Some results of the study of alfalfa and meadow clover samples created by biotechnology methods

The conditions for creating alfalfa samples MN-2 (from the Selena variety) and P-67 (from the Lugovaya variety) with increased resistance to Fusarium pathogens using the method of gamete selection are described. The method is based on the selection of gametes in vivo under the influence of a selective factor (culture filtrate) introduced into the generative organs at the early stages of their development using vacuum infiltration. The method was developed in the biotechnology department of the V.N. V.R. Williams. The accessions are included in the breeding process and are currently the accessory varieties. In order to identify differences at the genetic level between the created varieties and the original forms, a comparative analysis was carried out using 2 types of molecular markers based on the PCR method. DNA polymorphism was detected using SRAP primers, which may indicate a change in the structure of genes associated with economic and biological traits. Research is ongoing. When growing under the conditions of a selection and greenhouse complex of acid-tolerant plants of meadow clover, created using cellular technologies in vitro, the infestation by powdery mildew of 120 acid-tolerant plants was studied. No signs of damage were found in 10% of plants. The largest number of affected plants (36.7%) had a score of 3. It was found that a high infestation with powdery mildew (scores 4 and 5) significantly reduces the number of inflorescences in the bush to 83.4 and 75.7%, respectively. Therefore, in further studies to create a population of acid-tolerant plants, the genotypes of meadow clover were used without signs and with a low score of powdery mildew damage.

Identification of resistant tomato genotypesusing the gamete technologies

Relevance. High temperatures are among the environmental factors that negatively affect the development of most crops including tomatoes. Thus, important condition for the realization of potential plant productivity is the heat resistance.Methods of the gamete selection in combination with classical approaches can be used to select resistant genotypes and create initial breeding material with resistance to the temperature factor. Materials and methods.The experiments were carried out with intraspecific hybrids F4 of tomato: Elvira x Milenium, Elvira x Tomis, Elvira x Prestij, Mihaela x Milenium, Mihaela x Tomis, Mihaela x Prestij, Jubiliar х Milenium, Jubiliar x Tomis, Jubiliar x Prestij, Milenium x Elvira, Milenium x Mihaela. Plants were grown in the field. Flowers were collected, anthers were separated, pollen was isolated. Pollen was heated for 2 or 4 hours at 43°C in the experimental variants. In the control, pollen was maintained at a temperature of 26°C. Then pollen was sown and germinated on a cultural medium. The viability was determined by the length of pollen tubes.Results.A different reaction of pollen grains to temperature influence was established. The main sources of variability and their contribution to the variability of the pollen and seedling traits were determined. The temperature and genotype mainly determine the variability of the gametophyte and sporophyte. More than half of the hybrids combined high indicators of resistance of both pollen and seedlings, formed a larger number of flowers and better set fruits. Thus, tomato genotypes with good indicators of heat-resistance for applying in breeding have been identified based on a complex of methods for assessing the resistance of hybrids using gametophyte and sporophyte characteristics, as well as results of genetic-statistical analysis.

Twenty-First-Century Eugenics

Technologies available since the 1970s have enabled parents to influence the genetic makeup of their children. As the twenty-first century unfolds, emerging technologies—including gamete selection, gene editing, and in vitro gametogenesis—may allow greater control over heredity. These technologies have been criticized for involving “eugenics.” However, it is often not clear what this criticism amounts to. What is eugenics and/or why it is a bad thing? This chapter provides a conceptual analysis of “eugenics” and discusses its relevance to debates about twenty-first-century reproductive technologies. We argue for the plausibility of a broad definition of eugenics as “an attempt to improve heredity.” Whereas most common usages of reproductive genetic technologies fall under this broad definition, this alone does not entail they are morally problematic. Indeed, there will often be moral reasons to pursue eugenic aims. We conclude by discussing the types of practices that may be justified in the name of eugenics.

Nuevos híbridos de maíz (Zea mays L.) para el bajio y trópico seco mexicano: líneas recobradas por selección gamética.

The aim of this study was to improve the agronomic quality of the tropical lines AN1 and AN2 which have good combining ability; besides their germoplasm is part of a large number of commercial hybrids generated by the Instituto Mexicano del Maíz “Dr. Mario E. Castro Gil”. Eto Blancoand Blanco Dentado 2 were used as a source of gametes and crossed with AN1 and AN2, respectively. This study included recovered lines with different level of inbreeding, five dwarf single crosses and the original lines AN1 and AN2 which were used as testers. A randomized complete block design was used with two replications in each of the three locations during 1989-1990. The objectives were: 1. to select recovered lines on the bases of their combining ability and agronomic traits to generate new hybrids. 2. To determine the effectiveness of the diverse testers. The results showed that gamete selection was efficient in improving AN1 and AN2 lines for most of the traits evaluated such as grain yield, percent of fussarium on ears, except for percent of husk coverage. That recovered lines of AN1 were superior to those of AN2 lines for grain yield. A total of fifteen lines of AN1 and 7 lines of AN2 were identified using gamete selection.

Híbridos dobles de maíz formados con líneas mejoradas por selección gamética y retrocruza.

This research work includes the evaluation of 1040 double cross hybrids which were produced from single crosses improved by gamete and backcross procedures. Single hybrids were crossed with five testers. The yield trials were carried out during 1991 at Gómez Palacio, Durango, México, and the goals were as follows: 1) To evaluate the performance of double cross hybrids and 2) To determine the main agronomic traits on the observed variation. For grain yield, the double cross hybrids formed with single crosses improved by gamete selection performed better than those obtained by backross whose yields were adobe 11,6 t/ha (23% with respect to the best backcross genotype). The outstanding yields observed across the gamete procedure are probably due to the low percentage of rot ers. On the controry, the single crosses improved by backcross procedure showed early to flower, short height and had less problems ofboth root and stalk lodging. The best testers were AN258-18-19 x MLS4-1 and the AN 232 x 255- 18-19 when crossed with some single crosses yield more than 14 t/ha. It is import to mention that the outstanding grain yields were associated with values of general combining ability with the gamete selection. Finally, the multivariate analysis showed that two-thirds of the observed variation in the double cross hybrids was given by grain yield and clean grain yield, plant and ear height, male and female flowering.