Tuberculous mastoiditis - a case series.

SUMMARY: Tuberculous mastoiditis (TBM) is a rare form of extrapulmonary tuberculosis (TB), which may result in catastrophic complications, including mastoid and ossicle destruction, hearing loss and intracranial spread if untreated. Diagnosis is challenging due to the paucibacillary nature of extrapulmonary TB, compounded by limited theatre access for specimen retrieval, resulting in delayed diagnosis and treatment initiation. In this case series, we discuss three cases of TBM (one paediatric and two adults) who presented to the public and private healthcare sectors in the Eastern Cape in 2022, underscoring that TB does not respect socioeconomic status.

Ediacaran metazoan reveals lophotrochozoan affinity and deepens root of Cambrian Explosion.

Through exceptional preservation, we establish a phylogenetic connection between Ediacaran and Cambrian metazoans. We describe the first three-dimensional, pyritized soft tissue in Namacalathus from the Ediacaran Nama Group, Namibia, which follows the underlying form of a stalked, cup-shaped, calcitic skeleton, with six radially arranged lobes projecting into an apical opening and lateral lumens. A thick body wall and probable J-shaped gut are present within the cup, and the middle layer of the often-spinose skeleton and skeletal pores are selectively pyritized, supporting an organic-rich composition and tripartite construction with possible sensory punctae. These features suggest a total group lophotrochozoan affinity. These morphological data support molecular phylogenies and demonstrates that the origin of modern lophotrochozoan phyla, and their ability to biomineralize, had deep roots in the Ediacaran.

Regional nutrient decrease drove redox stabilisation and metazoan diversification in the late Ediacaran Nama Group, Namibia.

The late Ediacaran witnessed an increase in metazoan diversity and ecological complexity, marking the inception of the Cambrian Explosion. To constrain the drivers of this diversification, we combine redox and nutrient data for two shelf transects, with an inventory of biotic diversity and distribution from the Nama Group, Namibia (~550 to ~538 Million years ago; Ma). Unstable marine redox conditions characterised all water depths in inner to outer ramp settings from ~550 to 547 Ma, when the first skeletal metazoans appeared. However, a marked deepening of the redoxcline and a reduced frequency of anoxic incursions onto the inner to mid-ramp is recorded from ~547 Ma onwards, with full ventilation of the outer ramp by ~542 Ma. Phosphorus speciation data show that, whilst anoxic ferruginous conditions were initially conducive to the drawdown of bioavailable phosphorus, they also permitted a limited degree of phosphorus recycling back to the water column. A long-term decrease in nutrient delivery from continental weathering, coupled with a possible decrease in upwelling, led to the gradual ventilation of the Nama Group basins. This, in turn, further decreased anoxic recycling of bioavailable phosphorus to the water column, promoting the development of stable oxic conditions and the radiation of new mobile taxa.

Low levels of hybridization in two species of African driver ants.

Hybridization in ants can have consequences different from those observed in most other species, with many of the potential deleterious effects being mitigated due to haplodiploidy and eusociality. In some species where colonies are either headed by multiple queens or single queens that mate with many males, hybridization is associated with genetic caste determination, where hybrids develop into workers and purebred individuals develop into queens. A previous study suggested that hybridization occurs between two Dorylus army ant species with multiply mated queens. However, the extent and exact pattern of hybridization have remained unclear, and its possible effect on caste determination has not been investigated. In this study, we aimed to determine the extent and direction of hybridization by measuring how frequently hybrids occur in colonies of both species, and to investigate the possibility of genetic caste determination. We show that hybridization is bidirectional and occurs at equal rates in both species. Hybrid workers make up only 1-2% of the population, and successful interspecific matings represent approximately 2% of all matings in both species. This shows that, although interspecific matings that give rise to worker offspring occur regularly, they are much rarer than intraspecific mating. Finally, we find no evidence of an association between hybridization and genetic caste determination in this population. This means that genetic caste determination is not a necessary outcome of hybridization in ants, even in species where queens mate with multiple males.

Monitoring long-term evolution of engineered barrier systems using magnets: Magnetic response.

Remote and non-destructive monitoring of the stability and performance of Engineered Barrier Systems for Geological Disposal Facility of is gaining considerable importance in establishing the safety cases for Higher Activity Wastes disposal. This study offers an innovative use of mineral magnetism for monitoring groundwater saturation of the barrier. Four mixtures of permanent magnets (Nd-Fe-B, coated and uncoated; SmCo and AlNiCo) and bentonite were reacted for 4, 8 and 12 months with mildly-saline, high-pH leachates, representing the fluids saturating a time-evolved engineered barrier. Coupled hysteresis and thermomagnetic analyses demonstrate how Nd-Fe-B feature a time-dependent transition from square-like ferromagnetic to superparamagnetic loop via pot-bellied and wasp-waist loops, whereas SmCo and AlNiCo do not show so extensive corrosion-related variations of the intrinsic and extrinsic magnetic properties. This study allowed to identify magnetic materials suitable for shorter- (Nd-Fe-B) and longer-term (SmCo and AlNiCo) monitoring purposes.

Extracranial internal carotid artery pseudoaneurysm in a two-year-old child: case report.

BACKGROUND: Extracranial internal carotid artery pseudoaneurysm is very rare in children. METHOD: This paper discusses the case of a boy, aged two years and six months, who presented with an enlarging neck mass and unilateral bloody otorrhoea. Special investigations revealed an extracranial internal carotid artery pseudoaneurysm. RESULTS: The patient made a full recovery after endovascular occlusion of the internal carotid artery and pseudoaneurysm using coils. At six months' follow up, the internal carotid artery and pseudoaneurysm remained excluded from the circulation. The patient did not display any neurological deficits during hospital stay or follow up. CONCLUSION: This paper reports on one of the youngest patients documented to date who presented with an internal carotid artery pseudoaneurysm, possibly secondary to ear infection. Although rare, this condition should be excluded in children presenting with a mass of the neck or pharynx because of the dire consequences if left undiagnosed and untreated.

Age of diagnosis of congenital hearing loss: Private v. public healthcare sector.

BACKGROUND: The age of diagnosis of congenital hearing loss is one of the most important determinants of communication outcome. A previous study by the lead author had evaluated the performance of the public health services in Bloemfontein, South Africa (SA), in this regard. This study aimed to examine whether the private health services in the same city were any better. OBJECTIVE: To determine whether the age of diagnosis of congenital hearing loss (CHL) in children seen in the private healthcare sector in Bloemfontein, Free State Province, SA, was lower than that in the public healthcare system in the same city. METHODS: A comparative study design was utilised and a retrospective database review conducted. Data obtained from this study in the private healthcare sector were compared with data from a previous study in the public healthcare sector using the same study design. RESULTS: Forty-eight children aged <6 years with disabling hearing impairment (DHI) were identified in the private healthcare sector during the study period; 33/47 (70.2%) did not undergo hearing screening at birth. The median age of diagnosis of DHI in the private healthcare sector was 2.24 years, and this was statistically significantly lower than the median age of diagnosis of 3.71 years in the public healthcare sector (p<0.0001; 95% confidence interval (CI) 0.99-2.0). The median age of diagnosis of congenital hearing loss (CHL) in the private healthcare sector was 3.01 years in children who were not screened at birth, and 1.25 years in those who were screened at birth. This difference was statistically significant (p<0.01; 95% CI 0.72-2.47). We also compared the median age of diagnosis of CHL in children from the private healthcare sector who were not screened at birth (median 3.01 years) with that in children in the public healthcare sector (median 3.71 years). This difference was statistically significant (p<0.01; 95% CI 0.41-1.56). CONCLUSIONS: Children in the Free State are diagnosed with CHL at a younger age in the private healthcare sector than in the public healthcare sector. With the social and economic benefits of early intervention in cases of DHI well established internationally, SA healthcare providers in both the public and private sectors need to develop screening, diagnostic and (re)habilitation services for children with hearing impairment.

The influence of biofilms on the mobility of bare and capped zinc oxide nanoparticles in saturated sand and glass beads.

Biofilms are a common constituent of the subsurface and are known to influence contaminant transport; however only a few studies to date have addressed microbial controls on nanoparticle mobility in porous media. The impact of a 3-day Pantoea agglomerans biofilm on the mobility of zinc oxide (ZnO) nanoparticles was studied in column experiments containing sand and glass beads at near-neutral pH and constant ionic strength. Bare ZnO nanoparticles (bZnO-NPs) and ZnO nanoparticles capped with tri-aminopropyltriethoxysilane (cZnO-NPs) were used in the experiments. Breakthrough curves demonstrate that the biofilm particularly slowed nanoparticle migration of bZnO-NPs in glass bead columns and cZnO-NPs in sand columns. With the exception of bZnO-NPs in sand columns, biofilm-coated porous media retained more nanoparticles than those of controls without biofilm. The biofilm may bear an impact on the surface charge of the porous medium, nullifying porous medium-specific effects. Although viable cell counts (VCCs) decreased after the introduction of electrolyte and before nanoparticle transport experiments, SEM and CLSM imaging of porous medium samples taken from columns after nanoparticle transport experiments, as well as total organic carbon (TOC) measurements reveal that biofilm was present in the columns throughout the experiments. Hence, it can be concluded that even a thin amount of biofilm can hinder nanoparticle migration in small-scale porous medium experiments. Moreover, nanoparticle mobility is dependent on the binding capacity of biofilms, rather than the type of porous media.

The cumulative impacts of repeated heavy rainfall, flooding and altered water quality on the high-latitude coral reefs of Hervey Bay, Queensland, Australia.

Terrestrial runoff and flooding have resulted in major impacts on coral communities worldwide, but we lack detailed understanding of flood plume conditions and their ecological effects. Over the course of repeated flooding between 2010 and 2013, we measured coral cover and water quality on the high-latitude coral reefs of Hervey Bay, Queensland, Australia. In 2013, salinity, total suspended solids, total nitrogen and total phosphorus were altered for up to six months post-flooding. Submarine groundwater caused hypo-saline conditions for a further four months. Despite the greater magnitude of flooding in 2013, declines in coral abundance (∼28%) from these floods were lower than the 2011 flood (∼40%), which occurred immediately after a decade of severe drought. There was an overall cumulative decrease of coral by ∼56% from 2010 to 2013. Our study highlights the need for local scale monitoring and research to facilitate informed management and conservation of catchments and marine environments.

Transport of bare and capped zinc oxide nanoparticles is dependent on porous medium composition.

Zinc oxide (ZnO) nanoparticles are one of the most frequently used nanoparticles in industry and hence are likely to be introduced to the groundwater environment. The mobility of these nanoparticles in different aquifer materials has not been assessed. While some studies have been published on the transport of ZnO nanoparticles in individual porous media, these studies do not generally account for varying porous medium composition both within and between aquifers. As a first step towards understanding the impact of this variability, this paper compares the transport of bare ZnO nanoparticles (bZnO-NPs) and capped ZnO nanoparticles, coated with tri-aminopropyltriethoxysilane (cZnO-NPs), in saturated columns packed with glass beads, fine grained sand and fine grained calcite, at near-neutral pH and groundwater salinity levels. With the exception of cZnO-NPs in sand columns, ZnO nanoparticles are highly immobile in all three types of studied porous media, with most retention taking place near the column inlet. Results are in general agreement with DLVO theory, and the deviation in experiments with cZnO-NPs flowing through columns packed with sand is linked to variability in zeta potential of the capped nanoparticles and sand grains. Therefore, differences in surface charge of nanoparticles and porous media are demonstrated to be key drivers in nanoparticle transport.

Paediatric chronic suppurative otitis media in the Free State Province: clinical and audiological features.

BACKGROUND: Chronic suppurative otitis media (CSOM) is a chronic infection of the middle ear cleft. In sub-Saharan Africa >50% of cases occur in children <10 years of age. OBJECTIVES: To describe the otological, audiological and bacteriological findings in children with CSOM. METHODS: We conducted a prospective study at the Ear, Nose and Throat (ENT) Clinic at Universitas Academic Hospital between August 2009 and December 2010. We included all children with CSOM over this period. Patients underwent ENT and paediatric examination, and were tested for HIV. Pus swabs were taken after an ear toilet for routine microbiology, fungal and Mycobacterium tuberculosis culture. We performed audiological testing after the otorrhoea had resolved. RESULTS: Eighty-six children (113 ears) were included, with a median age of 4.6 years (range 1 - 12 years). The mean duration of otorrhoea was 161.7 weeks (range 4 - 572 weeks). Nine patients (10.5%) presented with coalescent mastoiditis and/or intracranial complications of CSOM. Of the 153 organisms identified; Gram-negative bacteria were present in 93 (82.3%) ears, with 94.8% of these being sensitive to quinolones. Only 1 case of tuberculous otitis media was identified. HIV infection was present in 54.6% of patients tested. There was a hearing loss in 44 (66.7%) of the tested affected ears. CONCLUSIONS: There was a long delay between the onset of symptoms and accessing ENT services. Most cases of CSOM were due to quinolone-sensitive Gram-negative aerobes. There was a high prevalence of cholesteatoma, hearing loss and other complications in children in this study.

Age of diagnosis of congenital hearing loss at Universitas Hospital, Bloemfontein.

BACKGROUND: Congenital hearing loss affects 3 - 6/1 000 children worldwide. The benefits of early identification of hearing loss and early intervention have been clearly established. There are no previous studies reporting on the age of diagnosis of congenital hearing loss in the Free State province. OBJECTIVES: To determine the age of diagnosis of congenital hearing loss in the Otorhinolaryngology Clinic at Universitas Hospital. Secondary aims included determining age at first visit, as well as the time delay between first visit and diagnosis, and documenting any interventions which took place. METHODS: A retrospective, descriptive study was undertaken, analysing data from 2001 to 2010. RESULTS: A total of 260 cases of congenital hearing loss were analysed. The median age of diagnosis of hearing loss was 44.5 months. The median age of first visit was 40.9 months, and the median delay between first visit and diagnosis was 49 days. CONCLUSIONS: The median age of diagnosis far exceeds national and international benchmarks. This has a profoundly negative impact on the development and outcomes of children with hearing loss. These results have been used to motivate for the expansion of hearing screening and diagnostic services in the province.

Lancefield group G Streptococcus dysgalactiae subsp. equisimilis: an unusual aetiology of perianal streptococcal dermatitis acquired from heterosexual oral-anal intercourse.

Perianal streptococcal dermatitis (PSD) is an uncommon superficial cutaneous infection of the perianal area, almost exclusively described in children and mainly caused by group A streptococci. We report here a case of PSD caused by Streptococcus dysgalactiae subsp. equisimilis, Lancefield group G, in an adult man due to heterosexual oral-anal sexual contact.

Synthesis, structural characterization and in vitro inhibitory studies against human breast cancer of the bis-(2,6-di-tert-butylphenol)tin(IV) dichloride and its complexes.

Four new organotin(IV) complexes of bis-(2,6-di-tert-butylphenol)tin(IV) dichloride [(tert-Bu-)(2)(HO-Ph)](2)SnCl(2) (1) with the heterocyclic thioamides 2-mercapto-pyrimidine (PMTH), 2-mercapto-4-methyl-pyrimidine (MPMTH), 2-mercapto-pyridine (PYTH) and 2-mercapto-benzothiazole (MBZTH), of formulae {[(tert-Bu-)(2)(HO-Ph)](2)Sn(PMT)(2)} (2), {[(tert-Bu-)(2)(HO-Ph)](2)Sn(MPMT)(2)} (3), {[(tert-Bu-)(2)(HO-Ph)](2)SnCl(PYT)} (4) and {[(tert-Bu-)(2)(HO-Ph)](2)SnCl(MBZT)} (5), have been synthesized and characterized by elemental analysis, (1)H-, (13)C-, (119)Sn-NMR, EPR, FT-IR, Raman and Mössbauer spectroscopic techniques. The crystal and molecular structures of compounds 1­5 have been determined by X-ray diffraction. The geometries around the metal center adopted in complexes 1­5 varied between tetrahedral in 1, trigonal bipyramidal in 3, 4, 5 and distorted octahedral in 2. Two carbon atoms from aryl groups and two chlorine atoms form a distorted tetrahedron in the case of 1. Two carbon, two sulfur and two nitrogen atoms from thione ligands form a distorted octahedral geometry around tin(IV) with trans-C(2), cis-N(2), cis-S(2)-configurations in 2. However, in the case of 4 and 5 complexes two carbon, one sulfur, one nitrogen and one chloride atom form a distorted trigonal bipyramidal arrangement. Finally, in the case of 3 the trigonal bipyramidal geometry is achieved by two carbon, two sulfur and one nitrogen atom in a unique coordination mode of thioamides toward the tin(IV) cation. Compounds 1­5 were tested for their in vitro cytotoxicity against the human breast adenocarcinoma (MCF-7) cell line. Compound 3 exhibits strong cytotoxic activity against MCF-7 cells (IC(50) = 0.58 ± 0.1 µM).

Structural motifs and biological studies of new antimony(III) iodide complexes with thiones.

Eight new antimony(III) iodide complexes of the heterocyclic thioamides, 2-mercapto-1-methylimidazole (MMI), 2-mercaptobenzimidazole (MBZIM), 5-ethoxy-2-mercaptobenzimidazole (EtMBZIM), 2-mercaptothiazolidine (MTZD), 3-methyl-2-mercaptobenzothiazole (NMeMBZT), 2-mercapto-3,4,5,6-tetrahydropyrimidine (tHPMT), 2-mercaptopyridine (PYT), and 2-mercaptopyrimidine (PMT) of formulas {[SbI(3)(MMI)(2)].MeOH} (1), [SbI(3)(MBZIM)(2)] (2), {[SbI(2)(mu(2)-I)(EtMBZIM)(2)](2).H(2)O} (3), [SbI(3)(MTZD)] (4), [(NMeMBZT)SbI(2)(mu(2)-I)(2)(mu(2)-S-NMeMBZT)SbI(2) (NMeMBZT)] (5), {[SbI(3)(tHPMT)(3)].MeOH} (6), [SbI(3)(PYT)] (7), and [SbI(3)(PMT)(2)] (8), have been synthesized and characterized by elemental analysis, FT-IR spectroscopy, FT-Raman spectroscopy, and TG-DTA analysis. The crystal structures of 3, 4, 5, 6, and 7 were also determined by X-ray diffraction. The complexes show interesting structural motifs. Complex 6 is a monomer, with octahedral (Oh) geometry around the metal ion formed by three sulfur and three iodide atoms. Complexes 3 and 5 are dimers, with a square pyramidal (SP) geometry in each monomeric unit, while complexes 4 and 7 are polymers with pseudotrigonal bipyramidal (psi-TBP). Two or three sulfur atoms from thioamide ligands and three iodide atoms are bound to Sb atoms forming building blocks for the dimers and polymers. Strong intramolecular interactions between mu(2)-I and/or mu(2)-S and Sb atoms stabilize both structures. In dimer complex 5, two terminal iodide and one terminal sulfur atom are bonded to the Sb ion, while two mu(2)-I and one mu(2)-S bridging atoms bridge the metal ions forming psi-Oh geometry. Computational studies using multivariant linear regression (MLR) and artificial neural networks (ANN) and considering biological results (50% inhibitory concentration, IC(50)) as dependent variables derived a theoretical equation for IC(50) values of the complexes studied. The calculated IC(50) values are compared satisfactorily with the experimental inhibitory activity of the complexes measured. Complexes 3-7 were used to study their influence upon the catalytic peroxidation of linoleic acid by the enzyme Lipoxygenase (LOX). Compounds 1-8 were also tested for in vitro cytotoxicity, and they showed mostly a moderate cytostatic activity against a variety of tumor cell lines but comparable with those found for the antimony(III) chloride and bromide complexes, reported earlier [Ozturk et al. Inorg. Chem. 2007, 46, 2861-2866; Ozturk et al. Inorg. Chem. 2009, 48, 2233-2245].

Coordination chemistry of tetra- and tridentate ferrocenyl polyphosphines: an unprecedented [1,1'-heteroannular and 2,3-homoannular]-phosphorus-bonding framework in a metallocene dinuclear coordination complex.

PalladiumII and nickelII halide complexes of the ferrocenyl polyphosphines 1,1',2,3-tetrakis(diphenylphosphino)ferrocene (1), and 1,1',2-tris(diphenylphosphino)-4-tert-butylferrocene (5) were prepared and characterized by multinuclear NMR. The metallo-ligand 1, the palladium [Pd2Cl4(1)] (3b) and nickel [NiCl2(5)] (6) coordination complexes were additionally characterized by X-ray diffraction crystallography. The behavior of 1 toward coordination to nickel and palladium was surprisingly different because the coordination of a second metal center after the initial 1,2-phosphorus-bonding of nickel was markedly difficult. The preference of nickel for 1,2-P coordination on 1,1'-bonding was confirmed by the exclusive formation of 6 from 5. The changes noted between the solid state structure of the ligand 1 and the structure obtained for the dinuclear palladium complex 3b reveal the rotational flexibility of this tetraphosphine. This flexibility is at the origin of the unique framework for a metallocenic dinuclear metal complex in which both coexist a 1,1'-heteroannular chelating P-bonding and a 2,3-homoannular chelating P-bonding with two palladium centers. Some reported specimens of ferrocenyl polyphosphines of constrained geometry have previously revealed that phosphorus lone pair overlap can lead to very intense "through-space" 31P31P nuclear spin-spin coupling constants (JPP) ( J. Am. Chem. Soc. 2004, 126 (35), 11077-11087] in solution phase. In these cases, an internuclear distance between heteroannular phosphorus atoms below 4.9 A, with an adequate orientation of the lone-pairs in the solid state and in solution, was a necessary parameter. The flexibility of the new polyphosphines 1 and 5 does not allow that spatial proximity (internuclear distances between heteroannular phosphorus above 5.2 A in the solid state); accordingly the expected through-space nuclear spin-spin coupling constants were not detected in any of their coordination complexes nor in 1.

Coordination properties of Cu(II) and Ni(II) ions towards the C-terminal peptide fragment -TYTEHA- of histone H4.

In order to reveal more information about the toxicity caused by metals and furthermore their influence to the physiological metabolism of the cell, the hexapeptide model Ac-ThrTyrThrGluHisAla-am representing the C-terminal 71-76 fragment of histone H4 which lies into the nucleosome core, was synthesized. A combined pH-metric and spectroscopic UV-VIS, EPR, CD and NMR study of Ni(II) and Cu(II) binding to the blocked hexapeptide, revealed the formation of octahedral complexes involving imidazole nitrogen of histidine, at pH 5 and pH 7 for Cu(II) and Ni(II) ions respectively. In basic solutions a major square-planar 4 N Ni(II)-complex, adopting a {N(Im), 3N(-)} coordination mode, was formed. In the case of Cu(II) ions, a 3 N complex, involving the imidazole nitrogen of histidine and two deprotonated amide nitrogens of the backbone of the peptide, at pH 7 and a series of 4 N complexes starting at pH 6.5, were suggested. In addition Ni(II)-mediated hydrolysis of the peptide bond-Tyr-Thr was evident following our experimental data.

Thermal decomposition studies of the polyhedral oligomeric silsesquioxane, POSSh, and when it is impregnated with the metallocene bis(eta5-cyclopentadienyl)zirconium (IV) dichloride or immobilized on silica.

Thermal decomposition studies of the free polyhedral oligomeric silsesquioxane, POSSh, and when this compound has been impregnated with Cp2ZrCl2 (Cp = eta5-C5H5) or immobilized on SiO2 were conducted using infrared emission spectroscopy (IES) over a 100-1000 degrees C temperature range and by thermogravimetric analysis (TGA). The organic groups in POSS(h) apparently decompose thermally into Si-CH3, Si-H and other fragments. Upon impregnation with Cp2ZrCl2, however, a different thermal decomposition pathway was followed and new infrared emission bands appeared in the 1000-900 cm(-1) region suggesting the formation of Si-O-Zr moieties. When immobilized on SiO2 and subjected to thermal decomposition, the POSSh compound lost its organic groups and the inorganic structure remaining was incorporated into the SiO2 framework.

Synthesis of erbium hydroxide microflowers and nanostructures in subcritical water.

The effects of temperature, pressure, pH, residence time and reactant concentrations, as well as the presence or absence of CO(2), on the size and morphology of erbium hydroxide particles synthesized in a hydrothermal batch reactor and a diamond-anvil cell (DAC) reactor have been investigated. Several new erbium-based microstructures and nanostructures were obtained that encompass different phases and shapes, including crystalline microflowers, hexagonal microlayers, microsticks and microspheres made from nanoparticles, as well as nanofibers, nanorods and nanolayers. The Er(2)OCO(3)(OH)(2) microflowers are pure, structurally uniform, and mostly free from dislocations. Their crystallinity, morphology, optical properties and structural features have been examined and compared with those of the other phases by field-emission scanning electron microscopy (SEM), x-ray diffraction (XRD), and energy-dispersive x-ray (EDX) analysis, and by Raman, infrared, UV-visible and fluorescence spectroscopy.

Analyses of a multi-parent population derived from two diverse alfalfa germplasms: testcross evaluations and phenotype-DNA associations.

In a previous study, we showed that the genetic variation present in the Medicago sativa subsp. sativa Peruvian and M. sativa subsp. falcata WISFAL germplasms could be used to improve forage yields when favorable alleles were recombined and used in hybrid combination with cultivated alfalfa. In this paper, we present testcross forage yield and fall growth data for two seasons of a C0 population generated after intermating the Peruvian x WISFAL population for several generations. In addition, we conducted marker-trait association analysis as an attempt to identify Peruvian and WISFAL genomics regions affecting the targeted traits. Five and seven genomic regions were found significantly associated with forage yield and fall growth, respectively. In the case of fall growth, alleles from both accessions were positively associated with plant height. However, more alleles from WISFAL were positively associated with forage yield than from Peruvian. WISFAL is known for its winter hardiness and genomic regions with large effects on winter survival may have masked the effect of forage yield from Peruvian. The fact that most of the genomic regions discovered in this study have been previously associated with traits involved in winter hardiness validates our findings and suggests that associations between DNA fragments and agronomic traits can be detected without the necessity of developing bi-parental mapping populations.