Article Per Year (5 Year)
p-Index From 2021 - 2026
0
P-Index
This Author published in this journals
All Journal CORD
Lalith Perera
Unknown Affiliation
Agriculture, Biological Sciences & Forestry Library & Information Science

Published : 3 Documents Claim Missing Document
Claim Missing Document
Check
Articles

Found 3 Documents
Search

 1 
Hybrid Testing and Variety Identification of Coconut (Cocos nucifera L.) in Sri Lanka Using Microsatellite Markers Lalith Perera
International Coconut Community Journal Vol 26 No 1 (2010): CORD
Publisher : International Coconut Community

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.37833/cord.v26i1.136

Abstract

Currently, there is no reliable method for confirmation of the identity of coconut cultivars and the legitimacy of coconut hybrids. This makes serious problems in coconut breeding and seed production as the identity of coconut cultivars/hybrids can only be approximated at the very late stages of the growth based on reproductive traits owing to long juvenile period and the perennial nature of coconut. A microsatellite (SSR) marker based approach was used to develop an identification method for coconut varieties; Sri Lanka Tall, Sri Lanka Green Dwarf and Sri Lanka Yellow Dwarf, the key parents in the breeding programmes and tall x dwarf hybrids among them, using 18 coconut specific SSR primers. The validity of using yellow colour petiole as a phenotypic marker for the identification of dwarf yellow was also investigated. Two SSR primers, namely CAC20 and CNZ6 have exhibited the potential for distinguishing coconut varieties used as parents in the breeding programme and for confirming hybridity. It was revealed that yellow colour petiole is not a reliable marker for identification of dwarf yellow variety.
Origin, Domestication, Dissemination and Genetic Diversity of Coconut: DNA information Lalith Perera
International Coconut Community Journal Vol 17 No 01 (2001): CORD
Publisher : International Coconut Community

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.37833/cord.v17i01.347

Abstract

Information on origin, dissemination and levels and distribution of genetic diversity in coconuts will allow plant breeders and conservationists to select better breeding materials and formulate appropriate conservation strategies. PCR-based DNA profiling of coconut palms from Sri Lanka was initially conducted using both Amplified Fragment Length Polymorphism (AFLPs) and Microsatellites (SSRs). Thirty-nine microsatellite primers specific to coconut were developed by small insert genomic library construction. Eighteen of those primers were used to analyze the same set of Sri Lankan coconut materials. Overall, the results generated by both AFLPs and SSRs were in agreement. Most diversity was found in the tall variety (Typica) (0.92 and 0.62 for AFLPs and SSRs, respectively) rather than the intermediate (Aurantiaca) and dwarf (Nana) varieties (0.82 and 0.25 for AFLPs and SSRs, respectively). A hierarchical analysis of molecular variance (AMOVA) based on AFLP data was used to quantify and partition levels of variability between and within form components. This revealed that for the inbreeding dwarf and intermediate forms most variation was observed between rather than within forms. In contrast, the out-breeding tall forms exhibited as much variation within as between forms.
CHLOROPLAST DNA VARIATION IN COCONUT IS OPPOSITE TO ITS NUCLEAR DNA VARIATION Lalith Perera
International Coconut Community Journal Vol 18 No 02 (2002): CORD
Publisher : International Coconut Community

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.37833/cord.v18i02.359

Abstract

The pattern of world distribution of two major fruit morphotypes of coconuts has led to development of theories on origin, domestication and dissemination of coconut. Results of recent nuclear DNA analyses are in agreement with these theories with several other new insights. Compared to the plant nuclear genome however, the plant organelle genomes, the chloroplast genome and the mitochondrial genome are highly conserved and are maternally inherited in most angiosperms. Therefore, most useful information have come from regions of DNA located in organelle genome for studying phylogeny in angiosperms and for deducing historical information and evolutionary history of populations such as past migration routes and colonization dynamics. This study was aimed to determine the feasibility of developing polymorphic cytoplasmic markers, particularly the chloroplast markers. Chloroplast DNA variation of coconut from all coconut growing regions in the world assessed by both restriction digestions and physical separation of PCR products obtained with universal primers, by chloroplast microsatellites and by sequencing showed no variation. This tends to suggest that coconut may have gone through a severe cytoplasmic bottleneck and only one chloroplast type may have participated in the colonization process.
Co-Authors