Inheritance of the traits of spike and grain color and morphometric parameters of the grain in F<Subscript>1</Subscript> and F<Subscript>2</Subscript> hybrids of <Emphasis Type=Italic>Triticum spelta</Emphasis> L. × <Emphasis Type=Italic>Triticum aestivum</Emphasis> L.

The character of inheritance of the morphological traits of spike and grain color and morphometric parameters of the grain in simple and backcross F₁ and F₂ hybrids of spelt and soft wheat has been investigated. The experiments confirmed that single homologous genes determine the trait of grain width in different species of wheat. Incomplete dominance of the gene that determines the trait of grain length has been revealed. The increase of the dosage of genes from one wheat species in a backcross hybrid has been shown to increase the deviation from the other species and to bring the values of the quantitative parameters of the grain closer to the values for the saturating species. Splitting of the spike color trait in the F₂ offspring has been shown to follow the 15: 1 dihybrid cross scheme and to be controlled by two dominant homologous genes.     

Direct embryogenesis and green plant regeneration from isolated microspores of hexaploid triticale (× <Emphasis Type="Italic">Triticosecale</Emphasis> Wittmack) cv. Bogo

The use of doubled haploids improves the efficiency of cultivar development in many crops and can be helpful in genetic and molecular studies. The major problem with this approach is the low efficiency of green plant regeneration. We describe here an efficient method for inducing embryos and regenerating green plants directly from isolated microspores of hexaploid triticale (× Triticosecale Wittmack) cv. Bogo. The absence of growth regulators in the induction medium was the most effective condition for the formation of embryo-like structures. The highest induction rates were observed at microspore densities of 1.5×10⁵ microspores and 2×10⁵ microspores per milliliter. Such cultures produced an average of 54.9 green plants per single donor spike. The frequency of albino plants ranged from 9.3% to 22.9%. Among the green progeny tested, 30.8% were spontaneously doubled haploids.Abbreviations BAP Benzylaminopurine - DAPI 4-6 Diamidino-2-phenylindole - 2,4-D 2,4-Dichlorophenoxyacetic acid - NAA -Naphthaleneacetic acid     

Transmission of chromosomes through the eggs and pollen of triticale × wheat F1 hybrids

Summary The substitution patterns of rye chromosomes in hexaploid triticale × wheat F₂ hybrids, along with the transmission patterns of rye chromosomes through egg cells and pollen when several of the F₁ hybrids were test crossed to triticale and wheat were investigated. The data indicated that the rye chromosome transmission through both the egg and pollen was random in number and in composition. The test crosses suggested that it was best to use wheat pollen for the transmission of rye chromosomes through the egg cells of the F₁ hybrids and triticale egg cells for the transmission of rye chromosomes through F₁ hybrid pollen. A deviation from random segregation in the F₂ and the transmission rate was observed for rye chromosomes 1R, 4R/7R, and 6R. The transmission rates of 1R and 6R varied depending on the direction in which the cross was made. The results also indicated that there was little or no compensation between the R- and D-genomes and that the chromosomes of these two genomes appeared to be transmitted independently of each other.     

A Tanganyikan cichlid <Emphasis Type=Italic>Neolamprologus mustax</Emphasis> selectively exploits territories of another cichlid <Emphasis Type=Italic>Variabilichromis moorii</Emphasis> due to its inter-individual variation in aggression

Wetland restoration in highly modified landscapes involves balancing target ecosystem functions and values with constraints of landscape and stakeholder context. Often, a restored wetland complex cannot meet all target conditions simultaneously, and tradeoffs must be understood, evaluated, and quantified. We examined the tradeoff between providing migratory bird sanctuary and increasing public recreational opportunities within a restored floodplain wetland complex along the Illinois River. We surveyed the distribution and behavior of waterbirds in response to a gradient of spatial and temporal disturbances from waterbird hunting activities. Using ArcMap and spatial interpolation of waterbird densities as a novel approach to quantify sanctuary area, we estimated that approximately 42% of Emiquon Preserve functioned as sanctuary across disturbance intensities, hunter distribution, and time periods during autumn migration. Waterbird abundance did not increase with short-term temporal sanctuary or decreased hunting intensity. Disturbance distance around hunting locations was 752.1 m, overall, and increased 38.4 m for each additional hunting party. Exclusion distance around hunting locations was greater in areas with greater mean disturbance frequency. We question the effectiveness of short-term temporal sanctuary for waterbirds at the expense of recreational opportunities and advocate our analytical approach to quantify sanctuary area and disturbance buffers without experimentally causing disturbances.     

The influence of Al<Superscript>3+</Superscript> on DNA methylation and sequence changes in the triticale (× <Emphasis Type="Italic">Triticosecale</Emphasis> Wittmack) genome

Abiotic stressors such as drought, salinity, and exposure to heavy metals can induce epigenetic changes in plants. In this study, liquid chromatography (RP-HPLC), methylation amplified fragment length polymorphisms (metAFLP), and methylation-sensitive amplification polymorphisms (MSAP) analysis was used to investigate the effects of aluminum (Al) stress on DNA methylation levels in the crop species triticale. RP-HPLC, but not metAFLP or MSAP, revealed significant differences in methylation between Al-tolerant (T) and non-tolerant (NT) triticale lines. The direction of methylation change was dependent on phenotype and organ. Al treatment increased the level of global DNA methylation in roots of T lines by approximately 0.6%, whereas demethylation of approximately 1.0% was observed in NT lines. DNA methylation in leaves was not affected by Al stress. The metAFLP and MSAP approaches identified DNA alterations induced by Al³⁺ treatment. The metAFLP technique revealed sequence changes in roots of all analyzed triticale lines and few mutations in leaves. MSAP showed that demethylation of CCGG sites reached approximately 3.97% and 3.75% for T and NT lines, respectively, and was more abundant than de novo methylation, which was observed only in two tolerant lines affected by Al stress. Three of the MSAP fragments showed similarity to genes involved in abiotic stress.