Grassland Root Communities: Species Distributions and How They Are Linked to Aboveground Abundance.

There is little comprehensive information on the distribution of root systems among coexisting species, despite the expected importance of those distributions in determining the composition and diversity of plant communities. This gap in knowledge is particularly acute for grasslands, which possess large numbers of species with morphologically indistinguishable roots. In this study we adapted a molecular method, fluorescent fragment length polymorphism, to identify root fragments and determine species root distributions in two grasslands in Yellowstone National Park. Aboveground biomass was measured and soil cores (2 cm diam) were collected to 40 cm and 90 cm in an upland, dry grassland and a mesic, slope-bottom grassland, respectively, at peak foliar expansion. Cores were subdivided and species that occurred in each 10 cm interval were identified. The results indicated that the average number of species in 10 cm intervals (31 cm3) throughout the sampled soil profile was 3.9 and 2.8 at a dry and a mesic grassland, respectively. By contrast, average species number per 0.5 m2 determined by the presence of shoot material was 6.7 and 14.1 at dry and mesic sites, respectively. There was no relationship between soil depth and number of species per 10 cm interval in either grassland, despite the exponential decline of root biomass with soil depth at both sites. There also was no relationship between root frequency (i.e., the percentage of samples in which a species occurred) and soil depth for the vast majority of species at both sites. The preponderance of species were distributed throughout the soil profile at both sites. Assembly analyses indicated that species root occurrences were randomly assorted in all soil intervals at both sites, with the exception that F. idahoensis segregated from A. tridentata and P. spicata in 10-20 cm soil at the dry grassland. Root frequency throughout the entire sampled soil profile was positively associated with shoot biomass among species. Together these results indicated the importance of large, well proliferated root systems in establishing aboveground dominance. The findings suggest that spatial belowground segregation of species probably plays a minor role in fostering resource partitioning and species coexistence in these YNP grasslands

Quantifying the UV-continuum slopes of galaxies to z ˜ 10 using deep Hubble+Spitzer/IRAC observations

Measurements of the UV-continuum slopes β provide valuable information on the physical properties of galaxies forming in the early universe, probing the dust reddening, age, metal content, and even the escape fraction. While constraints on these slopes generally become more challenging at higher redshifts as the UV-continuum shifts out of the Hubble Space Telescope bands (particularly at z > 7), such a characterization actually becomes abruptly easier for galaxies in the redshift window z = 9.5-10.5 due to the Spitzer/Infrared Array Camera 3.6 μm-band probing the rest-UV continuum and the long wavelength baseline between this Spitzer band and the Hubble Hf160w band. Higher S/N constraints on β are possible at z ˜ 10 than at z = 8. Here, we take advantage of this opportunity and five recently discovered bright z = 9.5-10.5 galaxies to present the first measurements of the mean β for a multi-object sample of galaxy candidates at z ˜ 10. We find the measured βobs's of these candidates are -2.1 ± 0.3 ± 0.2 (random and systematic), only slightly bluer than the measured β's (βobs ≈ -1.7) at 3.5 < z < 7.5 for galaxies of similar luminosities. Small increases in the stellar ages, metallicities, and dust content of the galaxy population from z ˜ 10 to z ˜ 7 could easily explain the apparent evolution in β

Independent mutations in a single locus, the transcriptional factor MYB10, control natural variation in fruit color among Fragaria species

External and internal fruit color are important traits in strawberry (Fragaria spp.) breeding programs, where different preferences are sought depending on whether the fruits are produced for fresh consumption or processing. Therefore, there is a great interest in the development of predictive markers that effectively speed the development of new cultivars with increased consumer acceptance and/or which address processed fruit industry´s preferences. In order to identify loci controlling fruit color variation, two mapping populations were generated: one crossing diploid F. vesca parentals and another interspecific population between two octoploid species: the cultivated and the Chilean strawberry, F. x ananassa and F. chiloensis. Both populations allowed the detection of a QTL spanning a region of the F. vesca linkage group 1 (LG I) that includes the MYB10 gene, a known key regulator of anthocyanin biosynthesis. Mapping by sequencing in the F. vesca population revealed an LTR retrotransposon inserted in the third exon of FvMYB10, which produces a premature stop codon, and co-segregates with white fruits in the entire population. Genotyping by Sanger sequencing of additional white-fruited F. vesca accessions resulted in the identification of another three independent mutations in MYB10, two of them not previously described1. In octoploid strawberry, a mayor QTL on LG I-3 controls about 55% variation in internal flesh color and is associated with an insertion in the promoter region of FcMYB10. Similar insertions have been detected in other F. chiloensis accessions bearing white fruits. In all cases, transient over-expression of FvMYB10 restored anthocyanin biosynthesis and red color in fruit flesh and skin, indicating that lack of function of MYB10 was the underlying cause of white fruits in all analyzed cases

The AIFS evaluation of the 2006 family law reforms : a summary

In 2006, the Australian Government, through the Attorney- General\u27s Department (AGD) and the Department of Families, Housing, Community Services and Indigenous Affairs (FaHCSIA), commissioned the Australian Institute of Family Studies (AIFS) to undertake an evaluation of the impact of the 2006 changes to the family law system: Evaluation of the 2006 Family Law Reforms (Kaspiew et al., 2009) (the Evaluation). This article provides a summary of the key findings of the Evaluation.<br /

Family violence : key findings from the evaluation of the 2006 family law reforms

The different types, prevalence and consequences of family violence, as demonstrated by the Australian Institute of Family Studies\u27 Evaluation of the 2006 Family Law Reforms, are discussed. Family violence is shown to be an extremely complex phenomenon, which affects the mental and social well-being of the children. Hence, different measures that can be adopted to deal with pre- and post-separation periods and child care problems are also analyzed.<br /

Allelic Variation of MYB10 Is the Major Force Controlling Natural Variation in Skin and Flesh Color in Strawberry (Fragaria spp.) Fruit

Independent mutations in the transcription factor MYB10 cause most of the anthocyanin variation observed in diploid woodland strawberry (Fragaria vesca) and octoploid cultivated strawberry (Fragaria x ananassa). The fruits of diploid and octoploid strawberry (Fragaria spp) show substantial natural variation in color due to distinct anthocyanin accumulation and distribution patterns. Anthocyanin biosynthesis is controlled by a clade of R2R3 MYB transcription factors, among which MYB10 is the main activator in strawberry fruit. Here, we show that mutations in MYB10 cause most of the variation in anthocyanin accumulation and distribution observed in diploid woodland strawberry (F. vesca) and octoploid cultivated strawberry (F. xananassa). Using a mapping-by-sequencing approach, we identified a gypsy-transposon in MYB10 that truncates the protein and knocks out anthocyanin biosynthesis in a white-fruited F. vesca ecotype. Two additional loss-of-function mutations in MYB10 were identified among geographically diverse white-fruited F. vesca ecotypes. Genetic and transcriptomic analyses of octoploid Fragaria spp revealed that FaMYB10-2, one of three MYB10 homoeologs identified, regulates anthocyanin biosynthesis in developing fruit. Furthermore, independent mutations in MYB10-2 are the underlying cause of natural variation in fruit skin and flesh color in octoploid strawberry. We identified a CACTA-like transposon (FaEnSpm-2) insertion in the MYB10-2 promoter of red-fleshed accessions that was associated with enhanced expression. Our findings suggest that cis-regulatory elements in FaEnSpm-2 are responsible for enhanced MYB10-2 expression and anthocyanin biosynthesis in strawberry fruit flesh.Peer reviewe

Allelic Variation of MYB10 is the Major Force Controlling Natural Variation of Skin and Flesh Color in Strawberry (Fragaria spp.) fruit

Anthocyanins are the principal color-producing compounds synthesized in developing fruits of strawberry (Fragaria spp.). Substantial natural variation in color have been observed in fruits of diploid and octoploid accessions, resulting from distinct accumulation and distribution of anthocyanins in fruits. Anthocyanin biosynthesis is controlled by a clade of R2R3 MYB transcription factors, among which MYB10 has been shown as the main activator in strawberry fruit. Here, we show that MYB10 mutations cause most of the anthocyanin variation observed in diploid woodland strawberry (F. vesca) and octoploid cultivated strawberry (F. ×ananassa). Using a mapping-by-sequencing approach, we identified a gypsytransposon insertion in MYB10 that truncates the protein and knocks out anthocyanin biosynthesis in a white-fruited F. vesca ecotype. Two additional lossof-function MYB10 mutations were identified among geographically diverse whitefruited F. vesca ecotypes. Genetic and transcriptomic analyses in octoploid Fragaria spp. revealed that FaMYB10-2, one of three MYB10 homoeologs identified, residing in the F. iinumae-derived subgenome, regulates the biosynthesis of anthocyanins in developing fruit. Furthermore, independent mutations in MYB10-2 are the underlying cause of natural variation in fruit skin and flesh color in octoploid strawberry. We identified a CACTA-like transposon (FaEnSpm-2) insertion in the MYB10-2 promoter of red-fleshed accessions that was associated with enhanced expression and anthocyanin accumulation. Our findings suggest that putative cis regulatory elements provided by FaEnSpm-2 are required for high and ectopic MYB10-2 expression and induction of anthocyanin biosynthesis in fruit flesh. We developed MYB10-2 (sub-genome) specific DNA markers for marker-assisted selection that accurately predicted anthocyanin phenotypes in octoploid segregating populations