Studies on micropropagation of female spinach plants and the stability of sex expression in the regenerants.

从东方菠菜（Spinacia oleracea L.）在长日照条件下培养至开花。根据品种和供体植物，12.5%至80.5%的再生植株在不含生长调节剂的培养基上开花。来自雌性外植体的植株均为雌性，而来自雄性供体的植株包括雄核单胞菌。对再生愈伤组织再生植株进行性别表达研究。雌株再生群体中雌雄同株占63.7%，雄株再生群体中雌雄同株占11.8%~ 54.9%。赤霉酸（GA 3）的应用提高了雄激素的比例，但没有诱导绝对的性别转换，即，以菠菜根段为材料，研究了乙烯利、硝酸银和氨基乙氧乙烯甘氨酸（AVG）对菠菜胚性愈伤组织形成和胚状体发生的影响。乙烯利处理提高了胚性愈伤组织的形成率。AgNO 3和AVG抑制胚性愈伤组织的形成。在胚胎发生期，10 μ M乙烯利处理完全抑制胚胎的发育。相反，10 μ M AgNO_3的应用显著增加了胚胎的数量。

Somatic embryos obtained from the root callus of female or male plants of a oriental variety of spinach (Spinacia oleracea L.) were grown in vitro under long day length until flowering. Depending on the varieties and donor plants, 12.5 to 80.5% of regenerated plants flowered on a growth regulator-free medium. The plants derived from female explants were all female, while those from male donors included andromonoecy. The sex expression was pursued for plants regenerated from the regenerant-derived callus. The populations originating in female regenerants included gynomonoecy up to 63.7%, while 11.8 to 54.9% of those from male regenerants were andromonoecious. The application of gibberellic acid (GA3) elevated the ratio of andromonoecy but did not induce an absolute sex conversion, i.e., to the opposite sex.The effects of Ethephon, silver nitrate and aminoethoxyvinylglycine (AVG) on the embryogenic callus formation and embryogenesis were examined using tissue cultures of spinach root segments. The application of Ethephon increased the ratio of embryogenic callus formation. AgNO3 and AVG inhibited the embryogenic callus formation. Ethephon applied at 10muM during embryogenesis, however, completely inhibited the development of embryos. In contrast, the application of 10muM AgNO3 remarkably increased the number of embryos.