Targeted Knockout of Eukaryotic Translation Initiation Factor 4E Confers Bymovirus Resistance in Winter Barley.

The Eukaryotic Translation Initiation Factor 4E (EIF4E) is a well-known susceptibility factor for potyvirus infections in many plant species. The barley yellow mosaic virus disease, caused by the bymoviruses (BaYMV) and (BaMMV), can lead to yield losses of up to 50% in winter barley. In autumn, the roots of young barley plants are infected by the soil-borne plasmodiophoraceous parasite L.

Site-Directed Mutagenesis in Barley Using RNA-Guided Cas Endonucleases During Microspore-Derived Generation of Doubled Haploids.

In plant research and breeding, haploid technology is employed upon crossing, induced mutagenesis or genetic engineering to generate populations of meiotic recombinants that are themselves genetically fixed. Thanks to the speed and efficiency in producing true-breeding lines, haploid technology has become a major driver of modern crop improvement. In the present study, we used embryogenic pollen cultures of winter barley ( Hordeum vulgare ) for Cas9 endonuclease-mediated targeted mutagenesis in haploid cells, which facilitates the generation of homozygous primary mutant plants.

Barley (Hordeum vulgare L.) transformation using embryogenic pollen cultures.

The temperate cereal barley is grown as a source of food, feed, and malt. The development of a broad range of genetic resources and associated technologies in this species has helped to establish barley as the prime model for the other Triticeae cereals. The specific advantage of the transformation method presented here is that transgene homozygosity is attained in the same generation as the transgenic event occurred through the coupling of haploid technology with Agrobacterium-mediated transformation.

Validation of doubled haploid plants by enzymatic mismatch cleavage.

Background: Doubled haploidy is a fundamental tool in plant breeding as it provides the fastest way to generate populations of meiotic recombinants in a genetically fixed state. A wide range of methods has been developed to produce doubled haploid (DH) plants and recent advances promise efficient DH production in otherwise recalcitrant species. Since the cellular origin of the plants produced is not always certain, rapid screening techniques are needed to validate that the produced individuals are indeed homozygous and genetically distinct from each other.

The elimination of a selectable marker gene in the doubled haploid progeny of co-transformed barley plants.

Following the production of transgenic plants, the selectable marker gene(s) used in the process are redundant, and their retention may be undesirable. They can be removed by exploiting segregation among the progeny of co-transformants carrying both the selectable marker gene and the effector transgene. Here we show that the doubled haploid technology widely used in conventional barley breeding programmes represents a useful means of fixing a transgene, while simultaneously removing the unwanted selectable marker gene.