Miracle-dz/UniFAR-FTUs huggingface dataset:
Genetics and resistance / Génétique et résistance Physiologic specialization of wheat leaf rust (Puccinia triticina) in Canada in 2002

Forty virulence phenotypes of Puccinia triticina were identified from 295 isolates collected across Canada in 2002 on 16 Triticum aestivum ‘Thatcher’ near-isogenic lines. The most frequent virulence phenotypes across Canada were MBDS (30.2%), TGBJ (22.0%), TBBJ (9.5%), and TBDS (7.8%). There were 10 virulence phenotypes identified among 24 isolates from Quebec; MBRK (29.2%), TBRJ (16.7%), MBRJ (12.5%), and TLGJ (12.5%) were the most frequent. Ten virulence phenotypes were identified among 22 isolates from Ontario, with PCLR and PCMR (both 22.7%) being the most frequent. There were 25 virulence phenotypes identified from 234 isolates collected in Manitoba and southeastern Saskatchewan; MBDS (32.9%), TGBJ (27.4%), and TBBJ (11.5%) were the most frequent. The frequency of virulence to Lr16 declined in Manitoba and Saskatchewan from 74.1% in 2001 to 33.3% in 2002 while the frequency of virulence to Lr17 increased from 23.8% in 2001 to 53.4% in 2002. Five virulence phenotypes were identified from 15 isolates collected in Alberta. These were MBDS (11 isolates), TBBJ, TBDS, TCRK, and TGBJ (all one isolate each). A subsample representative of the field isolates collected in 2002 was tested for virulence on adult plants. All 71 isolates tested were avirulent to adult-plant resistance genes Lr22a, Lr34, and Lr3, and to seedling genes Lr21 and Lr32 which are best expressed in adult plants. The isolates varied for virulence to adult-plant resistance genes Lr12 and Lr37, and only one isolate was avirulent to Lr13.
Evidence for gravitactic behaviour in benthic diatoms

Vertical migration by diatoms is a well-known phenomenon, occurring in intertidal and subtidal benthic biofilms. It is partially endogenously driven, as cell movements can be observed in the absence of external stimuli such as light, temperature or water cover. Although vertical migration of diatoms under constant conditions has often been attributed to geotactic orientation, this hypothesis has never been experimentally demonstrated. Our study tested the gravitactic nature of the vertical migratory behaviour of benthic diatoms in sedimentary biofilms, using an experimental setup designed to distinguish gravitaxis from surface-oriented cell movements. The hourly variation of surface diatom biomass during migratory cycles was compared in homogenized sediment samples kept facing upwards (surface-oriented and gravity stimuli coinciding; controls) and facing sideways or downwards (surface-oriented and gravity stimuli not coinciding). During the experiments, sediment samples were kept in complete darkness in custom-made, sealed measuring chambers designed to avoid any contact with atmospheric air and the formation of physico-chemical gradients near the surface. Microalgal biomass was monitored non-intrusively using PAM fluorometry, by measuring dark-level fluorescence, Fo. The results showed a clear effect of sample orientation in relation to the gravitational stimulus. In the controls, a biphasic pattern in surface biomass was observed, with the formation of a clear biomass peak (three- to six-fold increase) followed by a slower decrease. In contrast, in samples facing sideways or downwards, surface biomass also varied but to a much lesser extent (typically < two-fold). These results strongly suggest that, in the absence of light, upward vertical migration of benthic diatoms is mostly guided by negative gravitaxis, supporting the often hypothesized capacity of these cells to sense and use gravity to move vertically within the sediment.
Tillage, Crop Sequence, and Cultivar Effects on Sclerotinia Stem Rot Incidence and Yield in Soybean

al., 1999; Pennypacker and Risius, 1999). Management practices—including narrow row spacing, increased Sclerotinia stem rot (SSR), caused by Sclerotinia sclerotiorum plant populations, early planting dates, and high soil (Lib.) de Bary, is an important soybean [Glycine max (L.) Merr. ] disease in the North Central States. The effect of tillage, crop se- fertility—that are intended to increase soybean yields, quence, and cultivar on SSR incidence and soybean yield was evalu- create favorable conditions for SSR development within ated in a 3-yr on-farm study conducted at Janesville, Sharon, and the crop canopy (Pennypacker and Risius, 1999). ShortWaunakee, WI. In the study, arranged in a split-split-split-split plot ened crop sequences, frequently limited to corn and design, main plots were tillage: moldboard (MB), chisel plow (CP), soybean, reduced tillage, or rotation with susceptible or no-till (NT); subplots were 1995 crops: corn (Zea mays L.), small crops such as sunflower (Helianthus annuus L.), canola grain, or soybean; sub-subplots were 1996 crops: corn, small grain, or (Brassica rapa L.), or dry bean (Phaeseolus vulgaris L.) soybean cultivar. Sub-sub-subplots were soybean cultivars planted increase soil inoculum density (Schwartz and Steadman, in 1997. In 1997, SSR incidence averaged 40% at Janesville and 1978). Above normal precipitation and lower temperaWaunakee, and 1% at Sharon; and was lowest in NT (P 0.001) tures occurring during the critical infection period folor when the soybean cultivar S19-90 was planted (P 0.001). Planting
Tillage and Straw Management Impacts on Soil Properties, Root Growth, and Grain Yield of Winter Wheat in Northwestern China

Studies on root development, soil physical properties, and yield are important for identifying suitable soil management practices for sustainable crop production. Field experiments with winter wheat (Triticum aestivum L.) were conducted in silt loam soil from 2005 through 2007 in arid northwestern China to determine the effects of five tillage systems on soil strength, soil moisture, crop root development, grain yield, and yield components. The five treatments were conventional tillage without wheat stubble (T), conventional tillage with wheat stubble incorporated (TSI), no-tillage without wheat stubble mulching (NT), no-tillage with wheat stubble standing (NTSS), and no-tillage with wheat stubble mulching (NTS). Compared with the T treatment, the NTSS and NTS treatments improved soil water content in the 0- to 130-cm soil depth by 10 to 17% and 15 to 25%, respectively (P < 0.05). The NTSS treatment also increased mean root length density (RLD) by 8 to 40% and crop yield by 13 to 24%, and NTS by 17 to 48% and 17 to 31%, compared with the T treatment. Yield components analysis indicated that thousand-grain weight and spike density considerations helped explain the grain yield increases under conservation tillage systems (NT, NTSS, NTS), while spike length, number of grains per spike, and grain weight per spike failed to contribute to the model. Our results suggest that Chinese farmers should consider adopting conservation tillage practices in arid northwestern China because of benefits to soil strength, water storage, RLD, and wheat yield.
Effect of seawater on Escherichia coli β-galactosidase activity

An investigation of beta-galactosidase activity of Escherichia coli strain H10407, under different physiological and environmental conditions, e.g. induced and uninduced osmotic stress, light, etc., was undertaken. In this study E. coli was employed as a model for faecal coliforms in waste water. beta-Galactosidase activity was induced by isopropyl-beta-D-thiogalactoside (IPTG). Enzyme activity (U cell-1)/cell for sewage bacteria and for induced E. coli was similar, i.e. log U cell-1 = -8.5 whereas uninduced E. coli yielded log U cell-1 = -12.1. Initial enzyme activity was not dependent on phase of growth of the cell (exponential vs stationary phase) or whether marine or fresh water at the time of initial dilution. However, osmotic change resulted in a decrease in culturable cells, even though enzyme activity remained constant. A significant decrease in the number of culturable bacteria, followed by a decrease in beta-galactosidase activity, was observed after exposure of cells to visible light radiation. It is concluded that beta-galactosidase enzyme is retained in viable but non-culturable E. coli. Furthermore, beta-galactosidase appears to offer a useful and rapid (25 min) measure of the viability of faecal coliforms, and therefore, of the water quality of bathing and shellfishing areas.
An Interdisciplinary Approach to Studying Gene–Environment Interactions: From Twin Studies to Gene Identification and Back

There has been a surge of interest in studying gene–environment interaction; however, research in this area faces a number of challenges. Interdisciplinary collaborations are critical at this juncture. This article reviews studies that illustrate how findings across different literatures can be synthesized to characterize how genetic and environmental influences impact developmental pathways. Developmental scientists are poised to make important contributions to studying gene–environment interaction. However, for this potential to be realized developmental–genetic studies must incorporate the most recent advances in genetics, and bridge the current schism that exists between genetic research being conducted in the fields of psychology and genetics.
Molecular sequence data resolves basal divergences within Simuliidae (Diptera)

Basal divergences within Simuliidae are inferred from portions of the large nuclear ribosomal subunit (28S), elongation factor‐one alpha (EF‐1α), dopa decarboxylase (DDC), phosphoenolpyruvate carboxykinase (PEPCK), the small mitochondrial ribosomal subunit (12S) and subunit two of NADH dehydrogenase (ND2). Sequences from 28S and EF‐1α are presented for a thaumaleid, a chironomid and twenty‐five of the thirty‐two currently recognized simuliid genera. For DDC, PEPCK, 12S and ND2 the taxon sampling is less extensive, but includes both aforementioned outgroup taxa, Parasimulium Malloch, Simulium Latreille and genera representing each of the two to three major suprageneric taxa of various authors. Phylogenetic analyses of 28S, EF‐1α, PEPCK and DDC sequences yield strong support for the basal position of Parasimulium (Parasimuliinae) and division of the remaining simuliids (Simuliinae) into monophyletic sister taxa, Prosimuliini and Simuliini. These groupings are entirely concordant with those recovered in the most intensive analysis of morphological data.
Rhexocercosporidium panacis sp. nov., a new anamorphic species causing rusted root of ginseng (Panax quinquefolius)

A new species of the anamorphic genus Rhexocercosporidium is described. Isolates of a Rhex-Rhexocercosporidium sp. were obtained from ginseng (Panax quinquefolius) roots with symptoms of rusted root. These isolates were found to be genetically and morphologically distinct from the only described species in this genus, R. carotae. Sequence data from the ribosomal DNA region spanning the internal transcribed spacers 1 and 2 and from a portion of the β-tubulin gene of the ginseng Rhexocercosporidium were compared to those of R. carotae. Parsimony analyses of sequence data showed that R. carotae and the ginseng isolates belonged to distinct but closely related clades. Conidia of a typical ginseng isolate were significantly shorter and possessed fewer septa than R. carotae but shared rhexolytic secession of conidia with R. carotae. The binomial Rhexocercosporidium panacis is proposed to accommodate isolates of this genus that are associated with the rusted root disease.
Independent circadian regulation of assimilation and stomatal conductance in the ztl-1 mutant of Arabidopsis

Summary • We have developed a low-cost, multicuvette infrared gas analyser system for medium-term measurement of gas exchange in Arabidopsis thaliana plants. The system enables parallel measurement of stomatal conductance and CO2 assimilation, providing direct comparison between genotypes. This allows the molecular genetic tools that are available in Arabidopsis to be combined with the power of whole-plant physiology. • The system was designed specifically for quantification of circadian rhythms of gas exchange, and controls cuvette relative humidity and CO2 concentration under both continuous light and light–dark cycles. Cuvette humidity is controlled by a unique feedback system that prevents humidity oscillations within the cuvettes. • Using this new system we demonstrated that, under continuous light, there was a longer circadian period for both stomatal conductance and CO2 fixation in the zeitlupe (ztl-1) mutant compared to wild type. • Wild-type ZTL expression is therefore required for normal cycles of CO2 fixation and stomatal conductance. Furthermore, we demonstrate that different circadian periods can coexist in a single plant, highlighting the cell autonomous nature of the plant circadian oscillator.
Host Specificity, Dispersion and Persistence Through Drought of Two Arid Zone Mistletoes

In the Whyalla region of South Australia, the loranthaceous mistletoe Amyema quandang (Lindl.) Tiegh. is virtually host-specific to Acacia papyrocarpa Benth. , whereas Lysiana exocarpi (Behr.) Tiegh. (Loranthaceae) frequently parasitises 12 species in seven families, and less commonly infects seven other species. Amyema quandang is contagiously distributed with respect to Acacia papyrocarpa, larger trees supporting higher numbers of mistletoes. Host branch diameter (HBD) is assumed to index the age of individual mistletoes of Amyema quandang since seedlings only establish on thin host branches. The age distribution of A. quandang is skewed towards young plants since almost half the population para- sitises host branches Ͱ4 15 mm in diameter, within the range infected by seedlings. HBD is correlated with canopy size and the number of haustorial branches. The proportion of reproductive mistletoes increases with HBD and hyperparasitic L. exocarpi are confined to older plants of A. quandang with HBD Ͱ5 31 mm. As a result of the severe drought in 1982, 25% of large plants of A. quandang lost one or two main haustorial branches and suffered reductions in canopy volume, but only 4% died; by contrast, 31% of large L. exocarpi died and a further 19% lost most of their foliage. In the A. quandang population as a whole, recruitment balanced mortality (19%) over a 40 month period, but in the L. exocarpi popu- lation recruitment compensated for only half the mortality. None of the xerophytic shrub and tree hosts of either mistletoe died.
Spore dimensions of Puccinia species of cereal hosts as determined by image analysis1

Digital image analysis was used to measure dimensions of spores produced by Puccinia coronata, P. graminis, P. hordei, P. recondita, P. striiformis and P. triticina. Included were teliospores, basidiospores, urediniospores and, except for P. striiformis, pycniospores and aeciospores. Length, width and projection area of spores were measured with NIH Image or Scion software. By using limits on size, spores were automatically selected and measured, except for teliospores, which required manual elimination of the pedicel and separation of images of adhering spores. Length and width were determined as the major and minor axes of the best fitting ellipse for each spore. This procedure gave values for length and width close to results obtained with an ocular micrometer. Projection area was determined as the number of pixels within spore boundaries multiplied by the area represented by each pixel, giving values that are not feasible to obtain accurately with an ocular micrometer. Of the species studied, spores of P. recondita had the largest dimensions, P. triticina had the smallest. The rank of the six species based on increasing width, length or projection area was almost the same, using each spore type except pycniospores. Generally, differences of 5% in a given spore dimension between two species were significant. Differences between species were greater with basidiospores and aeciospores than with other spore types. Teliospores were unique in that length and width were negatively correlated, resulting in less variation in area than in length or width. The results indicate that image analysis is useful for measuring spore dimensions, that projection area of spores is a useful added parameter for characterizing rust species and that dimensions of teliospores, basidiospores, aeciospores and urediniospores each are potentially useful for differentiating species.
Calcium limitation in Daphnia magna

The role of ambient calcium concentrations on survival, moulting, growth and egg produc- tion was assessed in the cladoceran Daphnia magna. A threshold for survival was found in the range 0.1-0.5 mg Ca l-1, even when ionic strength of the medium was kept constant. Accumulated length and length specific dry weight was retarded at low Ca (0.5-1.0 mg Ca l-1) at food concentrations above incipient limiting level. For lower food levels, the effect of Ca on growth was less clear. The effect of low Ca on growth rate was most manifest during the first days after hatching, reflecting the higher Ca demands of the early juveniles. Age-specific egg production was strongly reduced at Ca concentra- tions <10 mg Ca l-1. This was partly an indirect effect of reduced growth rates, but could also be an effect of higher energetic costs associated with Ca uptake in a Ca-poor medium. The high Ca demands in D.magna may not be representative of other Daphnia species. Nevertheless, high specific Ca content seems to be a common property of Daphnia spp. and Ca deficiency could be a major deter- minant of species success and community structure among crustacean zooplankton; it also puts constraints on carbon sequestration in the pelagic food web of softwater lakes.
Frass sampling and baiting indicate European earwig (Forficula auricularia) foraging in orchards

Abstract: Earwigs are significant generalist predators of a range of orchard pests, but quantitative assessment of earwig density and beneficial impact is difficult. A sampling system was designed and tested, based on field placement of polycarbonate tubes in apple trees as scotophase arboreal refugia. Tubes containing artificial diet and provided with a black plastic sleeve had the highest earwig counts. Tubes with diet or the black sleeve alone were less preferred. Presence of distinctive frass was also evident in polycarbonate tubes containing artificial diet, and earwig frass was recorded at a higher frequency than earwig presence, indicating foraging and detection of the tubes at a higher rate than their use as shelters. At the tree level, there was a weak correlation between frass abundance and predation rates on leafroller egg batches placed as baits in the canopy, but not with earwig density measured by corrugated cardboard rolls or diet tubes. Diet tubes have the potential to offer new insights into earwig foraging behaviour in orchards.
Electrophoretically detectable genetic data for fifteen southern African cichlids

Gene products of 40 loci in 15 species of the cichlid genera Chetia, Hemichromis, Oreochromis, Pharynogochromis, Serranochromis and Tilapia were examined by horizontal starch-gel and vertical polyacrylamide-gel electrophoresis. Electrophoretic analysis of the loci, using aqueous extracts of brain, eye, gill, heart, kidney, liver, serum, stomach muscle, testis and white muscle, revealed the products of 40 loci for routine analysis. Genetic variation within species was observed at 18 loci and average heterozygosities ranged between 0.021 and 0.047 which is less than previous estimates based on fewer loci and smaller sample sizes for the same species. Interspecific variation exists and can be used to identify the species studied. Gene expression is similar among all species studied.
Teaching and Learning of Nature of Scientific Knowledge and Scientific Inquiry: Building Capacity through Systematic Research-Based Professional Development

ABSTRACT This study provides an example of a systematic professional development project designed to build capacity for the teaching of nature of science and scientific inquiry, while not sacrificing the learning of more traditional science subject matter. Specifically, this project examined the impact of a 5-year professional development project on K-12 science teachers’ content knowledge and pedagogical knowledge, and their students’ knowledge, related to nature of scientific knowledge (NOSK) and scientific inquiry (SI). For five years a total of 236 science teachers in K-12 participated in the project and over 23,000 students were affected by the project. During each year of professional development teachers engaged in science internships, NOSK and SI activities, model lessons, curriculum development, microteaching presentations, and assessment practices related to NOSK/SI. The pre- and post-test results from the Views of nature of Science, Form D (VNOSK-D) and the Views About Scientific Inquiry (VASI) instruments indicated that teachers and their students significantly improved their understandings of NOSK/SI. In addition, analysis of teachers’ microteaching lessons showed that there was a developmental continuum of teaching NOSK/SI from implicit to didactic to explicit teaching as teachers progressed through the program.
Effect of NPK fertilization on symptom severity of African cassava mosaic virus

Abstract The effects of nitrogen, phosphorus and potassium fertilizers on African cassava mosaic virus (ACMV) disease severity in an improved cassava variety (U/41044) were investigated during 1989 and 1990 cassava growing seasons. There was significant (P = 0.01) positive correlation (r = 0.956) between increasing levels of N and symptom severity. Also significant (P = 0.01) was plant height with increase in N levels. The observed trend for either year was quadratic in manner with a peak at 90 kg/ha. Increase in rates of either P or K did not significantly affect disease severity as well as plant height. Varying the basal dressing rates (60 kg/ha N, 10 kg/ha P and 50 kg/ha K) simultaneously, did not affect ACMV disease severity but positively correlated (P = 0.05) with plant height. The need for balanced N, P, K fertilization of cassava susceptible to ACMV is imperative.
Data Congruence and Phylogeny of the Papaveraceae s.l. Based on Four Data Sets: atpB and rbcL Sequences, trnK Restriction Sites, and Morphological Characters

Phylogenetic analyses of various combinations of atpB and rbcL sequence data, trnK restriction sites, and morphological characters of taxa representing the Papaveraceae s.l. (Pteridophyllaceae, Fumari- aceae subfamilies Fumarioideae and Hypecoideae, Papaveraceae s. str. subfamilies Eschscholzioideae, Chelidonioideae, Papaveroideae, Platystemonoideae) are presented. Several measures of data set incongru- ency indicate considerable congruence between data sets. In order to correctly identify the root of the family, combined atpB and rbcL sequence data for the Papaveraceae s.l. and appropriate outgroups (Asarum, Illicium, Platanus, Euptelea, and representatives of the Ranunculaceae and Berberidaceae) were analyzed. Regardless of the outgroup used, all topologies obtained suggest that Pteridophyllum (Pteridophyllaceae) is sister group to Fumariaceae and Papaveraceae s. str. Data sets of the ingroup with Pteridophyllum used as the outgroup were analyzed separately and together, with results from the combined data sets showing increased bootstrap support. Contrary to recent claims, Papaveraceae s. str. remain monophyletic after the exclusion of Pteridophyl- lum and Fumariaceae. In the Papaveraceae s. str. , Eschscholzioideae are sister group to Papaveroideae (including Platystemonoideae) and Chelidonioideae (including Glaucium/Dicranostigma). The evolution of floral morphology, geographical distribution, and ecology of Papaveraceae s.l. are briefly discussed.