AGRICULTURAL BIOLOGY, 2016, V. 51, ¹ 5, pp. 636-644 ISSN 2412-0324 (English ed. Online) (SEL’SKOKHOZYAISTVENNAYA BIOLOGIYA) ISSN 0131-6397 (Russian ed. Print) ISSN 2313-4836 (Russian ed. Online) Plant breeding: tissue cultures, molecular markers UDC 633.63:631.52:581.3 doi: 10.15389/agrobiology.2016.5.636rus doi: 10.15389/agrobiology.2016.5.636eng SUGAR BEET (Beta vulgaris L.) HAPLOID PARTHENOGENESIS in vitro: FACTORS AND DIAGNOSTIC CHARACTERS T.P. ZHUZHZHALOVA, O.A. PODVIGINA, V.V. ZNAMENSKAYA, E.N. VASIL’CHENKO, N.A. KARPECHENKO, O.A. ZEMLYANUKHINA A.L. Mazlumov All-Russian Research Institute of Sugar Beet and Sugar, Federal Agency of Scientific Organizations, 86, VNIISS, Ramon Region, Voronezh Province, 396030 Russia, e-mail biotechnogiya@mail.ru Acknowledgements: Supported by the grant of the President of the Russian Federation for the Leading Scientific Schools of Russia (HIII=5282.2014.4 — project «Development of plant reproduction theory as based on integrity and reliability of biosystems. <...> Polyvalent morphogenesis programs and their effective natural and artificial models») Received June 30, 2015 A b s t r a c t Traditional obtaining of inbred lines and hybrids in sugar beet breeding requires a long time and is labour-consuming because of 2-year cycle of plant development, self- and cross-incompatibility, and inbreeding depression. <...> To induce genotypic diversity in initial population, biotechnology methods including haploid parthenogenesis are promising. <...> We have shown that, when inducing sugar beet (Beta vulgaris L.) haploids in vitro, express-diagnostics using phenotypic and embryological characters that are representative of periods of flowering shoots, organs and buds development, and stages of embryo sac, ovule and pollen grains formation is effective. <...> The regenerative activity is observed in ovules of bud 1 to bud 25 located on ear part of pleochasium upward from the open flower. <...> The nuclei and cells of female gametophyte of isolated ovules under in vitro conditions are capable of neoplasm at all stages of development, but the 8-nuclear or 7-celled embryo sacs are the most appropriate to morphogenesis and switching of development program from gametophyte to sporophyte type. <...> Critical period of embryo sac development has been beforehand determined from the accompanying embryological characters — the presence of single-nuclear and two-three-celled pollen grains <...>