Kalanchoë Breeding: Past, Present and Future

Kalanchoë cultivars rank as one of the most sold potted ornamental plants in the world. Among its key features that sustain high market interest are the long flowering period, abundance of flowers, thick and glossy leaves, easy maintenance and less water requirement compared to other potted plants. In breeding studies of Kalanchoë, plants with different flower colors such as white, cream, yellow, orange, red, pink and purple were developed. Moreover, double-flowered cultivars (comprising a large number of petals), more compact and cultivars with larger flowers were also obtained. Novel morphological characteristics are always in high demand in the market of ornamental plants. Increasing the variation in the gene pool with different species played a major role in the development of these characteristics. Nowadays, not only potted cultivars are launched but also cut flower cultivars have been developed and presented to consumers. Besides conventional breeding and interspecific hybridization, biotechnological methods, which have a promising future, are used to develop morphological characteristics of Kalanchoë.

ASSESSMENT OF ECOLOGICAL AND GENETIC DIVERSITY OF THE GENUS VIGNA SAVI USING BIOTECHNOLOGICAL METHODS - ISSR MARKERS

The world's genetic resources of plants are the main source of improving crops for decades to come. The gene pool of plants has a hidden resource of new genes, or their combinations, including - selection-important features. The study of the potential of the plant gene pool with the main biological and economic characteristics allows to expand the genetic base of crops for the successful implementation of breeding programs in various areas. The genus Vigna has about 200 species that are grown in warm regions of the planet. The centers of origin of the species are in Africa, but mung beans, urd, azuki and rice beans are of Asian origin. The collection includes 20 specimens belonging to 7 species of the genus Vigna: V. aconitifolia (Jacq.) Marechal (willow aconitolista, mott) – 3 specimens, V. angularis (Willd.) Ohwi et Ohashi (adzuki) – 4, V. radiata (L.) R. Wilczek (mash) – 4, V. umbellata (Thunb.) Ohwi et Ohashi (vigna rice) – 4, V. unguiculata (L.) Walp. (Chinese) – 5. These are mainly local varieties, about 10 % are breeding varieties and 1% are forms that grow in nature. The multifaceted use of cultivated species of the genus Vigna contributed to their spread throughout the tropical, subtropical and temperate zones of the globe. They are economically important crops in many developing countries. Geographical analysis showed that most of the samples came from the areas of world agriculture and crop formation. most samples of V. radiata, V. mungo, V. aconitifolia, V. trilobata, V. umbellata were obtained from India and Pakistan, V. angularis – from East Asia and China, V. unguiculata – East Africa (Ethiopia, Kenya), V unguiculata – from China. However, the exact place of domestication of this culture has not been established, and in numerous sources of literature can be found different opinions of scientists on the origin of cowpea and the centers of its diversity. Recently, using the methods of molecular genetics (RAPD, AFLP and others) it was confirmed that the northern part of Africa is the center of origin of the cultured, because the wild types of West Africa are closer to cultural forms than the wild types of East and South Africa. It should be noted that the species of cowpea have a significant intraspecific polymorphism. The samples showed strong variability of morphological and economically valuable features. Such a wide range of variable variability is due to the places of cultivation of samples, different environmental conditions (plains, mountains, climate). According to the results of the evaluation of the DNA polymorphism of cowpea using molecular genetic markers, it was found that the species of cowpea involved in the study are characterized by a high level of DNA polymorphism, which averaged 78.6 %. 145 loci were identified, including 31 unique, specific to a particular sample, and 31 monomorphic, characteristic of all samples. Monomorphic loci are conserved regions of DNA that indicate the common origin of the species of cowpea involved in the work, and can be used as genus and species-specific markers. Unique loci indicate genetic divergence of the studied material and can serve as markers of certain samples. The average level of intrapopulation polymorphism of cowpea DNA (37.2–93.8 %, depending on the genotype) was established, which indicates the existence of significant variability in the studied samples of cowpea. It shows a high level of genetic divergence of cowpea species and testifies in favor of the polyphyletic theory of their origin.

Development of Selection Indices for Improvement of Seed Yield and Lipid Composition in Bambara Groundnut (Vigna subterranea (L.) Verdc.)

The underutilised grain legume bambara groundnut (Vigna subterranea) has the potential to contribute significantly to nutritional security. However, the lack of commercial cultivars has hindered its wider adoption and utilisation as a food source. The development of competitive cultivars is impeded by (1) lack of systematic data describing variation in nutritional composition within the gene pool, and (2) a poor understanding of how concentrations of different nutritional components interact. In this study, we analysed seed lipid and protein concentration and lipid composition within a collection of 100 lines representing the global gene pool. Seed protein and lipid varied over twofold with a normal distribution, but no significant statistical correlation was detected between the two components. Seed lipid concentration (4.2–8.8 g/100 g) is primarily determined by the proportion of oleic acid (r2 = 0.45). Yield and composition data for a subset of 40 lines were then used to test selection parameters for high yielding, high lipid breeding lines. From five selection indices tested using 15 scenarios, an index based on the seed number, seed weight, and oleic acid yielded a > 50% expected increase in each of the mean values of seed number, pod dry weight, seed dry weight, and seed size, as well as an expected 7% increase in seed lipid concentration.

Estimation of the gene pool of the CIMMYT collection winter bread wheat on presence of the Lr 34 gene

Nowadays in Russia and in the world, the problem of improving food security is becoming more and more urgent. One of the main crops grown worldwide is winter bread wheat. Varieties resistant to main leaf diseases can produce large grain yields. Thus, the study and identification of resistance genes are of great importance. The purpose of the current work was to estimate the gene pool of winter bread wheat from the CIMMYT collection (Mexico) according to the age brown rust Lr 34 resistance gene. In the study of collection samples, there have been used such methods as DNA extraction using CTAB, PCR, electrophoresis on agarose gels. As a result of the study, there has been identified a presence of a functional allele of the Lr 34 gene in 146 winter bread wheat samples out of 411 studied ones (sets 20th IWWYT-SA, 21th IWWYT-IRR, 25th FAWWON-IRR, 25th FAWWON-SA). There have been identified three samples with a heterozygous allelic state of the Lr 34 gene. There have been identified 232 samples with the non-functional Lr 34 gene allele. 30 winter bread wheat samples had no amplification of DNA fragments with the molecular marker csLV34, which means a significant microsatellite sequence variability for which the molecular marker was developed in their genotype. 121 out of 146 winter bread wheat samples with the functional brown rust Lr 34 resistance gene showed resistance in field conditions and in the infectious plots. The rest 25 samples with the Lr 34 gene belonged to the group of moderately resistant ones in the infectious plots. The identified 121 CIMMYT collection winter bread wheat varieties, with the Lr 34 gene possessing a resistant type of pathogen damage response (for example, 9919, 9921, 9928, 9809, 9811, 9812, 23, 24, 30, 262, 265, 266, etc.) have been recommended for use in leaf rust resistance pyramiding in future breeding programs.

Characterizing the Core Internal Gene Pool of H9N2 Responsible for Continuous Reassortment With Other Influenza A Viruses

Reassortment among avian influenza viruses is the main source of novel avian influenza virus subtypes. Studies have shown that the H9N2 virus often donates internal segments to generate novel reassortant avian influenza viruses, acting as a reassortment template. However, the characteristics of the internal pattern of reassortment remain unclear. In this article, we first defined the core gene pool of the internal segments of the H9N2 virus that provide templates for reassortment. We used genetic distance and sequence similarity to define typical clusters in the core gene pool. Then, we analyzed the phylogenetic relationships, feature vector distances, geographic distributions and mutation sites of strains related to the core gene pool. Strains in the same typical clusters have close phylogenetic relationships and feature vector distances. We also found that these typical clusters can be divided into three categories according to their main geographic distribution area. Furthermore, typical clusters in the same geographic area contain some common mutation patterns. Our results suggest that typical clusters in the core gene pool affect the reassortment events of the H9N2 virus in many respects, such as geographic distribution and amino acid mutation sites.

MODERN VIEWS ON THE СLINIC-GENETIC ASPECTS OF POLYHYDRAMNIOS.

The article analyzes the literature data on the etiopathogenetic aspects of polyhydramnios, taking into account the leading risk factors for development. Despite the knowledge of the etiological aspects, the development of diagnostic tactics and predictive methods, the frequency of polyhydramnios does not tend to decrease, but remains at the level of 3-12% of the total number of births. Being a leading medical and social problem, which leads to high childhood morbidity, disability, as well as death, negatively affecting the quality of life not only of a single family, but also on the gene pool of the nation.

Molecular characterization and genetic diversity studies of Indian soybean (Glycine max (L.) Merr.) cultivars using SSR markers

Background The genetic base of soybean cultivars in India has been reported to be extremely narrow, due to repeated use of few selected and elite genotypes as parents in the breeding programmes. This ultimately led to the reduction of genetic variability among existing soybean cultivars and stagnation in crop yield. Thus in order to enhance production and productivity of soybean, broadening of genetic base and exploring untapped valuable genetic diversity has become quite indispensable. This could be successfully accomplished through molecular characterization of soybean genotypes using various DNA based markers. Hence, an attempt was made to study the molecular divergence and relatedness among 29 genotypes of soybean using SSR markers. Methods and results A total of 35 SSR primers were deployed to study the genetic divergence among 29 genotypes of soybean. Among them, 14 primer pairs were found to be polymorphic producing a total of 34 polymorphic alleles; and the allele number for each locus ranged from two to four with an average of 2.43 alleles per primer pair. Polymorphic information content (PIC) values of SSRs ranged from 0.064 to 0.689 with an average of 0.331. The dendrogram constructed based on dissimilarity indices clustered the 29 genotypes into two major groups and four sub-groups. Similarly, principal coordinate analysis grouped the genotypes into four major groups that exactly corresponded to the clustering of genotypes among four sub-groups of dendrogram. Besides, the study has reported eight unique and two rare alleles that could be potentially utilized for genetic purity analysis and cultivar identification in soybean. Conclusion In the present investigation, two major clusters were reported and grouping of large number of genotypes in each cluster indicated high degree of genetic resemblance and narrow genetic base among the genotypes used in the study. With respect to the primers used in the study, the values of PIC and other related parameters revealed that the selected SSR markers are moderately informative and could be potentially utilized for diversity analysis of soybean. The clustering pattern of dendrogram constructed based on SSR loci profile displayed good agreement with the cultivar’s pedigree information. High level of genetic similarity observed among the genotypes from the present study necessitates the inclusion of wild relatives, land races and traditional cultivars in future soybean breeding programmes to widen the crop gene pool. Thus, hybridization among diverse gene pool could result in more heterotic combinations ultimately enhancing genetic gain, crop yield and resistance to various stress factors.

Uncrowded Hypervolume-based Multi-objective Optimization with Gene-pool Optimal Mixing

Domination-based multi-objective (MO) evolutionary algorithms (EAs) are today arguably the most frequently used type of MOEA. These methods however stagnate when the majority of the population becomes non-dominated, preventing further convergence to the Pareto set. Hypervolume-based MO optimization has shown promising results to overcome this. Direct use of the hypervolume however results in no selection pressure for dominated solutions. The recently introduced Sofomore framework overcomes this by solving multiple interleaved single-objective dynamic problems that iteratively improve a single approximation set, based on the uncrowded hypervolume improvement (UHVI). It thereby however loses many advantages of population-based MO optimization, such as handling multimodality. Here, we reformulate the UHVI as a quality measure for approximation sets, called the uncrowded hypervolume (UHV), which can be used to directly solve MO optimization problems with a single-objective optimizer. We use the state-of-the-art gene-pool optimal mixing evolutionary algorithm (GOMEA) that is capable of efficiently exploiting the intrinsically available greybox properties of this problem. The resulting algorithm, UHV-GOMEA, is compared to Sofomore equipped with GOMEA, and the domination-based MO-GOMEA. In doing so, we investigate in which scenarios either domination-based or hypervolume-based methods are preferred. Finally, we construct a simple hybrid approach that combines MO-GOMEA with UHV-GOMEA and outperforms both.

Albinism in F1 Hybrids Hinders Geneflow Between Cultivated Chickpea (Cicer arietinum L.) and the Tertiary Gene Pool Species, Cicer Pinnatifidum

Wild Cicer species, especially those in the tertiary gene pool, carry useful alleles for chickpea improvement. The aim of this study was to evaluate the crossability and geneflow between three chickpea cultivars (as female parents) and four cross-incompatible Cicer pinnatifidum accessions (as pollen parents) from the tertiary gene pool. Ten crosses were conducted. One fully developed healthy F1 seed was harvested in vivo from the ICC 4958 × ICC 17269 cross, but the seedling developed an albino phenotype at 4–5 days after germination. Unlike other crosses, those involving the cultivar ICCV 96030 generated a large number of pods with comparatively large ovules. One albino plantlet was obtained from the ICCV 96030 × ICC 17269 cross by embryo rescue. Crosses involving ICCV 10 resulted in flower drop and poor pod set. These variable genotype-specific responses of pod, ovule, and seed development indicate that genetic factors affect the formation of interspecific hybrids. Although pod and seed formation in these interspecific crosses can be improved, geneflow between these materials is hindered by a strong genetic factor conferring albinism in the F1 hybrids.