropriate clinical and epidemiological studies to discover coconut biomolecules of health importance is warranted.