Development of regenerated plants of interspecific wheat hybrids using immature embryos as explants

Abstract

Nowadays particular attention in winter wheat breeding is paid to the introduction of biotechnological methods. The culture of immature embryos in vitro is an alternative way to produce hybrids that often do not develop fully in vivo. The purpose of the current study was to estimate the ability of immature embryos of interspecific winter wheat hybrids for callus induction, morphogenesis, and plant regeneration on artificial nutrient media, as well as to select optimal conditions for obtaining full-fledged plants with all the botanical characteristics of the species. The research material included 5 hybrid combinations of interspecific crosses between durum (Triticum durum DESF.) and common (Triticum aestivum L.) winter wheat. The material was collected during one field season (2022). Immature embryos were used as explants. Culture media were according to Murashige-Skoog (MS), and they differed in the content of hormones and organic substances. There has been found that the hybrid combinations were characterized by a variety of morphogenic responses. The manifestation of callusogenesis was not high enough and averaged 22–32 % depending on the nutrient medium. Rhizogenesis averaged from 1–6.7 %, and ended with the formation of roots. The process of formation of embryoid- and hemmorizogenesis was best demonstrated by the hybrid combination No.1, and on two media. All processes of morphogenesis excepting ‘rhizogenesis’ varied greatly among hybrid combinations. The largest number of regenerated plants was obtained from hybrid combination No.1 (61 pcs., 54.5 %). After vernalization and acclimatization, 38 % of the plants survived from the number of planted embryos. The largest number of heads (79 pcs.) was formed according to hybrid combination No.1, on average 1.46 heads per plant. However, not all heads were fertile. The results of the correlation analysis made it possible to identify indicators that closely correlated with the amount of plant regeneration, namely, the high yield of embryoid- and hemmorizogenic structures ensured a high frequency of plant regeneration (r = 0.769).

Keywords

• winter wheat
• interspecific hybrids
• immature embryo
• regenerant plant
• hemmorizogenesis
• embryoidogenesis