Development of caryological and molecular-genetic investigations of wetland and dryland populations of conifers

Aim. On the basis of studies which carried out by various authors, regularities of karyotypic and genetic divergence of populations of conifers growing in wetlands and dry lands are analyzed. Methods. The karyological and molecular-genetic methods of analysis are used. Results. Data are obtained on possible ways of evolution of karyotypes, consisting in changes in the number of chromosomes, the size and morphology of chromosomes, the number of secondary constrictions in chromosomes, the spectrum of chromosome rearrangements, and the frequency of their occurrence, distinguishing wetland populations of conifers species from dry land ones. With the help of isozyme markers and markers of nuclear and cytoplasmic genomes differences in the genetic structure of conifers populations from wetlands and dry lands are revealed. Conclusions. The genotypic structure of conifers species in wetlands and dry lands, caused by different vector of natural selection in contrasting ecological conditions of growth, differs significantly, and their karyotypic and genetic differentiation corresponds to the level of populations and groups of populations. Keywords: populations of conifers, wetlands, dry lands, karyological and molecular-genetic markers.

CONTRASTING LEVELS OF GENETIC DIVERSITY AMONG POPULATIONS OF THE ENDANGERED TROPICAL PALM EUTERPE EDULIS MARTIUS

ABSTRACT Euterpe edulis is a tropical species that produces the heart of palm, an edible product of high economic importance. However, its natural populations have been severely threatened by unrestricted exploitation, along with the destruction of its natural biome, the Atlantic Rainforest in Brazil. In this work, we examined the genetic diversity status of five natural populations using isozyme markers. Despite their limitations and replacement by DNA-based markers, isozymes are codominant markers that reveal accurate estimates of genetic diversity and structure patterns, as do microsatellites. Six informative isozyme markers were used to analyze the genetic variability of populations located in different areas of the Atlantic Forest (Ombrophilous Dense Forest and Seasonal Forest), and with different degrees of perturbation. Mean genetic diversity for all populations (Ho = 0.172, for 13 loci) was considered low for a tropical species, even for the markers used. Populations from Ombrophilous Dense Forest at the very South limit of distribution of the heart of palm presented the lowest genetic variability (Ho = 0.141), which is clearly observed from the allele frequencies, and might implicate in less adaptive potential in a scenario of climate change. On the contrary, the Seasonal Forest population presented the highest diversity (Ho = 0.237). It comprises one of the largest remaining reservoirs of heart of palm and maybe of its genetic variability. The contrasting levels of genetic diversity encountered in this study rehash the constant need of monitoring and conserving the current genetic diversity of E. edulis populations, as well as exploring strategies for its breeding.

IDENTIFIKASI PENANDA ISOZIM PER-7, PER-8, DAN RAPD OB17375 PADA KELAPA GENJAH SALAK (GSK) DAN BEBERAPA HASIL SILANGANNYA DENGAN KELAPA DALAM

ABSTRACT Runtunuwu, S.D. and E.F. Lengkong. 2005. Identification of Isozyme Markers (PER-7, PER-8, and RAPD OBI7375) of Dwarf Salak Coconut (GSK) and its Tall Hibrids. Eugenia 11 (1): 8-17. The objective of this research was to identify PER-7 and PER-8 isozymes, and OB17 375 RAPD as molecular markers for resistance to NF Phytophthora disease in Genjah Salak (GSK) dwarf coconut and its several hybrids with Tall coconut at The Research Institute for Coconut and Palmae (RICP) Manado. Coconut resistance to NF Phytophthora disease was determined based on disease lesion size of inoculated coconut fruits at 7 days after inoculation. PER-7 and PER-8 isozymes marker were identified using horizontal starch gel electrophoresis, and OB17375 RAPD marker was identified based on polymerase chain reaction (PCR) using kit B number 17 primer (Operon Technologies, California). PER-7 isozyme marker could be used to select GSK x DTA (Dalam Tenga) and GSK x RLT (Rennell Tall) hybrid coconuts that resistant to NF Phytophthora disease. PER-7 isozyme without OB17375 markers (PER-7/-) could be used to select resistant GSK x WAT (West African Tall) hybrid coconut to the disease. Keywords: Isozymes, RAPD, Molecular marker, Phytophthora disease, coconut

Morphological and Isozyme Variation in Natural Populations of the Genus Medicago L. Prospected in Northern Algeria

As part of the evaluation and enhancement of genetic resources, morphological and isozyme variability within and among 169 accessions, representing 14 species of the genus Medicago L. collected in northern Algeria, was assessed using twelve quantitative traits and two enzymatic systems. Phenotype frequencies were scored in six enzyme zones to determine isozyme variability within and among populations. The data analysis resolved a high level of genetic diversity. Ten morphometric characteristics contributed to the discrimination of the species. The relationship between the collection site environment and phenotypic characteristics was also studied. Esterase (EST) enzyme system was more polymorphic than glutamate oxaloacetate transaminase (GOT) system. Were scored 2 zones with 10 bands and 21 phenotypes for GOT (glutamate oxaloacetate transaminase) and 4 zones with 22 bands and 71 phenotypes for EST (esterase) Polymorphism index and Jaccard’s genetic distances revealed the existence of a high genetic diversity within and among the studied populations. The annual species M. polymorpha presented an intraspecific polymorphism index of 0.57, which was higher than all other species indices. Clustering of the species based on isozyme markers was in agreement with taxonomic criteria and showed no significant correlation with morphological characteristics. Conservation programs should take into account the level of genetic diversity within and between populations revealed by isozyme markers.