Marker-assisted introgression (MAI) of almond genes into the peach background: a fast method to mine and integrate novel variation from exotic sources in long intergeneration species

This paper proposes a new breeding strategy, marker-assisted introgression (MAI), to obtain lines of perennial species with a single introgressed fragment from a compatible species two generations after the interspecific hybrid. MAI allows enrichment of the genome of a species with genes from a wild or exotic relative in a short timeframe and with an intermediate step that allows a first exploration of genes/QTLs that the donor species can provide to the target crop. This method has three phases: (1) creating a large backcross one (BC1) population to select, with markers, a reduced number of individuals (15–30, called the prIL set) with a low number of introgressions; (2) phenotyping the prIL set for the traits of interest and inferring the inheritance and map position of segregating major genes/QTLs based on the known genotypes of the prILs; and (3) advancing selected lines carrying the traits of interest to a next generation of backcross or selfing to obtain individuals with a single introgression in the background of the elite commercial germplasm. The proof of concept of this strategy was implemented by using peach as the recurrent species and almond as the donor. The whole process can be done in 9–10 years as the identification of the first line with one introgression was after 5 years (2006–2011), and 4–5 additional years are needed for phenotypic evaluation of selected lines. The expansion of this method to other perennial clonally propagated crops and to other species of Prunus compatible with peach is discussed.     

The Use of Kosher Phenotyping for Mapping QTL Affecting Susceptibility to Bovine Respiratory Disease

Bovine respiratory disease (BRD) is the leading cause of morbidity and mortality in feedlot cattle, caused by multiple pathogens that become more virulent in response to stress. As clinical signs often go undetected and various preventive strategies failed, identification of genes affecting BRD is essential for selection for resistance. Selective DNA pooling (SDP) was applied in a genome wide association study (GWAS) to map BRD QTLs in Israeli Holstein male calves. Kosher scoring of lung adhesions was used to allocate 122 and 62 animals to High (Glatt Kosher) and Low (Non-Kosher) resistant groups, respectively. Genotyping was performed using the Illumina BovineHD BeadChip according to the Infinium protocol. Moving average of -logP was used to map QTLs and Log drop was used to define their boundaries (QTLRs). The combined procedure was efficient for high resolution mapping. Nineteen QTLRs distributed over 13 autosomes were found, some overlapping previous studies. The QTLRs contain polymorphic functional and expression candidate genes to affect kosher status, with putative immunological and wound healing activities. Kosher phenotyping was shown to be a reliable means to map QTLs affecting BRD morbidity.     

The Allometry of Bee Proboscis Length and Its Uses in Ecology

Allometric relationships among morphological traits underlie important patterns in ecology. These relationships are often phylogenetically shared; thus quantifying allometric relationships may allow for estimating difficult-to-measure traits across species. One such trait, proboscis length in bees, is assumed to be important in structuring bee communities and plant-pollinator networks. However, it is difficult to measure and thus rarely included in ecological analyses. We measured intertegular distance (as a measure of body size) and proboscis length (glossa and prementum, both individually and combined) of 786 individual bees of 100 species across 5 of the 7 extant bee families (Hymenoptera: Apoidea: Anthophila). Using linear models and model selection, we determined which parameters provided the best estimate of proboscis length. We then used coefficients to estimate the relationship between intertegular distance and proboscis length, while also considering family. Using allometric equations with an estimation for a scaling coefficient between intertegular distance and proboscis length and coefficients for each family, we explain 91% of the variance in species-level means for bee proboscis length among bee species. However, within species, individual-level intertegular distance was a poor predictor of individual proboscis length. To make our findings easy to use, we created an R package that allows estimation of proboscis length for individual bee species by inputting only family and intertegular distance. The R package also calculates foraging distance and body mass based on previously published equations. Thus by considering both taxonomy and intertegular distance we enable accurate estimation of an ecologically and evolutionarily important trait.     

Constructions of race: symbolic ethnic capital and the performance of youth identity in multicultural Australia

The relationship between ethnicity and cultural and social capital has been taken up by several scholars in terms of questions of disadvantage. This paper considers the performance of race and ethnicity as positive capital among a group of Sudanese young people with refugee backgrounds in Brisbane, Australia. Based on ethnographic fieldwork, I demonstrate young people's adaptation of cultural associations in their hybridized and essentialized self-representations. In particular, I explore my informants’ use of hip hop music and style as resources in performance. Much of young people's engagement with capital in performance enables their relatively overt and self-conscious process of clarifying who they are in relationship to one another, often with particular reference to race and ethnicity. Their engagement with globally relevant mediums is indicative of young people's agency in defining their own lives in the context of the political and moral framework of Australian multiculturalism.     

Linking species functional roles to their network roles

Species roles in ecological networks combine to generate their architecture, which contributes to their stability. Species trait diversity also affects ecosystem functioning and resilience, yet it remains unknown whether species’ contributions to functional diversity relate to their network roles. Here, we use 21 empirical pollen transport networks to characterise this relationship. We found that, apart from a few abundant species, pollinators with original traits either had few interaction partners or interacted most frequently with a subset of these partners. This suggests that narrowing of interactions to a subset of the plant community accompanies pollinator niche specialisation, congruent with our hypothesised trade‐off between having unique traits vs. being able to interact with many mutualist partners. Conversely, these effects were not detected in plants, potentially because key aspects of their flowering traits are conserved at a family level. Relating functional and network roles can provide further insight into mechanisms underlying ecosystem functioning.