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Item Analysis of segregating populations of West Coast Tall variety of coconut using microsatellite markers(2006) Manimekalai, R.; Rubavathi, V.B.; Thomas Regi, J.; Nair, R.V.; Rajesh, M.K.In vitro antagonistic studies with native Trichoderma spp viz., T.viride, T.harzianum & T.hamatum and a bacterial strain of Pseudomonas fluorescens revealed that the mycelial growth of the coconut pathogens viz., Ganoderma applanatum and G.lucidum (basal stem rot pathogens) and Thielaviopsis paradoxa (stem bleeding pathogen) was highly inhibited by T.viride (more then 80%). Pseudomonas fluorescens completely inhibited the growth of both the species of Ganoderma, whereas only 33% inhibition was observed in the growth of T.paradoxa. All the three species ofTrichoderma were found to be very effective in producing specific volatile met.abolites against T.paradoxa. The volatile metabolites of P.fluorescens completely inhibited G.applanatum and Glucidum but non-volatile metabolites were not effective. Application of 50 g of talc formulation of Trichoderma viride or T.harzianum or T.hamatum with combination of5 kg neem cake/palm/year in basins around the palm was found to be effective in the management ofbasal stem rot disease and smearing oftalc powder paste ofTrichoderma viride or T.harzianum or T.hamatum reduced bleeding patches due to stem bleeding disease. Developed a common biointensive "10M package against basal stem rot and stem bleeding diseases.Item An analysis of World Coconut Situation(Indian Coconut Journal, 1998) Jacob MathewItem Anatomical changes in the tissues of the tender leaves of coconut palms affected by the root (wilt) disease(2007-02-08) Thomas Joseph; Shanta, P.Item And now, a new biofertilizer(2007-02-08) Ghai, S.K.; George V. ThomasItem An annotated bibliography on Rhynchophorus ferrugineus - A pest of coconut(2007-02-08) Thajudin, S.Item Another invasive pest, coconut leaf beetle, Brontispa longissima (Gestro), an imminent biosecurity threat at the doorsteps of India(2012-08) Rajan, P.; Nair, C.P.R.; Josephrajkumar, A.; Chandrika MohanItem 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 Anthesis and anther dehiscence of cashew flower(2007-02-08) Mohan, K.V.J.; Kumaran, P.M.; Murthy, K.N.; Nayar, N.M.Round the clock observations on anthesis were made for five consecutive days in three periods of flowering viz., early December, mid-February, and late April. The peak period of anthesis of male flower was around 6 b and the same for bisexual flower was around 11 h. The time taken for anther to dehisce with respect to flowers opened at different hours starting from 6 h was recorded. The time required for dehiscence reduced linearly as the day advanced.Item Anthesis and pollen studies in nutmeg Myristica fragrans houtt(2007-02-08) Bavappa, K.V.A.; Heen Banda, Y.M.A study of anthesis and pollen viability in nutmeg showed that anthesis started at 3 a. m. and continued upto 5 a. m. The anther dehiscence was observed to take place about 36 hr. in advance of the anthesis between 9 a. m. and 2 p. m. The pollen grains so held inside the flower were released as a cloud at the time of anthesis. The male flowers were shed in about 36 hr. after anthesis. The pollen had a mean diameter of 48.8/1, non-sticky, pilated in sculpture, spherical in shape and without any aperture. No insects were observed to visit the flowers at the time of anthesis. Of the different concentrations of sucrose tested, maximum pollen germination of 74.3% was recorded in 5% sucrose solution. Pollen tube growth was also maximum in this concentration. Pollen germination was observed to start 2 hr. after the dusting of the pollen into the medium and was complete in about 5 hr. The mean stainability of pollen was 96.9%.Item Antifungal activity of some plant extracts against ganoderma lucidum (curtis ex.fr.) karst., causing basal stem rot disease in arecanut(2014) Chakrabarty, R.; Acharya, G.C.; Sarma, T.C.Basal stem rot disease caused by the fungus, Ganoderma lucidum (Curtis Ex. Fr.) Karst, is the most dreaded disease of arecanut in Assam. The experiment was carried out to test the antifungal activity of aqueous extract of thirty locally available plant species against the test fungus. Pure culture of Ganoderma sp. was isolated from fruiting body of infected arecanut palm. Among the plant species tested, Allium sativum corm extract exerted maximum inhibition with 90.89, 100 and 100 per cent inhibition over control at 5, 10 and 20 per cent conc. respectively, followed by extract of Solanum nigrum with 77.00. 84.11 and 100 per cent inhibition over control at 5, 10 and 20 per cent conc. respectively after 144h of incubation. Leaf extract of Clerodendron infortunatum, Bidens pilosa, Leucas aspera, Spilanthes paniculata, Lawsonia inermis and Cinnamomum verum showed strong inhibitory effect at 20 per cent conc. with 84.00, 83.88, 79.22, 77.22, 76.11 and 72.78 per cent inhibition over control respectively.Item Antimicrobial activities of polyphenol extract of arecanut against pathogenic bacteria(2012) Senthil Amudhan, M.Item Antioxidant activity and biochemical profile of cocoa clones(2016) Senthil Amudhan, M.; Elain Apshara, S.Item Apomixis in Areca triandra Roxb.(2007-02-08) Bavappa, K.V.A.; Nair, M.K.Considerable morphological differences were observed in reciprocal hybrids involving A. catechu and A.triandra. While A. catechu x A.triandra hybrids were intermediate for some characters, showed heterosis and dominance for certain other characters, and were highly sterile, A. triandra x A. catechu plants were almost similar to A. triandra and did not indicate any evidence of hybridity. Based on these and the failure of A. catechu pollen to germinate on stigmatic surface of A. triandra, the latter species is inferred to be apomictic. This is further supported by the occurrence of limited extent of meiotic irregularities, reduced pollen fertility, low quantity of pollen and nut set obtained without pollination. It has been inferred that apomixis in A.triandra is autonomous.Item Application of nonparametric additive model for input-response analysis in arecanut(Indian Society for Plantation Crops, 2008) Jose, C.T.; Ravi BhatThe relationships between the inputs and response are very complex in crop production models. Problems like nonlinear relationships between inputs and responses, nonexistence of proper functional form to represent relationship between inputs and response variable and multi-collinearity are very common in crop production data. The traditional multiple linear regression technique may not be adequate in many situations to explain input output relationship. In this paper we have used nonparametric additive regression model to explain input output relationship in arecanut. The comparative study shows that the nonparametric additive modeling technique performed much better than the multiple linear regression technique to explain the input response relationship. The estimated values of the component functions provide the mean response of input variables on the yield of arecanut. The optimum value of the input variables is obtained from the graphical representation of the component functions. The present analysis of data from the two districts show that input response relationship vary depending on the agro-climatic conditions of the locations.Item Application of nonparametric covariance analysis in field trial with reference to YLD management trial in arecanut(Indian Society for Plantation Crops, 2008-05) Jose, C.T.; Saraswathy, N.Item Application of RAPD markers in hybrid verification in coconut(2014) Rajesh, M.K.; Jerard, B.A.; Preethi, P.; Regi Jacob Thomas; Anitha KarunCoconut palms are classified into two major types, viz., ‘talls’ and ‘dwarfs’, which mainly differ in their pollination behavior of cross- and self-pollination, respectively. Due to this difference, getting true-to-type progenies of desirable tall and dwarf cultivars has always been a challenge. The conventional practice of selection of seedlings based solely on morphological traits often results in selection of out-crossed seedlings and undesirable off-types. In the present investigation, RAPD markers for the tall/dwarf trait were identified in coconut using a bulked DNA approach. Screening of tall and dwarf palm bulk DNA with 200 primers revealed a RAPD primer OPBA3 which was able to clearly differentiate both the tall and dwarf bulks. For validation, the primer was used to screen individual tall and dwarf coconut palms representing different geographic regions. The primer was also used to screen the parents and validate hybrids of Dwarf x Tall crosses.Item Application of satellite imagery to identify vegetation types - a case study on coconut(JPC, 2004-12) Utpala Parthasarathy; Kumaran, P.M.; Das, M.M.Remote sensing data stored in digital tapes of images can be interpreted by employing computers which can process spectral reflectance properties of objects, every pixel, using fundamental statistical pattern recognition technique. In the present study Satellite imagery of the Kasaragod district of Kerala amid Kamrup district of Assam were used to study coconut area. A cropping pattern map has been drawn for coconut and other important crops of the districts. It is noticed that in case or Kasaragod, which has a vast coconut cultivation it is very easy to identify it in the imagery, but in the case of Kamrup where the cultivation is only in homestead, the identification is not easy in 1:50,000 scale. A data with higher resolution can solve the problem.Item An applicator for filling granular insecticides into the leaf axils of Arecanut Palms(2007-02-08) Abraham, V.A.