As population modeling is increasingly called upon to guide policy and management, it is important that we understand not only the central tendencies of our study systems, but the consequences of ...their variation in space and time as well. The invasive plant
Alliaria petiolata
(garlic mustard) is actively managed in the United States and is the focus of a developing biological control program. Two weevils (Coleoptera: Curculionidae:
Ceutorhynchus
) that reduce fecundity (
C. alliariae
) and rosette survival plus fecundity (
C. scrobicollis
) are under consideration for release pending host specificity testing. We used a demographic modeling approach to (1) quantify variability in
A. petiolata
growth and vital rates and (2) assess the potential for single- or multiple-agent biocontrol to suppress growth of 12
A. petiolata
populations in Illinois and Michigan studied over three plant generations. We used perturbation analyses and simulation models with stochastic environments to estimate stochastic growth rates (λ
S
) and predict the probability of successful management using either a single biocontrol agent or two agent species together. Not all populations exhibited invasive dynamics. Estimates of λ
S
ranged from 0.78 to 2.21 across sites, while annual, deterministic growth (λ) varied up to sevenfold within individual sites. Given our knowledge of the biocontrol agents, this analysis suggests that
C. scrobicollis
alone may control
A. petiolata
at up to 63% of our study sites where λ
S
> 1, with the combination of both agents predicted to succeed at 88% of sites. Across sites and years, the elasticity rankings were dependent on λ. Reductions of rosette survival, fecundity, or germination of new seeds are predicted to cause the greatest reduction of λ in growing populations. In declining populations, transitions affecting seed bank survival have the greatest effect on λ. This contrasts with past analyses that varied parameters individually in an otherwise constant matrix, which may yield unrealistic predictions by decoupling natural parameter covariances. Overall, comparisons of stochastic and deterministic growth rates illustrate how analyses of individual populations or years could misguide management or fail to characterize complex traits such as invasiveness that emerge as attributes of populations rather than species.
As population modeling is increasingly called upon to guide policy and management, it is important that we understand not only the central tendencies of our study systems, but the consequences of ...their variation in space and time as well. The invasive plant
Alliaria petiolata
(garlic mustard) is actively managed in the United States and is the focus of a developing biological control program. Two weevils (Coleoptera: Curculionidae:
Ceutorhynchus
) that reduce fecundity (
C. alliariae
) and rosette survival plus fecundity (
C. scrobicollis
) are under consideration for release pending host specificity testing. We used a demographic modeling approach to (1) quantify variability in
A. petiolata
growth and vital rates and (2) assess the potential for single- or multiple-agent biocontrol to suppress growth of 12
A. petiolata
populations in Illinois and Michigan studied over three plant generations. We used perturbation analyses and simulation models with stochastic environments to estimate stochastic growth rates (λ
S
) and predict the probability of successful management using either a single biocontrol agent or two agent species together. Not all populations exhibited invasive dynamics. Estimates of λ
S
ranged from 0.78 to 2.21 across sites, while annual, deterministic growth (λ) varied up to sevenfold within individual sites. Given our knowledge of the biocontrol agents, this analysis suggests that
C. scrobicollis
alone may control
A. petiolata
at up to 63% of our study sites where λ
S
> 1, with the combination of both agents predicted to succeed at 88% of sites. Across sites and years, the elasticity rankings were dependent on λ. Reductions of rosette survival, fecundity, or germination of new seeds are predicted to cause the greatest reduction of λ in growing populations. In declining populations, transitions affecting seed bank survival have the greatest effect on λ. This contrasts with past analyses that varied parameters individually in an otherwise constant matrix, which may yield unrealistic predictions by decoupling natural parameter covariances. Overall, comparisons of stochastic and deterministic growth rates illustrate how analyses of individual populations or years could misguide management or fail to characterize complex traits such as invasiveness that emerge as attributes of populations rather than species.
Genetic alterations of ARID1B have been recently recognized as one of the most common mendelian causes of intellectual disability and are associated with both syndromic and non‐syndromic phenotypes. ...The ARID1B protein, a subunit of the chromatin remodeling complex SWI/SNF‐A, is involved in the regulation of transcription and multiple downstream cellular processes. We report here the clinical, genetic, and proteomic phenotypes of an individual with a unique apparent de novo mutation of ARID1B due to an intragenic duplication. His neurodevelopmental phenotype includes a severe speech/language disorder with full scale IQ scores 78–98 and scattered academic skill levels, expanding the phenotypic spectrum of ARID1B mutations. Haploinsufficiency of ARID1B was determined both by RNA sequencing and quantitative RT‐PCR. Fluorescence in situ hybridization analysis supported an intragenic localization of the ARID1B copy number gain. Principal component analysis revealed marked differentiation of the subject's lymphoblast proteome from that of controls. Of 3426 proteins quantified, 1014 were significantly up‐ or down‐regulated compared to controls (q < 0.01). Pathway analysis revealed highly significant enrichment for canonical pathways of EIF2 and EIF4 signaling, protein ubiquitination, tRNA charging and chromosomal replication, among others. Network analyses revealed down‐regulation of: (1) intracellular components involved in organization of membranes, organelles, and vesicles; (2) aspects of cell cycle control, signal transduction, and nuclear protein export; (3) ubiquitination and proteosomal function; and (4) aspects of mRNA synthesis/splicing. Further studies are needed to determine the detailed molecular and cellular mechanisms by which constitutional haploinsufficiency of ARID1B causes syndromic and non‐syndromic developmental disabilities.
The Asian tiger mosquito Aedes albopictus (Skuse) is rapidly increasing its global range and importance in transmission of chikungunya and dengue viruses. We tested pellet formulations of a ...monomolecular film (Agnique) and (S)-methoprene (Altosid) under laboratory and field conditions. In the laboratory, Agnique provided 80% control for 20 days, whereas Altosid, in combination with Agnique, provided 80% control for > 60 days. During field trials, the 1:1 pellet ratio of combined products provided > 95% control for at least 32 days and 50% control for at least 50 days. Altosid remained effective after a 107-day laboratory-induced drought, suggesting that the product serves as a means of control during drought conditions and against spring broods in temperate regions. Agnique and Altosid, when used in tandem for cryptic, difficult-to-treat locations, can provide long-term control of Ae. albopictus larvae and pupae. The possible additive or synergistic effects of the combined products deserve further investigation.
High temperatures and scarce precipitation often cause the productivity and quality of cool-season pastures in Southwest Michigan to decline for an extended period during the summer. This study was ...conducted to determine whether integration of switchgrass (Panicum virgatum L.) or big bluestem (Andropogon gerardii Vitm.) into cool-season grazing systems would mitigate this period of low pasture productivity and quality. Cool-season grass and legume pastures (CS-Only) were compared to integrated big bluestem and cool-season grass and legume pastures (CS-BBS) and integrated switchgrass and cool-season grass and legume pastures (CS-SG). The seasonal dynamics of forage dry matter offered, crude protein (CP), neutral detergent fiber (NDF), and acid detergent fiber (ADF) were used to compare the dynamics of the pasture productivity and quality in each of three treatments. Dry matter offered in the CS-Only treatment was higher earlier in the grazing season and the peak in dry matter-offered occurred between 20 and 30 d earlier in the CS-Only treatment than in the other treatments. The seasonal trend for CP was generally higher and more constant for the CS-Only treatment than for the CS-BBS and CS-SG treatments, which were very similar to each other. The seasonal trend for ADF and NDF was generally lower and more constant for the CS-Only treatment than for the CS-BBS and CS-SG treatments, which were very similar to each other. These findings suggest that, compared to the CS-Only treatment, the CS-SG or the CS-BBS treatments probably will not improve livestock gain or improve the distribution of animal grazing days throughout the summer.
Most biological traits are regulated by a complex interplay between genetic and environmental factors. By intercrossing divergent lines, it is possible to identify individual and interacting QTL ...involved in the genetic architecture of these traits. When the loci have been mapped, alternative strategies are needed for fine-mapping and studying the individual and interactive effects of the QTL in detail. We have previously identified, replicated, and fine mapped a four-locus QTL network that determines nearly half of the eightfold difference in body weight at 56 days of age between two divergently selected chicken lines. Here, we describe, to our knowledge, the first generation of a three-locus QTL introgression line in chickens. Recurrent marker-assisted backcrossing was used to simultaneously transfer QTL alleles from the low-weight selected line into the high-weight selected line. Three generations of backcrossing and one generation of intercrossing resulted in an introgression line where all three introgressed QTL and several unlinked and linked control-loci were segregating at nearly expected allele frequencies. We show how intensive selection can be applied using artificial insemination to rapidly generate a multi-locus introgression line and provide recommendations for future breeding of introgression lines. This confirmed introgression line will facilitate later detailed studies of the effects of genetic interactions on complex traits in this population, including growth, and body-composition traits.
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