In vitro cultivation of the embryos of hybrid forms of early-ripening sweet cherry (Prunus avium L.) varieties

• Main Authors: N. N. Kovalenko, S. V. Gladkih
• Format: Article
• Language: English
• Published: Institute of Cytology and Genetics of Siberian Branch of the Russian Academy of Sciences 2019-10-01
• Series: Vavilovskij Žurnal Genetiki i Selekcii
• Subjects: sweet cherry; selection; intraspecific hibridization; embrio; nutrient medium; vitamins; phytohormones; in vitro cultivation
• Online Access: https://vavilov.elpub.ru/jour/article/view/2267
• ISSN: 2500-0462; 2500-3259

Russia does not possess  as many highly adaptable, technological, early-ripening varieties of sweet  cherry (Prunus avium L.) as would suffice to feel comfortable. Therefore, breeders are faced with the task of obtaining hybrid seeds as soon  as possible. This task is not easy because of low field germination rates of hybrid seeds. The goal of our research  was to select the best environments and ways to reduce  infection while obtaining the largest number of full-fledged sweet cherry seedlings  from intraspecific hybridization  in vitro and to accelerate the selection process. Work on the  in vitro cultivation  of germs  of intraspecific  hybrids  from four combinations of crosses  of the  promising varieties and sweet cherry donors ‘Valerij Chkalov’ × ‘Svithart’, ‘Krasnodarskaya Rannaya’ × ‘Krupnoplodnaya’, ‘Jaroslavna’ × ‘Svееthart’, ‘Еiforiya’ × ‘Svееthart’ under  the “early-ripening and  large-fruited” program started with prebreeding and the selection of maternal and paternal forms of sweet cherries. In the course of research, the terms of taking fruits for planting in vitro culture have been determined, which correspond to the end of May and the beginning of June. The process of sterilization from saprophytic microflora of fruits, stone and seeds before cultivation has been optimized. Three modified media with macro- and microelements based on Murashige and Skoog, Prunus and Smirnova were tested and assessed for suitability for cultivation of cherry embryos. According to the results of the experiments, an agarized  M4 artificial nutrient medium  based  on the Murashige and Skoog formulations with the addition  of ascorbic acid and sucrose was proposed as the most optimal for germination and providing  excellent nutrition.  Mass germination from bud seedlings  of these  hybrid combinations of sweet  cherry crosses, when applying  the developed scheme,  was noted in our experiments as early as in the first decade of July, i. e. about a month and a half after putting them into culture. The efficiency of growing hybrid seedlings of early-ripening sweet cherries with the use of embryo  culture is indisputable, since it makes it possible to produce hybrids in the same year when the crosses are made.