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Phenotypic stereotypes are traits, often polygenic, that have been stringently selected to conform to specific criteria. In dogs, Canis familiaris, stereotypes result from breed standards set for conformation, performance (behaviors), etc. As a consequence, phenotypic values measured on a few individuals are representative of the breed stereotype. We used DNA samples isolated from 148 dog breeds to associate SNP markers with breed stereotypes. Using size as a trait to test the method, we identified six significant quantitative trait loci (QTL) on five chromosomes that include candidate genes appropriate to regulation of size (e.g., IGF1, IGF2BP2 SMAD2, etc.). Analysis of other morphological stereotypes, also under extreme selection, identified many additional significant loci. Less well-documented data for behavioral stereotypes tentatively identified loci for herding, pointing, boldness, and trainability. Four significant loci were identified for longevity, a breed characteristic not under direct selection, but inversely correlated with breed size. The strengths and limitations of the approach are discussed as well as its potential to identify loci regulating the within-breed incidence of specific polygenic diseases.

Genetic variation in functionally integrated skeletal traits can be maintained over 10 million years despite bottlenecks and stringent selection. Here, we describe an analysis of the genetic architecture of the canid axial skeleton using populations of the Portuguese Water Dog Canis familiaris) and silver fox (Vulpes vulpes). Twenty-one skeletal metrics taken from radiographs of the forelimbs and hind limbs of the fox and dog were used to construct separate anatomical principal component (PC) matrices of the two species. In both species, 15 of the 21 PCs exhibited significant heritability, ranging from 25% to 70%. The second PC, in both species, represents a trade-off in which limb-bone width is inversely correlated with limb-bone length. PC2 accounts for approximately 15% of the observed skeletal variation, ~30% of the variation in shape. Many of the other significant PCs affect very small amounts of variation (e.g., 0.2-2%) along trade-off axes that partition function between the forelimbs and hind limbs. These PCs represent shape axes in which an increase in size of an element of the forelimb is associated with a decrease in size of an element of the hind limb and vice versa. In most cases, these trade-offs are heritable in both species and genetic loci have been identified in the Portuguese Water Dog for many of these. These PCs, present in both the dog and the fox, include ones that affect lengths of the forelimb versus the hind limb, length of the forefoot versus that of the hind foot, muscle moment (i.e., lever) arms of the forelimb versus hind limb, and cortical thickness of the bones of the forelimb versus hind limb. These inverse relationships suggest that genetic regulation of the axial skeleton results, in part, from the action of genes that influence suites of functionally integrated traits. Their presence in both dogs and foxes suggests that the genes controlling the regulation of these PCs of the forelimb versus hind limb may be found in other tetrapod taxa.

The first genetic transcript map of tim soybean genome was created by mapping one SNP in each of 1141 genes in one or more of three recombinant inbred line mapping populations, thus providing a picture of the distribution of genic sequences across the mapped portion of the genome. Singlenucleotide polymorphisms (SNPs) were discovered via the resequencing of sequence-tagged sites (STSs) developed from expressed sequence tag (EST) sequence. From an initial set of 9459 polymerase chain reaction primer sets designed to a diverse set of genes, 4240 STSs were amplified and sequenced in each of six diverse soybean genotypes. In the resulting 2.44 Mbp of aligned sequence, a total of 5551 SNPs were discovered, including 4712 single-base changes and 839 indels for an average nucleotide diversity of [theta] = 0.000997. The analysis of the observed genetic distances between adjacent genes vs. the theoretical distribution based upon the assumption of a random distribution of genes across the 20 soybean linkage groups clearly indicated that genes were clustered. Of the 1141 genes, 291 mapped to 72 of the 112 gaps of 5-10 cM in the preexisting simple sequence repeat (SSR)-based map, while 111 genes mapped in 19 of the 26 gaps >10 cM. The addition of 1141 sequence-based genic markers to the soybean genome map will provide an important resource to soybean geneticists for quantitative trait locus discovery and map-based cloning, as well as to soybean breeders who increasingly depend upon marker-assisted selection in cultivar improvement.

Cyclic voltammetry, NMR and ESR spectroscopy were used in the study of the electrochemical behavior of the ferracarborane clusters Cp*FeIIH(Et2C2B4H4) andCp*FeIII(Et2C2B4H4) and the phenylene-linked diiron species (Et2C2B4H4)FeIIH(C5Me4-C6H4-C5Me4)FeIII(Et2C2B4H4), ((Et2C2B4H4)FeH(C5Me4))2C6H4 and ((Et2C2B4H4)FeIII(C5Me4))2C6H4. Results showedthe importance of the R2C2B4H4(super 2-) ligands as organometallic synthetic agents and as mono- and dimetallic complex electronic stabilizers.

The emerald ash borer (EAB) Agrilus planipennis Fairmaire (Coleoptera: Buprestidae) is an invasive woodboring beetle native to northeastern Asia that continues to expand its range within North America and European Russia. The insect reproduces within and kills most North American species of ash Fraxinus spp.Because both the adult and larval life stages of EAB are difficult to detect prior to development of tree symptoms, much work has focused on quantifying spread and clarifying the potential movement pathways to improve early detection and monitoring strategies.In the present study, we retrospectively analyzed county‐level infestations of emerald ash borer in the state of Iowa, U.S.A., subsequent to the initial detection of EAB in 2010. Visual data analysis had suggested that new infestations were not in accordance with the expected patterns of establishment along roads, near campgrounds or by large population centres.We found a positive correlation between the establishment and detection of EAB in Iowa counties and the length of railroads in each county. To our knowledge, this is the first statistically significant association between rail pathways and the spread of EAB on the North American continent. [ABSTRACT FROM AUTHOR]

Soil waterlogging is a major environmental stress that suppresses soybean [Glycine max (L.) Merr.] growth and yield. Our objective was to identify quantitative trait loci (QTL) associated with the tolerance of soybean to soil waterlogging. We subjected 208 lines of two recombinant inbred (RI) populations, `Archer' x `Minsoy' and `Archer' x `Noir I', to 2 wk of waterlogging when the plants were at the early flowering stage. The control plants were not flooded. The experiment was conducted in three environments: Columbus, OH, in 1997 and 1998 and Wooster, OH, in 1998. We identified a single QTL, linked to marker Sat_064, from the Archer parent which was associated with improved plant growth (from 11-18%) and grain yields (from 47-180%) in waterlogged environments. This highly significant QTL (P = 0.02-0.000001) was identified in both RI populations and at both Columbus 1997 and 1998 environments, but not at the Wooster 1998 environment. The differences in soil type and flooding treatment (stagnant versus moving water) could have contributed to the lack of QTL identification at the Wooster 1998 environment. The Sat_064 QTL was uniquely associated with waterlogging tolerance and was not associated with maturity, normal plant height or grain yields. The Sat_064 marker maps close to the Rps4 gene for Phytophthora (Phytophthora sojae M.J. Kaufmann & J.W. Gerdemann) resistance; however, since Archer does not contain the Rps4 resistance allele, it is probably not a disease tolerance QTL. Near isogenic lines with and without the Sat_064 marker have been developed and are being field tested under waterlogging conditions to confirm the association of the QTL with the tolerance of soybean to waterlogging stress., PERIODIC FLOODING during the growing season adversely affects soybean growth and grain production in many areas of the USA and the rest of the world. (Stanley et al., 1980; Oosterhuis [...]

Based on the results given in a previous abstract, a more extensive study was performed to assess the genetic basis of seed abortion and reproduction in soybean. For this study, reproductive data were obtained from two replications of three different RI populations derived from the three parents Minosy, Noir 1 and Archer grown under typical agronomic conditions. This study surveyed a more extensive list of reproductive parameters (number of nodes per plant, nodal length, number of fruits per node, nodal position of fruits, number of fruits/plant, number of ovules per pod, number of filled seeds per pod, seed/ovule, and developmental stage and position of abortions). In addition, a variety of agronomic traits (seed number, seed weight, total yield, leaf shape, oil content of seeds, number of flowers per plant, protein content of seed, etc.) were measured in the same experiment. All reproductive and agronomic traits were compared with three existing genetic linkage maps. of genotypes from these RI populations. Quantitative trait loci (QTLs) responsible for the variation in reproductive traits were identified and also analyzed for interactions with other QTLs. These results were compared with data (given in previous abstract) obtained from different environmental conditions (Utah vs. Minnesota).

Genetic basis of embryo abortion in Glycine max was analzyed using a large Recombinant Inbred (RI) population. RI lines (including three replicates), parental lines (Minsoy & Noir 1) and 'Check' cultivars were planted in hill plots. Fifty fruits from each hill were analyzed for reproductive, quantitative traits (number of ovules per pod, number of filled seeds per pod, seed/ovule, and developmental stage and position of abortions). Parental lines differed significantly for traits. Average values for the RI population were intermediate between the parents. Some segregants had high frequencies of four ovules or seeds per pod, whereas parents and 'Checks' did not. There was a positive correlation between yield and ovules per pod and between seed number and ovules per pod. No correlation was observed between variation in pod size and seed/ovule. If abortion occurred within a pod there was a greater probability that another abortion would occur at the same developmental stage. Most abortions fell in the first position within the fruit. Abortions were observed at all developmental stages, but primarily occurred at two of four stages. Six significant QTLs were associated with reproductive traits. QTLs accounted for 36% of the variation in ovule or seed number. Two QTLs were involved in interactions with another locus.

The molecular sensor of innocuous (painless) cold sensation is well-established to be transient receptor potential cation channel, subfamily M, member 8 (TRPM8). However, the role of transient receptor potential cation channel, subfamily A, member 1 (TRPA1) in noxious (painful) cold sensation has been controversial. We find that TRPA1 channels contribute to the noxious cold sensitivity of mouse somatosensory neurons, independent of TRPM8 channels, and that TRPA1-expressing neurons are largely non-overlapping with TRPM8-expressing neurons in mouse dorsal-root ganglia (DRG). However, relatively few TRPA1-expressing neurons (e.g., responsive to allyl isothiocyanate or AITC, a selective TRPA1 agonist) respond overtly to cold temperature in vitro , unlike TRPM8-expressing neurons, which almost all respond to cold. Using somatosensory neurons from TRPM8−/− mice and subtype-selective blockers of TRPM8 and TRPA1 channels, we demonstrate that responses to cold temperatures from TRPA1-expressing neurons are mediated by TRPA1 channels. We also identify two factors that affect the cold-sensitivity of TRPA1-expressing neurons: (1) cold-sensitive AITC-sensitive neurons express relatively more TRPA1 transcripts than cold-insensitive AITC-sensitive neurons and (2) voltage-gated potassium (K V ) channels attenuate the cold-sensitivity of some TRPA1-expressing neurons. The combination of these two factors, combined with the relatively weak agonist-like activity of cold temperature on TRPA1 channels, partially explains why few TRPA1-expressing neurons respond to cold. Blocking K V channels also reveals another subclass of noxious cold-sensitive DRG neurons that do not express TRPM8 or TRPA1 channels. Altogether, the results of this study provide novel insights into the cold-sensitivity of different subclasses of somatosensory neurons. [ABSTRACT FROM AUTHOR]

1. Dispersal and host detection are behaviours promoting the spread of invading populations in a landscape matrix. In fragmented landscapes, the spatial arrangement of habitat structure affects the dispersal success of organisms. 2. The aim of the present study was to determine the long distance dispersal capabilities of two non-native pine bark beetles ( Hylurgus ligniperda and Hylastes ater) in a modified and fragmented landscape with non-native pine trees. The role of pine density in relation to the abundance of dispersing beetles was also investigated. 3. This study took place in the Southern Alps, New Zealand. A network of insect panel traps was installed in remote valleys at known distances from pine resources (plantations or windbreaks). Beetle abundance was compared with spatially weighted estimates of nearby pine plantations and pine windbreaks. 4. Both beetles were found ≥25 km from the nearest host patch, indicating strong dispersal and host detection capabilities. Small pine patches appear to serve as stepping stones, promoting spread through the landscape. Hylurgus ligniperda (F.) abundance had a strong inverse association with pine plantations and windbreaks, whereas H. ater abundance was not correlated with distance to pine plantations but positively correlated with distance to pine windbreaks, probably reflecting differences in biology and niche preferences. Host availability and dispersed beetle abundance are the proposed limiting factors impeding the spread of these beetles. 5. These mechanistic insights into the spread and persistence of H. ater and H. ligniperda in a fragmented landscape provide ecologists and land managers with a better understanding of factors leading to successful invasion events, particularly in relation to the importance of long-distance dispersal ability and the distribution and size of host patches. [ABSTRACT FROM AUTHOR]

Sirex nigricornis F. (Hymenoptera: Siricidae) is an innocuous pine-inhabiting woodwasp native to eastern North America, utilizing dead or dying pine trees as hosts. Although S. nigricornis F. does not cause economic damage, a closely related species, Sirex noctilio, was discovered in New York in 2004 and has continually spread throughout the northeastern United States and southern Canada, threatening the multi-billion-dollar pine timber industry of the southeastern United States and raising interest about potential interactions with native woodwasps and associated mortality agents. A non-sterilizing strain of the biological control agent, Deladenus siricidicola Bedding (Tylenchida: Neotylenchidae), was introduced along with S. noctilio but is not inhibiting the spread or establishment of S. noctilio. A North American congener, Deladenus proximus Bedding, has been recently isolated from S. noctilio and shows promise as a biological control agent. To better understand the potential of D. proximus as a control agent for S. noctilio, we measured and dissected nearly 1,200 S. nigricornis females from Arkansas and Mississippi and evaluated differences among collection location with regard to nematode virulence, woodwasp body size, and egg load. Body size and egg load were related to collection location, and nematode infestation resulted in significantly smaller females who produced significantly fewer eggs. Female woodwasps, especially those collected in Arkansas, were often fully sterilized by nematodes, and a higher percent sterilization was inversely related to body size and fewer eggs. We propose field studies to test the nematode's ability to sterilize S. noctilio in the northeastern United States. [ABSTRACT FROM AUTHOR]