APPLICATION OF NEW METHOD OF ARTIFICIAL INCUBATION OF SEVAN TROUT (SALMO ISCHCHAN, KESSLER) EGGS IN NATURAL CONDITION OF TRIBUTARIES OF LAKE SEVAN

Endemic fish species of Armenian ichthyofauna – the Sevan trout (Salmo ischchan, Kessler, 1877) is registered in the Red Book of Animals of the Republic of Armenia as critically endangered (corresponds to IUCN category: CR A2cd). Its natural reproduction hardly occurs as a result of numerous problems related to the use and management of water and bio-resources in the drainage basin of Lake Sevan. The Lichq River is formerly known as a spawning river for two ecological races of Sevan trout, but because of different factors there are no more wild populations of Sevan trout spawning. The aim of the study was checking the efficiency of two methods of egg incubation in the Lichq River for restoration of Gegarkuni population. The experiments were carried out with newly fertilized and eyed eggs of Gegarkuni in the same periods and in the same areas to avoid the unforeseen effects of environmental factors on assessment. The results showed that the mortality rate of green eggs in the natural conditions is quite high before reaching eyed egg stage (65-68%), while the mortality rate of eyed eggs planted in the natural conditions is only 9-17%. This means that the effectiveness of planting eyed eggs is higher for the artificial restoration of Gegarkuni stocks in the nature.

Genome-Wide Assessment of Avocado Germplasm Determined from Specific Length Amplified Fragment Sequencing and Transcriptomes: Population Structure, Genetic Diversity, Identification, and Application of Race-Specific Markers

Genomic data is a powerful tool. However, the phylogenetic relationships among different ecological races of avocado remain unclear. Here, we used the results from specific length amplified fragment sequencing (SLAF-seq) and transcriptome data to infer the population structure and genetic diversity of 21 avocado cultivars and reconstructed the phylogeny of three ecological races and two interracial hybrids. The results of the three analyses performed (unweighted pair-group methods with arithmetic means (UPGMA) cluster, Principal coordinate analysis (PCoA), and STRUCTURE) based on single nucleotide polymorphisms (SNPs) from SLAF-seq all indicated the existence of two populations based on botanical race: Mexican–Guatemalan and West Indian genotype populations. Our results based on SNPs from SLAF-seq indicated that the Mexican and Guatemalan races were more closely related to each other than either was to the West Indian race, which also was confirmed in the UPGMA cluster results based on SNPs from transcriptomic data. SNPs from SLAF-seq provided strong evidence that the Guatemalan, Mexican, and Guatemalan × Mexican hybrid accession possessed higher genetic diversity than the West Indian races and Guatemalan × West Indian hybrid accessions. Six race-specific Kompetitive allele specific PCR (KASP) markers based on SNPs from SLAF-seq were then developed and validated.

The concept of species in poplars (genus Populus L., Salicaceae) based on the example of the subgenus Tacamahaca (Spach) Penjkovsky representatives growing in Russia and neighbouring countries

Using the traditional research methods, based on the example of local and cultivated representatives of the Tacamahaca (Spach) Penjkovsky subgenus growing in Russia and neighboring countries, the concept of a species in poplars (genus Populus L., Salicaceae) has been developed. It is suggested that the sections of black poplars (Aigeiros Duby) and balsamic poplars (Tacamahaca Spach) in Eurasia form a single supraspecific system with a common gene pool, which is very similar to syngameon. The taxonomic species that make up such a system are different dynamic states of this system and exist in the equilibrium state between natural selection, which forms and preserves the specifics of each dynamic state, and gene flows from other taxonomic species. Such a system can also be considered as a large Linnaean species represented by many subspecies or even geographical and ecological races. The use of molecular genetic methods for the taxonomic species study in the Populus genus is difficult due to the powerful flow of genes between the species, since the species differ in a small number of genes responsible for adaptive characters. The sections of the subgenus Tacamahaca poplars are ecological. The combination of species in these sections is not so much about the unity of their origin, but about the common growing conditions: black poplars tend to grow in lowlands, while the balsamic poplars tend to grow in the mountains, with which the poplars’ diagnostic characters are associated. In nature, belonging to a certain section is more profitable than the intermediate state, but in cultivation and in the urban environment, the opposite situation is observed.

MITOCHONDRIAL DNA VARIATIO OF THE RICE YELLOW STEM BORER, Scirpophaga incertulas, (LEPIDOPTERA: CRAMBIDAE) IN JAVA, INDONESIA

Scirpophaga incertulas is one of economically important rice pests in South East Asia, including Indonesia. Systematic investigation on biological characteristics of ecological races based on recently changed of agricultural practiced and environment has been conducted in order to asses knowledge on genetic variation of population of S. incertulas in Indonesia. A 685 bp segment of mitochondrialDNA COII was amplified from 42 different yellow stem borer samples from five locations in Java. The objectives of this study were to generate mitochondrial CO II  sequences for all available yellow stem borer  samples and to define haplotypes and nucleotide sequence diversity of the different yellow stem borer populations. Six different haplotypes (YSB1, YSB2, YSB3, YSB4, YSB5 and YSB6) were identified in yellow stem borer populations. The majority of the sampled individuals caried haplotype YSB2. Overall, the results of Tajima’s test statistic indicated that the population of Java was D= 0.85201, which suggests that there was no indicative of purifying selection or there was no presence of deleterious mutation segregating in the population. However, the results were not significant (P> 0:10) and additional studies are required to confirm this finding.Key words: Scirpophaga incertulas, yellow stem borer, MitochondrialDNA COIIÂ

Hybridization, ecological races and the nature of species: empirical evidence for the ease of speciation

Species are generally viewed by evolutionists as ‘real’ distinct entities in nature, making speciation appear difficult. Charles Darwin had originally promoted a very different uniformitarian view that biological species were continuous with ‘varieties’ below the level of species and became distinguishable from them only when divergent natural selection led to gaps in the distribution of morphology. This Darwinian view on species came under immediate attack, and the consensus among evolutionary biologists today appears to side more with the ideas of Ernst Mayr and Theodosius Dobzhansky, who argued 70 years ago that Darwin was wrong about species. Here, I show how recent genetic studies of supposedly well-behaved animals, such as insects and vertebrates, including our own species, have supported the existence of the Darwinian continuum between varieties and species. Below the level of species, there are well-defined ecological races, while above the level of species, hybridization still occurs, and may often lead to introgression and, sometimes, hybrid speciation. This continuum is evident, not only across vast geographical regions, but also locally in sympatry. The existence of this continuum provides good evidence for gradual evolution of species from ecological races and biotypes, to hybridizing species and, ultimately, to species that no longer cross. Continuity between varieties and species not only provides an excellent argument against creationism, but also gives insight into the process of speciation. The lack of a hiatus between species and ecological races suggests that speciation may occur, perhaps frequently, in sympatry, and the abundant intermediate stages suggest that it is happening all around us. Speciation is easy!