In vitro androgenesis and somatic embryogenesis in wheat (Triticum aestivum L.)

Wheat (Triticum aestivum L.) is one of the most important staple food crops in the world, with over varieties are grown under diverse geographical conditions. Today, it is crucial to develop wheat varieties that have tolerance to various biotic factors and abiotic stress conditions, particlarly those arising from climate change. In vitro androgenesis and somatic embryogenesis techniques are among the most significant biotechnological methods that accelerate wheat breeding and cultivation. The research basically consists of two main areas; androgenesis and somatic embryogenesis studies. These studies aimed to develop improved protocols for the production of high numbers of haploid/doubled haploid plants by androgenesis (using microspore and anther culture) and to establish high-efficiency somatic embryogenesis protocols using scutellum and leaf explants in various spring and winter wheat varieties, including bread wheat (T. aestivum. L) and durum wheat (T. turgidum. desf). In order to establish these protocols, we investigated the effects of several key factors (genotype, explant, induction and regeneration media) on microspore embryogenesis and somatic embryogenesis processes focusing on embryoid/embryo and shoot/plant formation . Androgenesis experiments were conducted in three groups, using Altındane, Dariel, Pehlivan, Ceyhan-99, Sagittario, Bayraktar and Esperia bread wheat varieties, as well as Svevo, Sarıçanak, Eminbey and Kiziltan durum wheat varieties as plant materials. In group I, II and III experiments , 5, 18 and 8 different induction media, respectively, were tested in anther and microspore cultures containing microspores of some of the above genotypes in the middle to late single-nucleate stage. Additionlly somatic embryogenesis studies conducted in four groups using the Ceyhan-99, Sagittario, Svevo and Sarıçanak genotypes in I, II, III and IV. group experiments. Each genotype's scutellum and leaf explants were cultured in 9 different induction media. These induction media were prepared by adding different types and concentrations of plant growth regulators, glutamine, and arabinogalactan to different basic nutrient media, with maltose or sucrose as carbohydrate source. The structures formed in the induction media were cultured in different regeneration media to be transformed into plants. The results of the androgenesis trial in this thesis highlighted the significance of genotype and induction medium factors in androgenic responses, including the induction and regeneration of embryoids, as well as the production of albino and green plant in wheat. Overall, the study found that more embryoids were obtained from microspore culture campared to anther culture. In the somatic embryogenesis trial results, bread wheat genotypes showed superior performance than durum wheat genotypes across all examined parameters of somatic embryogenesis. Regarding of explant source, scutellum explants showed higher response than leaf explants in total callus production, embryogenic callus production, callus size, green spot formation, shoot per callus and regenerated plant per callus. However leaf explants produced heavier calli, which may be potentially useful for in vitro secondary metabolite production.