Application of in vitro pollination of opened ovaries to obtain Brassica oleracea L. × B. rapa L. hybrids

Abstract

This study presents the results of experiments concerning: (1) interspecific hybridization of Brassica oleracea × Brassica rapa via application of in vitro placental pollination and (2) embryological analysis of the process of resynthesis of Brassica napus. In order to overcome certain stigma/style barriers, B. rapa pollen was placed in vitro on an opened B. oleracea ovary (with style removed). Pollinated ovaries were cultured on Murashige and Skoog (MS) medium. After 24-d culture, the developing embryos were isolated from immature seeds and transferred onto MS medium supplemented with 0.47 μM kinetin, 0.49 μM 1-naphthaleneacetic acid, and 10% (v/v) coconut water. When the embryos had turned green, they were immediately placed onto MS medium with 100 μM kinetin. After development of the seedling, plantlets were transferred to soil. Chromosome doubling was achieved after another week. Cytometric analysis of nuclear DNA confirmed the hybrid nature of the plants. Resynthesis of B. napus can be performed through interspecific hybridization of B. oleracea × B. rapa followed by embryo rescue and genome doubling.

Interspecific Hybridization for Brassica Crop Improvement

“…However, a number of strategies exist to overcome these pre-and post-fertilization barriers (reviewed by [129]). Early pollination of stigmas (before buds open and before full maturity) or stump pollination can help in overcoming reproductive incompatibilities between some genotypes of Brassica species [130], while in other cases in vitro pollination of the stigma or pistils and/or opened ovules and ovaries may facilitate the interspecific fertilization event [131]. Seed abortion post-fertilization is also often observed in crosses between plants of different species or ploidy levels [132].…”

Development of new restorer lines for CMS <i>ogura</i> system with the use of resynthesized oilseed rape (<i>Brassica napus</i> L.)

“…acephala var. sabellica (curly kale) using the embryo rescue technique, thereby doubling the chromosome number of regenerated plants ( Sosnowska et al 2010 , Sosnowska and Cegielska-Taras 2014 ). RS2 plant was used as pollinators to cross with two double-low restorer lines of winter oilseed rape: 1202/3 and 1215/4.…”

Genetically Modified Natural Plants: Horizontal Gene Transformation

“…Özellikle klasik ıslah uygulamalarında hali hazırda kullanılabilir bir genetik materyal yoksa ya da arzu edilen bitki materyali mevcut değilse genetik tabanı birbirinden çok uzak olan bitkiler melezlenmekte ve devamında açılım gösteren F2 jenerasyonlarında seleksiyon uygulamaları ile istenilen özelliğe sahip bitkiler belirlenmeye çalışılmaktadır [83][84][85]. Hatta bu uygulamalarda, melezlemede kullanılacak ebeveyn bitkiler bazen doğada uyuşmaz oldukları ve normalde verimli döller veremedikleri halde kontrollü şartlarda (in vitro tozlanma ve döllenme, embryo kurtarma, türler arası melezleme vb) melezlemeler yapılarak döl verebilir hale getirilebilmektedirler [86][87][88]. Ancak eğer melezlemeye girebilecek ebeveyn bitki materyali yoksa bu durumda fiziksel ya da kimyasal mutajenler kullanılarak hedef bitki genomunda tesadüfi kalıcı mutasyonlar oluşturulmakta ve bu mutantlar arasından arzu edilen özellikleri taşıyanlar mutant bitkiler tespit edilmeye çalışılmaktadır [89][90][91].…”