Male sterility and gametoclonal variations from gynogenically derived polyploids of tef (Eragrostis tef), zucc. Trotter

Abstract

The production of plants from the gynogenic culture of tef (Eragrostis tef) was reported from in vitro gynogenesis of unpollinated flower explant of cultivar 'DZ-01-196'. Out of the 159 regenerated R0 lines, 151 tetraploids, 5 di-haploids, 2 aneuploids and 1 octoploid plant were obtained which showed gametoclonal variation in various traits including male sterility. Panicle bending, accessory floret development and larger seed size were among the unique traits obtained. Analysis of variance revealed significant differences for all morphological traits studied in the R0 generations. Tetraploid R0s showed superiority over the control for plant height, flag leaf length and number of florets per spikelet. Male sterility traits were recorded among the tetraploid R0 lines mainly due to failure of pollen formation. Though two complete and four partial male sterile lines were obtained in the R0 generation, this trait was not exhibited in those plants raised from the partially male sterile lines. Male sterility and the various gametoclonal variations obtained from this study will facilitate the hybridization and crop improvement program of tef.

Haploids: Constraints and opportunities in plant breeding

“…Variation from gynogenically derived tef (Eragrostis teff (Zuccagni)), an important cereal crop of Ethiopia, was found for plant height, panicle length, culm thickness, seed size, and maturity (Gugsa and Loerz, 2013;Gugsa et al, 2006). Likewise, several DH regenerants obtained after anther culture (or microspores) showed large variation for improved agronomic characteristics in rice (Ying et al, 1996;Yoshida et al, 1998), while dihaploid plants in potato originating through gametoclonal variation during androgenic dihaploidization were genetically most distinct from their tetraploid anther-derived sibs as well as anther donor (Sarkar et al, 2010).…”

The efficacy of four gametocides for induction of pollen sterility in Eragrostis tef (Zucc.) Trotter

“…Attempts to improve grain yield have resulted in a number of improved varieties. However, breeding efforts to develop lodging-resistant tef varieties have not yet succeeded due to the tedious and meticulous crossing technique of tef, attributed to its pollination process (Gugsa and Loerz, 2013). In tef, pollination occurs only during the early hours of the morning and requires the employment of an appropriate artificial hybridization technique.…”

“…Under Ethiopian climatic conditions, tef flowers open and are fertilised only between 6:45 and 7:45 a.m. (Berhe, 1976;Ketema, 1997). In addition to this, the small size of its reproductive structures and its autogamous nature has made microscopic emasculation and cross pollination obligatory, which requires appropriate equipment and skilled personnel (Berhe and Miller, 1976;Ketema, 1997;Gugsa and Loerz, 2013). In a selfpollinated crop such as tef, with the male and female organs in the same flower (monoecious), the application of chemical hybridizing agents (CHAs) that selectively impair the male gamete would be of a great value in plant breeding or genetic analysis of traits, reducing the time invested in the laborious procedure of hand emasculation.…”