Gametes have the unique potential to enter the sporophytic pathway, called androgenesis. The plants produced are usually haploid and recombinant due to the preceding meiosis and they can double their chromosome number to form doubled haploids, which are completely homozygous. Availability of the doubled haploids facilitates mapping the genes of agronomically important traits, shortening the tim...

Speciation is always a contentious and challenging issue following with the presence of gene flow. In Gossypium, there are many valuable resources and wild diploid cotton especially C and B genome species possess some excellent traits which cultivated cotton always lacks. In order to explore character transferring rule from wild cotton to upland tetraploid cotton, the [G. capitis-viridis × (G. ...

N 1963, we reported that Tradescantia microspores treated with histidine or I proline prior to irradiation in helium showed fewer chromosome aberrations than the controls. In 1960 and 1962, similar results were obtained when material was pretreated in ATP, agreeing in general with the results that WOLFF and LUIPPOLD (1956) found in their work with Vicia faba. In 1960, we demonstrated by postirr...

The 24-nucleotides (nt) phased secondary small interfering RNA (phasiRNA) is a unique class of plant small RNAs abundantly expressed in monocot anthers at early meiosis. Previously, 44 intergenic regions were identified as the loci for longer precursor RNAs of 24-nt phasiRNAs (24-PHASs) in the rice genome. However, the regulatory mechanism that determines spatiotemporal expression of these RNAs...

The anther-specific gene LLA1271 isolated from lily (Lilium longiflorum Thunb.) anthers is novel and exists in two forms. The protein encoded by LLA1271 may represent an adhesin-like protein first found in higher plants. The protein contains a typical N-terminal signal peptide followed by a highly conserved repeat domain. The LLA1271 gene is temporally expressed at the phase of microspore devel...

Aloe L. includes plants of economic interest worldwide for their medicinal properties and ornamental character. In this study, morphological cytogenetic traits were evaluated in a hybrid obtained using jucunda Reyn. as pollen donor A. vera (L.) Burm. f. female parent, to characterize it, determine its agronomic potentialities aspects related reproduction. Conventional protocols morphometric stu...

Chemical hybridization agent (CHA)-induced male sterility is an important tool in crop heterosis. To demonstrate that CHA-SQ-1-induced male sterility is associated with abnormal tapetal and microspore development, the cytology of CHA-SQ-1-treated plant anthers at various developmental stages was studied by light microscopy, scanning and transmission electron microscopy, in situ terminal deoxynu...

The plant hormone gibberellic acid (GA) controls many physiological processes, including cell differentiation, cell elongation, seed germination, and response to abiotic stress. In this study, we report that exogenous treatment of flowering Arabidopsis (Arabidopsis thaliana) plants with GA specifically affects the process of male meiotic cytokinesis leading to meiotic restitution and the produc...

Ploidy level is one of important factors for plant breeders; therefore models that can predict it are very practical. To estimate of ploidy levels in some species, hybrids and cultivars of Rosa, dimensions of over 500 pollens include pollen length, width and area measured at ABRII. The calculations were carried out in several stages. First, Ploidy levels were regressed with pollen dimensions, a...