О сновные проблемы, на решение которых направлены усилия современной селекцииэто полноценное питание людей, их здоровье, источники энергии. В России значительную долю среди овощей составляют растения семейства Тыквенные (Cucurbitaceae). Наибольшее хозяйственное значение среди них имеют огурец, тыква, кабачок, патиссон, дыня и арбуз. Плоды этих культур отличаются высокими вкусовыми и целебными свойствами. Их выращивают во всех регионах России, как в открытом, так и защищенном грунте. В условиях современного рынка потребительский спрос на овощную продукцию постоянно растет и меняется. Это создает необходимость наличия у селекционера генотипически раз-нообразного и стабильного материала, который позволит быстро удовлетворять требования современного производства. В мировой практике широкое распространение имеют гибриды F 1 , которые отличаются от сортов высокой выравненностью и урожайностью, а также способствуют защите прав селекционеров и семеноводов. Создание гибридов требует использования

Relevance. The development of F1 hybrids distinguishing it from cultivars by high productivity, plant uniformity in ripening date, fruit sizes and quality is the promising trend in breeding program in cucumber (Cucumis sativus L.).The aim of the study was to optimize the gynogenesis induction condition in culture of unpollinated ovules in vitro in order to broad the generation of new breeding forms and to accelerate homozygous line production.Materials and methods. Eight promising cucumber accessions from Laboratory of Cucurbit Breeding and Seed Production (FSBSI FSVC) were taken for the study. The protocol developed in Laboratory of Biotechnology (FSBSI FSVC) for production of doubled haploid in Cucurbitaceae family was used in the experiment. The medium IMC with 30 g/L sucrose and 7g/L agar supplemented with 200 mg/L ampicillin and 0.2 mg/L thidiazuron (TDZ) was applied to induce gynogenic development.Results. The half-open bud or flower was shown to be the most suitable to be taken as an explant for cultivation. Highest number of embryo-like structures in all accessions developed from ovaries 2.1-2.6 cm long. Exposure to sterilization solution of sodium hypochlorite for 15 min made ovary wall softer and ovules can be then easily extracted without traumatizing. The traumatized ovule resulted in inhibited gynogenic development. Embryoids and calli had developed in all studied cucumber accessions, but well-formed plants were only obtained in six accessions. In total 26 plants were produced. The maximum gynogenesis induction equal to 63.1% was achieved in accession 1810. Maximum number of plant produced was twelve in accession 1763, but the greatest plant outcome 7.7% of the ovules with induced gynogenesis was observed in accession 1807.

Plants have evolved a complex multilayered defense system to counteract various invading pathogens during their life cycle. In addition to silencing, considered to be a major molecular defense response against viruses, different signaling pathways activated by phytohormones trigger the expression of secondary metabolites and proteins preventing virus entry and propagation. In this study, we explored the response of cucumber plants to one of the global pathogens, cucumber green mottle mosaic virus (CGMMV), which causes severe symptoms on leaves and fruits. The inbred line of Cucumis sativus L., which is highly susceptible to CGMMV, was chosen for inoculation. Transcriptomes of infected plants at the early and late stages of infection were analyzed in comparison with the corresponding transcriptomes of healthy plants using RNA-seq. The changes in the signaling pathways of ethylene and salicylic and jasmonic acids, as well as the differences in silencing response and expression of pathogenesis-related proteins and transcription factors, were revealed. The results show that silencing was strongly suppressed in infected plants, while the salicylic acid and ethylene signaling pathways were induced. The genes encoding pathogenesis-related proteins and the genes involved in the jasmonic acid pathway changed their expression insignificantly. It was also found that WRKY and NAC were the most sensitive to CGMMV infection among the transcription factors detected.

Relevance. Pumpkin is one of the most important source of carotenoids for humans: β- and α-carotene, lutein and zeaxanthin playing a fundamental role in providing twilight and color vision accordingly.Results. Investigation of pumpkin carotenoid composition, Konfetka variety, revealed for the first time that this cultivar is the only one containing exclusively lutein in pulp with lutein and zeaxanthin in peel and lutein, zeaxanthin and β-carotene in placenta. Lutein concentration in pulp reached 11 mg/100 g, peel – 41.3/100 g, placenta – 51.2 mg/100 g. Zeaxanthin was absent in pulp and reached 28.3 mg/100 g in peel, and 10 mg/100 g in placenta. β-Carotene was detected only in placenta where its concentration was as much as 94.7 mg/100 g. The results indicate great prospects of ‘Konfetka’ components utilization (pulp, peel, placenta) in food industry, production of baby food and biologically active food additives, containing lutein and zeaxanthin.

The culture of unpollinated ovules in vitro in summer squash was used to develop fully homozygous breeding lines with the aim of the speeding-up breeding program. As a result of assessment for economically valuable traits, the seven promising DH-lines obtained from summer squash accessions differed by fruit shapes and colours were selected out. All breeding lines produced showed high homogeneity that retained in following generations and also have an appropriate set of economically valuable traits. DH-lines belonging to female type have up to 96% female flowers and only 4% male flowers. It is very important for breeding when the male flowers appeared in two weeks just after the female flower began blooming. The development of morphologically abnormal female and male flowers, along with gynandromorphy flowers was noted on selected DH-lines. During vegetation period from 26 to 36 flowers appeared on the plant, where out of them 19-21 ones were normally developed female flowers, 3-5 ones were normally developed male flowers, and up to 10-11 ones showed an abnormal way of development. The percentage of abnormal flowers stayed invariable when growing in greenhouse condition with high humidity and temperature as well as in open field condition. As it was shown the development of deformed abnormal flowers inherited and manifested in the following generation after self-pollination. As a result of the study, the occurred anomalies in course of male and female flower development in summer squash (C. pepo L.,) DH-lines produced through a cultivation of unpollinated ovules in vitro were described in details for the first time.