Bud-site selection in yeast offers an attractive system for studying cell polarity and asymmetric division. Haploids divide in an axial pattern, whereas diploids divide in a bipolar pattern. AXL1 is expressed in haploids but not diploids, and ectopic expression of AXL1 in diploids converts their bipolar budding pattern to an axial pattern. How Axl1 acts as a switch between the bipolar and axial...

Doubled haploid (DH) technology based on in vivo induction has gradually become the key modern maize breeding. The ability of maternal germplasm to be induced into haploids, inducibility, varies among genotypes. To dissect genetic basis inducibility (MHI), an F2 population derived from inbred lines B73 and Zheng58 was used for single environment QTL analysis by interaction analysis. mapping gen...

Chinese cabbage buds were soaked with Ethyl methanesulfonate (EMS) to induce mutagenesis. The influence of different EMS concentrations and treatment durations on microspore development, embryo production rate and seedling rate were evaluated in five Chinese cabbage genotypes. Mutations in four color-related genes were identified using high resolution melting (HRM) curves of their PCR products....

Doubled haploid (DH) populations are useful to scientists and breeders in both crop improvement and basic research. Current methods of producing DHs usually need in vitro culture for extracting haploids and chemical treatment for chromosome doubling. This report describes a simple method for synthesizing DHs (SynDH) especially for allopolyploid species by utilizing meiotic restitution genes. Th...

Production of maternal haploids via a male inducer can greatly accelerate maize breeding and is an interesting biological phenomenon in double fertilization. However, the mechanism behind haploid induction remains elusive. Segregation distortion, which is increasingly recognized as a potentially powerful evolutionary force, has recently been observed during maternal haploid induction in maize. ...

Mutator strains of yeast were used to accumulate random point mutations. Most of the observed changes in fitness were negative and relatively small, although major decreases and increases were also present. The average fitness of haploid strains was lowered by approximately 25% due to the accumulated genetic load. The impact of the load remained basically unchanged when a homozygous diploid was...

In budding yeast, spindle polarity relies on a precise temporal program of cytoplasmic microtubule-cortex interactions throughout spindle assembly. Loss of Clb5-dependent kinase activity under conditions of attenuated Cdc28 function disrupts this program, resulting in diploid-specific lethality. Here we show that polarity loss is tolerated by haploids due to a more prominent contribution of mic...

The objectives of this study were to assess the genetic variability of haploids (2n = 2x = 24) extracted from tetraploid Solanum tuberosum through 4x x 2x crosses with Solanum phureja. Molecular and phenotypic analyses were performed to fingerprint the genotypes used and to evaluate their potential use in breeding programs. AFLP analysis revealed the presence of specific bands derived from the ...

Chrysanthemum is one of important ornamental species in the world. Its highly heterozygous state complicates molecular analysis, so it is of interest to derive haploid forms. A total of 2579 non-fertilized chrysanthemum ovules pollinated by Argyranthemum frutescens were cultured in vitro to isolate haploid progeny. One single regenerant emerged from each of three of the 105 calli produced. Chro...

Interspecific hybridization has a much greater effect than chromosome doubling on gene expression; however, the associations between homeologous gene expression changes and polyhaploidization had rarely been addressed. In this study, cDNA-single strand conformation polymorphism analysis was applied to measure the expression of 30 homeologous transcripts in naturally occurring haploid (ABD, 2n =...