Browsing by Author "Parthasarathy, V.A."

Now showing 1 - 20 of 59
  • Thumbnail Image
    Item
    Allozyme variation in populations of dwarf coconut cultivars
    (2004) Geethalakshmi, P.; Niral, V.; Parthasarathy, V.A.
    Six dwarf coconut cultivars viz., COD, MYD, CGD, MOD, GDD and GBGD were studied for isozyme polymorphism using seven enzyme systems - EST, PER, PPO, MDH, ACP, ADH and GOT. Among the cultivars, higher enzyme polymorphism was observed in GDD and least in GBGD. Of the seven isozyme systems, PPO showed higher polymorphism followed by EST, GOT, PER and MDH. ACP and ADH did not show any intrapopulation variation.
  • Thumbnail Image
    Item
    Analysis of coconut cultivars and hybrids using isozyme polymorphism
    (ACTA BOT CROAT, 2004) Parthasarathy, V.A.; Geethalakshmi, P.; Niral, V.
  • Thumbnail Image
    Item
    Analysis of population structure and genetic relatedness among root (wilt) disease-resistant and susceptible west coast tall coconut palms (Cocos nucifera) using microsatellite markers
    (2011-06) Devakumar, K.; Thomas, R.J.; Nair, R.V.; Augustine Jerard, B.; Rajesh, M.K.; Jacob, P.M.; Jayadev, K.; Parthasarathy, V.A.
    The population structures among the root (wilt) disease-resistant and susceptible coconut palms from 12 locations in the three disease-endemic districts of southern Kerala, were analyzed using nine microsatellite markers. The pair-wise population differentiation estimate (Fs) between the resistant and susceptible populations was 0.021. Two major populations and a subpopulation cluster were identified among the resistant palms. The analysis of genetic relatedness between the resistant mother palms showed that most of the palms located in a single locality shared sib relationship among them. The existence of close genetic relationship among resistant palms from Chengannur, Thiruvalla, Kottayam and Pavukkara localities in Kerala were reported. The results are discussed in terms of breeding strategies for increasing heterozygosity and obtaining the maximum number of disease-resistant seedlings.
  • Thumbnail Image
    Item
    Arecanut
    (Today & Tomorrow's Printers and Publishers, New Delhi -110 002, India, 2017) Ananda, K.S.; Anitha Karun; Parthasarathy, V.A.
  • Thumbnail Image
    Item
    Assessment of the genetic diversity of Indian coconut accessions and their relationship to other cultivars, using microsatellite markers
    (No. 145 Plant Genetic Resources Newsletter, 2006) Devakumar, K.; Jayadev, K.; Rajesh, M.K.; Chandrasekhar, A.; Manimekalai, R.; Kumaran, P.M.; Parthasarathy, V.A.
    Coconut cultivation in the Indian subcontinent over many centuries has given rise to diverse cultivar types, identi- fied based on discernible morphological traits, geographical locations and farmers’ choice. The Indian coconut germplasm base has also been enriched through introductions from other major coconut growing regions of the world. This study assessed the genetic diversity in a range of coconut accessions, and their relationship to other major coconut cultivars, using microsatellite markers. Microsatellite assay was used for 23 Indian accessions (15 Talls and 6 Dwarfs) and for 21 exotic accessions (18 Talls and 6 Dwarfs). A total of 48 alleles were detected in the Indian accessions by using 8 microsatellite primers (average 6 alleles per locus). More alleles were detected in the Indian accessions than in the exotics, indicating the presence of a wide allelic spectrum in the Indian accessions. Mean gene diversity ranged from 0.00 for ‘Chowghat Green Dwarf’ to 0.59 for ‘Lakshadweep Ordinary Tall’, with an overall mean of 0.32. The within-population variation was slightly higher (53%) than the betweenpopulation variation (47%), suggesting recent local adaptation and subsequent divergence among Indian cultivars. An UPGMA dendrogram separated the Indian accessions into two groups, one clustering with South-east Asian cultivars, which are introgressed types, and another clustering with African and Sri Lankan cultivars. The results are discussed in terms of diversity of Indian coconut accessions and relationships to other major coconut cultivars.
  • Thumbnail Image
    Item
    Biometric clustering of coconut populations of three Indian Ocean Islands
    (2007-02-08) Kumaran, P.M.; Koshy, P.K.; Arunachalam, V.; Niral, V.; Parthasarathy, V.A.
    Coconut populations of Indian Ocean Islands of Madagascar, Mauritius and Seychelles were clustered using principal component analysis. A total of 28 vegetative, reproductive and fruit characters were used for analysis. Floral, foliar and fruit characteristics analysis indicated the usefulness of 11 characters for clustering. Five clusters were obtained on the basis of these characters. Nut characters were also found to be good for cluster analysis. All the dwarfs were in one cluster when vegetative and nut characters were considered. While selected, characters of two tails, Comoros Tall and Coco Bleu Tall were also included along with dwarfs indicating die doubtfulness of the genetic nature of these materials. These may be in fact dwarfs erroneously recorded as tails. Cluster analysis did not show any geographical affinity within the region.
  • Thumbnail Image
    Item
    Biotechnology - Engineering plantation crops for future
    (1999) Iyer, R.D.; Parthasarathy, V.A.
  • Thumbnail Image
    Item
    Characterization of coconut germplasm based on protein polymorphism
    (2005-06) Geethalakshmi, P.; Niral, V.; Parthasarathy, V.A.
  • Thumbnail Image
    Item
    Cocoa
    (2011) Niral, V.; Rajesh, M.K.; Parthasarathy, V.A.
  • Thumbnail Image
    Item
    Cocoa
    (Today & Tomorrow's Printers and Publishers, New Delhi -110 002, India, 2017) Elain Apshara, S.; Balasimha, D.; Parthasarathy, V.A.
  • Thumbnail Image
    Item
    Coconut
    (2011) Rajesh, M.K.; Niral, V.; Anitha Karun; Parthasarathy, V.A.
  • Thumbnail Image
    Item
    Coconut
    (Naya Udyog, Kolkata., 2006-01) Rajagopal, V.; Parthasarathy, V.A.; Naresh Kumar, S.; Reddy, D.V.S.; Rohini Iyer
  • Thumbnail Image
    Item
    Coconut
    (Today & Tomorrow's Printers and Publishers, New Delhi -110002, India, 2017) Niral, V.; Rajesh, M.K.; Parthasarathy, V.A.
  • Thumbnail Image
    Item
    Coconut Biotechnology
    (2018) Rajesh, M.K; Anitha Karun; Parthasarathy, V.A.; p
  • Thumbnail Image
    Item
    Coconut community in India -a profile
    (CPCRI, 2001-09) Arulraj, S.; Rajagopal, V.; Sairam, C.V.; Thamban, C.; Anithakumari, P.; Dhanapal, R.; Bosco, S.J.D.; Subaharan, K.; Naresh Kumar, S.; George V. Thomas; Vinayaka Hegde; Kumaran, P.M.; Parthasarathy, V.A.
  • Thumbnail Image
    Item
    Coconut embryo culture - Protocol for germplasm collection
    (CPCRI, 2002-10) Anitha Karun; Parthasarathy, V.A.; Kumaran, P.M.; Iyer, R.D.; Sajini, K.K.
  • Thumbnail Image
    Item
    Coconut genetic resources - Genetic and molecular approaches
    (2007-02-08) Ratnambal, M.J.; Khumaran, P.M.; Arunachalam, V.; Niral, V.; Anuradha Upadhyay; Parthasarathy, V.A.
  • Thumbnail Image
    Item
    Coconut varietal improvement - A reflection of 50 Years of research
    (2007-02-08) Parthasarathy, V.A.; Ratnambal, M.J.; Kumaran, P.M.
  • Thumbnail Image
    Item
    Combining ability in coconut (Cocos nucifera)
    (2007-02-08) Nampoothiri, K.U.K.; Kumaran, P.M.; Jerard, B.A.; Ratnambal, M.J.; Rao, E.V.V.B.; Parthasarathy, V.A.
  • Thumbnail Image
    Item
    Correlation and path coefficient analysis in the F2 populations in coconut
    (2007) Nampoothiri, C.G.N.; Niral, V.; Parthasarathy, V.A.