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The process of embryogenesis in isolated microspore culture was studied in eight carrot accessions of different origin. The ½NLN-13 medium supplemented with 0.2 mg/L 2,4D and 0.2mg/L kinetin was used to induce embryogenesis. The temperature treatment was performed at 5–6 °C for three days, followed by cultivation at 25 °C in darkness. As was shown, the first embryogenesis was only observed in microspores at the late vacuolated stage when the nucleus moved from the center to one pole following the long cell axis. Depending on the nucleus position, the microspore can divide into two equal or two different sized cells. Following divisions occurred either in one of these cells or in two. However, microspores that divided into two unequal cells were morphologically different form bi-cellular pollen grain. Embryogenic divisions in bi-cellular pollen grains were not observed. First divisions began by the third day of cultivation, and continued until the globular embryoid stage that was well-seen after the fourth week of cultivation. The already-formed embryoids can develop the secondary embryoids on their surface. Depending on the genotype, up to 1000 secondary embryoids can be produced from one embryoid in the liquid MSm medium supplemented with 0.1 mg/L of kinetin for regeneration. All carrot accessions studied were split into three groups: responsive genotypes, weakly responsive genotypes, and reluctant genotypes. The highest yield was 53 initial embryoids per a 6 cm diameter petri dish. Thus, the Nantskaya 4 cultivar totally produced 256 initial embryoids, out of which 94 developed into green plantlets and 162 into albino plantlets, whereas 97 initial embryoids with 45 albino plantlets formed from them were obtained from Chantenay cultivar.

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Discrimination Between Celery Cultivars with the Use of Rapd MarkersScreening of celery cultivars with random amplified primers is a way of avoiding mistakes in distinguishing similar genotypes. Six primers showed distinct polymorphism between the studied cultivars. The number of bands varied from 7 to 13. Suitable primers generated 52 markers of which 22 were polymorphic. A similarity matrix was created using Jaccard's coefficient. The group average method was employed to construct a dendrogram. Based on RAPD marker profiles the cultivars were grouped into three clusters coinciding with the cultivated types, var. dulce (salad celery), and var. rapaceum (turnip celery), var. secalinum (cutting celery). The salad celery entries were similar to plants of turnip celery with similarity 0.73, and the distance between genotypes of cutting celery and turnip celery was 0.68. Although only 12 cultivars have been analysed, the specific product amplified with OPX1 was observed in the three studied cultivars of cutting celery.

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