Geospatial genetics: Integrating genetics into marine protection and spatial planning

1. The protection of evolutionary processes and maintenance of genetic diversity is necessary for the persistence of biodiversity and ecosystem resilience. The importance of genetic diversity has been reflected in a range of marine policy mechanisms, and the genetic ‘toolbox’ has great potential to support marine protection and marine spatial planning (MSP) at multiple scales. Despite scientific advances in the application of genetics in marine protection and management, systematic integration of genetic information has been generally lacking, primarily due to a knowledge and communication disconnect between geneticists and the marine policy and management community.
2. To meet these outstanding needs, a ‘geospatial genetics’ approach to spatially map species-specific genetic data and associated information in a way that can be readily integrated by practitioners into marine protection and MSP decisions was developed. Techniques to derive geospatial genetic data layers, which can be viewed and mapped alongside other kinds of spatial data commonly used by conservation practitioners, hold promise for increasing the accessibility of genetic data to support policy decisions more fully.
3. While applicable to many mobile and sessile taxa, an initial focus was placed on marine mammals, and the approach was developed and refined through a series of international meetings and published papers, as well as the development of interactive, expert-reviewed case studies hosted on the MSP tool SeaSketch.
4. Outcomes of the work to date are currently serving in the policy arena by informing the identification of Important Marine Mammal Areas, an initiative led by the IUCN Marine Mammal Protected Areas Task Force to apply criteria to identify marine mammal habitats across the world's ocean, seas and relevant inland waters through a standardized process.
5. It has become clear that geospatial genetics has great potential to foster increased collaboration among an intersectional community of geneticists, spatial ecologists, and practitioners. This increased opportunity for dialogue and cooperation will help ensure that evolutionary processes are factored into marine protection and MSP processes, and potentially for freshwater and terrestrial systems.

     

Frequency of 2n pollen in diploid hybrids betweenSolanum phureja Juz. & Buk. andSolanum chacoense Bitt.

Summary Solanum phureja (PP)xSolanum chacoense (CC) hybrid families (PC) were evaluated for pollen fertility and frequency of 2n pollen in two seasons in Morocco. PP clones produced high frequencies of 2n pollen, whereas CC clones produced none. The percentage of plants with 2n pollen ranged from 2 to 63% among 20 PC families and was consistent in some PC families over two growing seasons, whereas others varied between fall and spring growing seasons. The expected ratio of 2n to non-2n pollen-producers within a PC family based on a single recessive gene model [i.e. 1∶0 with CC homozygous dominant (PsPs) or 1∶1 with CC heterozygous (Psps)] was observed in only 5 of 20 progenies. Narrow sense heritability was 0.71, allowing gain from further selection. Only clones producing more than 10% 2n pollen exhibited more stable expressivity across seasons. Scientific Journal Series Article 17811 of the Minnesota Agricultural Experiment Station supported in part by the US Agency for International Development, contract no. 608-0160, IAV Morocco Project.     

Yield of embryos from sequential anther culture

Experiments were conducted on sequential anther culture,i.e., returning anthers into medium following the usual harvest of embryos six weeks after culture initiation. Three diploid interspecific hybrid potato clones were used. Additional embryos were produced after the first harvest, although the quality and regeneration frequency of such embryos were generally poorer than for first harvest embryos. In addition, embryos from the second harvest required more time to regenerate into plants. Significantly more embryos were produced when anthers were returned to the same medium (16 per flask) compared to fresh medium (4 per flask) in sequential anther culture. Regression analysis showed that embryo yields at the first and second harvests were significantly correlated (P<0.01). Poor anther culture yield at the first harvest was not caused by a longer lag period. Highly responsive cultures continued to yield embryos even 12 weeks after culture initiation.     

Effect of environment and direction of hybridization on genetic variability in two diploid potato populations

Summary Twelve selections from each of theSolanum tuberosum Groups haploid Tuberosum and Phureja were intercrossed in a NC Design II pattern to generate reciprocal hybrids. Yield parameters, combining ability and variance components were estimated from field experiments conducted at three locations, one in Minnesota and two in Morocco. Heterosis for yield and tuber number was significant at all locations, but only in Tuberosum cytoplasm. Estimates of general combining ability (GCA) for Tuberosum parents and specific combining ability (SCA) for Tuberosum-Phureja combinations varied with location and direction of hybridization. GCA of Phreja parents, however, was consistently significant at all locations and in both cytoplasms. Genetic variance estimates revealed predominantly non-additive gene action for most traits. Environment and direction of hybridization significantly influenced estimates, of variance components, indicating that hybrid performance should be evaluated in both cytoplasms and in the target environments for effective utilization of this germplasm in future breeding efforts. Scientific Journal Series Article 14,991 of the Minnesota Agricultural Experiment Station supported in part by the U.S. Agency for International Development, contract no. 608-0160, IAV Morocco Project.     

The effect of root and shoot pruning on early growth of hybrid poplars

Planting stock type and quality can have an important impact on early growth rates of plantations. The goal of this study was to evaluate early growth and root/shoot development of different planting materials in typical heavy clay soils of northwestern Quebec. Using one-year-old bareroot hybrid poplar dormant stock, four planting materials were compared: (1) regular bareroot stock, (2) rootstock (stem pruned before planting), (3) whips (roots pruned before planting), and (4) cuttings (30 cm stem sections taken from the basal portion of bareroot trees, i.e. roots and shoot pruned). Rooted stock types (bareroot and rootstock) produced, on average, 1.2 times larger trees than unrooted stock types (cuttings and whips). However, shoot-pruned stock types (rootstocks and cuttings) reached similar heights and basal diameters as unpruned stock types (bareroots and whips), during the first growing season. Shoot pruning reduced leaf carbon isotopic ratios, suggesting that unpruned stock types were water-stressed during the first growing season. The stress was most likely caused by early leaf development while root growth occurred later in the summer. We conclude that shoot pruning bareroot stock is a useful management option to reduce planting stress without compromising early growth rates of hybrid poplars.     

A Laboratory Assay for Phytophthora infestans Resistance in Various Solanum Species Reflects the Field Situation

Physiological and molecular research on resistance responses of Solanum tuberosum cultivars and partially resistant Solanum species to Phytophthora infestans requires a reliable resistance test that can be used in the laboratory. Laboratory tests performed on detached leaves and intact plants were compared with field tests for similarity of late blight reactions. Detached leaves from field-grown plants were as resistant as detached leaves from climate chamber-grown plants when challenged with P. infestans. However, detached leaves incubated in covered trays at high relative humidity were more susceptible than detached leaves kept in open trays or leaves on intact plants. The incubation conditions of detached leaves in covered trays rather than detachment itself appeared to affect the resistance expression. Detached leaves of some wild Solanum genotypes became partially infected, whereas intact plants were completely resistant when inoculated. Inoculation of leaves on intact plants, however, resulted in lower infection efficiencies. These limitations should be taken into account when choosing the appropriate inoculation method for specific purposes. For resistance screening, laboratory tests proved to be a good alternative for field tests. The ranking of resistance levels for twenty plant genotypes was similar under laboratory and field conditions.     

Escherichia coli EAST1 toxin toxicity of variants 17-2 and O 42

EAST1 (EnteroAggregative heat-Stable Toxin 1) is a 4.1 kDa toxin that was first detected in the enteroaggregative Escherichia coli (EAEC) strain 17-2 (O3:H2) isolated from the stools of a Chilean child with diarrhoea. Accordingly, EAST1 is thought to play a role in the pathogenicity of EAEC. The goal of this study was to obtain purified biologically active forms of two EAST1 variants (17-2 and O 42). Purified toxin samples were treated with protein disulfide isomerase (PDI) to ascertain the integrity of the disulfide bridges. Since EAST1 is often compared to STa (heat-Stable Toxin a), both purified EAST1 variants were tested for biological activity using the suckling mouse assay, the reference test for STa. A positive gut to body (G/B) weight ratio was not observed for any of the EAST1 preparations tested, although STa was active. Exposure of the purified toxins to T84 cell monolayers, an epithelial cell line derived from a human colon carcinoma, in modified Ussing flux chambers resulted in a rapidly attained and prolonged increase in short circuit current, a sensitive measure of net ion transport. Responses to 17-2 and O 42 variants were comparable in magnitude and inhibitable by bumetanide and DASU-02, indicating net anion secretion. The results demonstrate that EAST1 toxin stimulates anion secretion by T84 cell monolayers and it is sustained for the duration of toxin exposure.     

Presence of Escherichia coli carrying the EAST1 toxin gene in farm animals

Enteroaggregative Escherichia coli (EAEC) heat-stable toxin 1 (EAST1) is a small toxin of proteic nature. The reference strain producing this toxin was originally detected in the stools of a diarrheic Chilean child. Today, we know that EAST1 is not solely associated with EAEC but also with many other diarrheic E. coli families. Some studies have established the role of EAST1 in human outbreaks of diarrhea. In addition, isolates from farm animals were shown, more recently, to carry the astA gene coding for EAST1. However, the relation between the presence of EAST1 and disease is not conclusive. In this article, the current state of the knowledge on the presence and probable role of EAST1 in farm animal diseases is reviewed and discussed.     

Breeding behavior of yield components and hollow heart in tetraploid-diploid vs. conventionally derived potato hybrids

Summary A factorial mating design with six 4x cultivars as stylar parents mated to three groups of pollen parents (4x cultivars, 4x high protein selections, and 2x S. phureja) was used to study breeding behavior of yield, tuber set, marketable yield and hollow heart in potatoes. Mean yield for the 4x-2x hybrids was equivalent to that of their cultivar parents although yield components, tuber set and average tuber size, were greater and less, respectively, than the cultivar parents. High estimates of general combining ability were found in both pollen and stylar parents for yield, tuber set, marketable yield, number of marketable tubers and hollow heart in all three hybrid populations. Specific combining ability estimates were significant only for yield and hollow heart. Frequency of white-fleshed 4x-2x progeny of five heterozygous yellow-fleshed 2x phureja genotypes was used to confirm cytological identification of a first division restitution mechanism operative in the 2x parents. Although three of these phureja genotypes generated high-yielding progeny, two others produced 4x-2x progeny with mean yield similar to that of hybrids among 4x cultivars.Scientific journal series article 11,601 of the Minnesota Agricultural Experiment Station.     

Bioavailability and Tolerability of Topical and Oral Diclofenac Sodium Administration in Healthy Ponies

Aiming to characterize the bioavailability and assess the safety of topical and oral treatment of diclofenac sodium in healthy ponies, 18 animals were divided in three groups: one treated with topical (group I, n = 6), the second with oral diclofenac (group II, n = 6) at 2.5 mg/kg for 3 days, and the third group received 2.2 mg/kg oral phenylbutazone (group III, n = 6) also for 3 days to serve as positive control. To evaluate bioavailability, blood samples were collected before and at 0, 0.5, 1, 3, 6, 9, 12, 24, 36, 48, 60, 72, 96, 120, and 144 hours after starting treatment. To evaluate diclofenac sodium concentration in the synovial fluid, samples of six ponies (group I, n = 3; group II, n = 3) were collected at 6, 12, and 24 hours after starting the treatment.