Microspores can be induced to develop homozygous doubled haploid plants in a single generation. In the present experiments androgenic microspores of wheat have been genetically transformed and developed into mature homozygous transgenic plants. Two different transformation techniques were investigated, one employing electroporation and the other co-cultivation with Agrobacterium tumefaciens. Di...

Pollen grains display a wide range of variation in aperture number and arrangement (pattern) in angiosperms. Apertures are well-defined areas of the pollen wall surface that permit pollen tube germination. For low aperture numbers, aperture patterns are characteristic of the major taxonomic divisions of angiosperms. This paper presents a developmental model that explains most of the aperture pa...

Abstract The endogenous level of cytokinins (CKs) and auxins (Auxs) was analyzed in isolated microspores ovaries two doubled haploid (DH) lines triticale (× Triticosecale Wittm.) to better understand the mechanism microspore embryogenesis (ME)—the most efficient widely applied method producing DHs. responsiveness studied ME significantly varied. induced by pre-treating tillers with low temperat...

BACKGROUND AND AIMS Evolutionary transitions from heterostyly to dioecy have been proposed in several angiosperm families, particularly in Rubiaceae. These transitions involve the spread of male and female sterility mutations resulting in modifications to the gender of ancestral hermaphrodites. Despite sustained interest in the gender strategies of plants, the structural and developmental bases...

The accumulation of proline in anthers of Petunia was followed during flower bud development. Accumulation proceeded continuously from the microspore stage to anthesis except for an intervening period when bud length was between 15 and 35 mm. The second rise in proline content co­ incided with the stage of anther desiccation. The metabolism of proline 3 lA was studied in isolated branches fed w...

Aspterric Acid, 6-Hydroxymellein, Arabidopsis thaliana, Aspergillus terreus Aspterric acid (1) and 6-hydroxymellein (2), inhibitors of pollen development in Arabidopsis thaliana, have been isolated from the fungus Aspergillus terreus. 1 and 2 inhibited the pollen development at concentrations of 38 and 52 microM, respectively. The microscopic examination of pollen development suggested that the...

Here is reported a novel histological marker line that strongly and specifically labels the male gametophyte in Arabidopsis flowers, from the uninucleate microspore to the pollination stage. In this marker line, the expression of the UidA and GFP marker genes is driven by the promoter of the At5g17340 Arabidopsis gene, a gene highly expressed in the male gametophyte. Strong GUS histochemical st...

Cytogenetic studies were carried out on 22 accessions of Brachiaria jubata from the Embrapa Beef Cattle Brachiaria collection. One accession was diploid (2n = 2x = 18) and the remaining 21 were tetraploid (2n = 4x = 36). Among five tetraploid accessions, a specific and constant pattern of cell fusion involving only two microsporocytes was recorded. Meiosis proceeded normally from prophase I to ...