Browsing by Author "Murali Gopal"
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Item Item Aflatoxin production by Aspergillus flavus isolates pathogenic to coconut insect pests(2007-02-08) Alka Gupta; Murali GopalAspergillus flavus isolated from naturally infected leaf-eating caterpillar (Opisina arenosella W.), lace bug (Stephanitis typica D.) and plant hopper (Proutista moesta Westwood), insect pests of the coconut palm, were tested for aflatoxin (AT) production by employing various media formulations. These A. flavus isolates were earlier found to be entomopathogenic in laboratory bioassays. A laboratory contaminant and four standard aflatoxigenic A. flavus isolates were also included in this study as reference strains. All A. flavus isolates were tested on seven AT detection media: coconut extract agar, coconut extract-sodium desoxycholate agar, coconut extract-ascorbic acid agar, coconut extract-Czapek Dox agar, coconut extract-milk powder agar, 10% commercial coconut milk powder agar (CCMPA) and 20% CCMPA. Only two isolates of A. flavus, originally isolated from O. arenosella and P. moesta, produced ATs. AT production was detected within 48 h of incubation and was detected continually up to 1 month. These AT-producing A. flavus isolates also produced bright yellow pigmentation in the medium. Of all the seven media used for AT detection, CCMPA (10%) was found to be the best one, followed by 20% CCMPA, for direct and rapid AT detection. AT production was not necessary for pathogenicity in the insects.Item Allelopathic effects of root and leaf leachates of coconut on selected beneficial microorganisms from coconut rhizosphere(Allelopathic Journal, 2006) Murali Gopal; Alka Gupta; Sunil, E.; George V. ThomasItem Amplification of Plant Beneficial Microbial Communities During Conversion of Coconut Leaf Substrate to Vermicompost by Eudrilus sp.(2009) Murali Gopal; Alka Gupta; Sunil, E.; George V. ThomasThe population densities of 15 microbial communities in the coconut leaves ? cow manure mixture (10:1 ratio, w/w) and pure cow manure, gut contents of the earthworm, Eudrilus sp., reared on the above substrates and vermicompost produced by the worm were studied. The enumeration was done by dilution plate and most probable number method using several selective and semi-selective microbial media. In the vermicompost produced from coconut leaves ? cow manure (CLV) mixture, 9 out of 15 microbial communities, particularly the plant beneficial ones, were amplified whereas five communities were amplified in case of pure cow manure (CMV). The CLV contained significantly high population of fungi, free-living nitrogen fixers, phosphate solubilizers, fluorescent pseudomonads, and silicate solubilizers. The CMV was preponderant with aerobic heterotrophic bacteria, actinomycetes, and Trichoderma spp. Spore formers were present in similar numbers in both the vermicomposts. Presence of Azotobacter was detected only in CMV. The results obtained in this study suggest coconut leaf litter to be a good alternative for cow manure for the production of vermicompost, especially in the areas where coconut is grown in plenty.Item Antagonistic activity of coconut rhizospheric and endophytic Bacillus spp. against Ganoderma applanatum and Thielaviopsis paradoxa(2011) Priya George; Alka Gupta; Murali Gopal; Chandra Mohanan, R.; Litty Thomas; George V. ThomasA screening study was carried out to detect the antagonistic potential of Bacillus spp. against Ganoderma applanatum and Thielaviopsis paradoxa, fungal pathogens of coconut. A total of 327 heat resistant, endospore producing bacilli were isolated from the rhizospheric soil and roots of coconut growing in Kerala, Tamil Nadu, Karnataka, Andhra Pradesh and Maharashtra. All the isolates were tested for antifungal activity against G. applanatum and T. paradoxa by dual cultural technique on nutrient agar medium. The zone of inhibition was measured and percentage of inhibition was calculated. More than 90 % of the rhizospheric and root endophytic isolates were found to effectively inhibit the mycelial growth of G. applanatum, with a maximum inhibition zone of 12 mm and percentage inhibition ranging from 44 to 91. About 86 % of the isolates inhibited the mycelial growth of T. paradoxa, with a maximum inhibition zone of 14 mm and percentage inhibition ranging from 42 to 93. Further tests of potent antagonists revealed that more than one mode of mechanisms like production of chitinase, siderophores, HCN, antibiotics, ammonia, β-1,3- glucanase and salicylic acid may be involved in the antagonistic activities. The results of this study revealed 13 Bacillus spp. having potential for use as biocontrol agents against G. applanatum and T. paradoxa, fungal pathogens of coconut.Item Autochthonous nutrient recycling driven by soil microbiota could be sustaining high coconut productivity in Lakshadweep Islands sans external fertilizer application(2022) Murali Gopal; Alka Gupta; Arunachalam, V.; Maheswarappa, H.P.; George V. Thomas; P. M. JacobItem Baculovirus oryctes for controlling rhinoceros beetle of coconut palm(2007-02-08) Murali Gopal; Alka GuptaItem Basidiomycete (Pseudolagarobasidium acaciicola) in coconut (Cocos nucifera) suspension culture – a report.(2023) Neema, M.; Alka Gupta; Murali Gopal; Anitha KarunItem Bespoke microbiome therapy to manage plant diseases(2013-12) Murali Gopal; Alka Gupta; George V. ThomasItem Biochars produced from coconut palm biomass residues can aid regenerative agriculture by improving soil properties and plant yield in humid tropics(2021) Murali Gopal; Alka Gupta; K. Shahul Hameed; Neenu, S; T. H. Khadeejath Rajeela; George V. ThomasItem Bioinoculant preparation simplified for farmers: 'produce and use' on-farm system(2018-12) Murali Gopal; Alka GuptaItem Biological Control of Pests of Coconut(2000) Pillai, G.B.; Antony, J.; Mohan, K.S.; Mariamma Daniel; Devasahayam, S.; Sathiamma, B.; Dangar, T.K.; Ramachandran, C.P.; Abraham, V.A.; Bhat, S.K.; Sreekumar, K.R.; Sukumaran, A.S.; Chandrika Mohan; Murali Gopal; Sosamma, V.K.; Gulsar Banu, J.Item Biological suppression of coconut pests(1999-05) Sathiamma, B.; Chandrika Mohan; Murali Gopal; Abraham, V.A.; Radhakrishnan Nair, C.P.Item Building plant microbiome vault: a future biotechnological resource(2019) Murali Gopal; Alka GuptaItem Changes in structure and function of bacterial communities during coconut leaf vermicomposting(2017) Murali Gopal; Shrikant S. Bhute; Alka Gupta; Prabhu, S. R.; George V. Thomas; William B. Whitman; Kamlesh JangidItem Co-composting of coconut coir pith with solid poultry manure(2013-01-25) George V. Thomas; Palaniswami, C.; Prabhu, S.R.; Murali Gopal; Alka GuptaItem Coconut Based Farming System: A Gandhia harmony of diverse crops, livestock and soil microorganisms(2020-10) Murali Gopal; Alka Gupta; Subramanian, P.; Anitha KarunItem Coconut Leaf Vermiwash as a Component of Organic Farming for Sustaining Soil Health and Fertility(2012) Murali Gopal; Alka Gupta; George V. ThomasVermiwash, produced from actively vermicomposting substrates of coconut leaf + cowdung by the action of Eudrilus sp., has an alkaline pH, contains major and minor nutrients, growth hormones, humic acid and plant beneficial bacteria. Application of appropriately diluted coconut leaf vermiwash has shown to increase germination and seedling vigour index of cow pea and paddy seeds in laboratory bioassays. Field trials with cowpea, maize and. bhendi (okra) in CPCRI farm showed its capacity 1.0 increase biomass and yield of the crops accompanied by enhanced soil microbial activities. Application of the vermiwash in red sandy loam soil produced an increase of 36% of fresh biomass weight, nodule numbers and 43% nodule fresh weight in cowpea at 1: 10 dilution compared to control. In maize, increase in cob yield by 5-10%, fresh cob weight increase of 29-64% and in bhendi 22 to 33% increase in yield were recorded when vermiwash was applied at 1:5 dilution. To validate these results, field trials were taken up in farmers' plots at Majal and Edneer area in Kasaragod. Bitter gourd and cowpea crops were taken up at Majal while amaranthus, cowpea and green chillies at Edneer. The soil type was sandy loam at Majal and lateritic at Edneer. Vermiwash produced at CPCRI was used as treatment along with farmers' practice as control. The mode of application of vermiwash, dilution rates and intervals of application were carried out by the farmers as per recommendations. Observations on yield of the crops in vermiwash applied plots were recorded by the fanners. A yield of 75 kg cowpea and 200 kg bitter gourd at Majal; S5 kg amaranthus, 1 S5 kg cowpea and 10kg dried chilli at Edneer plot were recorded from vermiwash applied plots.Item Coconut Leaf Vermiwash for Soil Health Improvement and Quality Yield of Vegetable Crops -Validation in Farmers Fields(2010) Murali Gopal; Alka Gupta; Rayudu, B.T.; George V. ThomasItem Coconut leaf vermiwash: a bio-liquid from coconut leaf vermicompost for improving the crop production capacities of soil(2010) Murali Gopal; Alka Gupta; Palaniswami, C.; Dhanapal, R.; George V. Thomas