bluuebunny/crossref_metadata_2025_split huggingface dataset:
On the last mosasaurs: Late Maastrichtian mosasaurs and the Cretaceous-Paleogene boundary in New Jersey
Authors: Gallagher William B. , Miller Kenneth G. , Sherrell Robert M. , Browning James V. , Field M. Paul , Olsson Richard K. , Sugarman Peter J. , Tuorto Steven , Wahyudi Hendra 
Published: April 2012

AbstractNew data regarding the placement of the Cretaceous-Paleogene (K/Pg) boundary in New Jersey is presented based on a recent campaign of drill coring boundary sections in the Atlantic coastal plain of southern New Jersey. The occurrence of late Maastrichtian mosasaurs worldwide and in New Jersey is reviewed in light of the continuing controversy over the rate and cause of the extinction at the K/Pg boundary. At the Meirs Farm site in Monmouth County, NJ, the biostratigraphic position of mosasaur specimens (Halisaurus platyspondylus, Mosasaurus hoffmann) is related to the occurrence of an iridium excursion of 0.5 ppb (5x background levels) in the basal Hornerstown Formation just above the upper Maastrichtian New Egypt Formation. Other specimens in museum collections obtained during the acme of nineteenth century marl mining are from this area of the Maastrichtian outcrop belt in New Jersey. It is concluded that late Maastrichtian mosasaurs show no diminution of their biogeographic ranges and are not particularly rare in New Jersey in comparison to older mosasaur faunas. Mosasaurs became extinct in association with the collapse of the marine food web at the K/Pg boundary, and were replaced as apical marine predators in the early Danian by a variety of crocodilians.
Dental microstructure and geochemistry of Mosasaurus hoffmanni (Squamata: Mosasauridae) from the Late Cretaceous of Turkey
Authors: Chinsamy Anusuya , Tunoǧlu Cemal , Thomas Daniel B. 
Published: April 2012

Abstract
Mosasaurus hoffmanni from Devrekani, Turkey is among the geologically youngest of the ancient aquatic predators. In addition, M. hoffmanni is the only Mesozoic vertebrate reported from Turkey, and has proven useful in the understanding of paleogeographic segregation within Mosasauridae. Here we provide an analysis of the histology and geochemistry of a functional maxillary tooth of this Turkish mosasaur. Dental histology included descriptions of lines of von Ebner and contour lines of Owen in dentine, as well as microstructural details pertaining to the enamel structure. Considering the spacing of the lines of von Ebner, the odontoblast deposition of the dentine (at the level of sectioning of the crown) was estimated to have taken approximately 511 days. A replacement tooth was fortuitously discovered upon sectioning the functional tooth, and given the thickness of the dentine visible, it is estimated that it took 233 days to deposit the centripetal layer of dentine. Energy dispersive spectroscopy, x-ray diffractometry, fusion disc x-ray fluorescence and Sr isotope measurements suggested that the tooth had undergone heterogeneous diagenetic alteration. Despite signs of alteration, the anatomy and chemistry of the M. hoffmanni teeth provided significant paleobiological and paleo-environmental insight.
Campanian and Maastrichtian mosasaurs from Antarctic Peninsula and Patagonia, Argentina
Authors: Fernández Marta S. , Gasparini Zulma 
Published: April 2012

Abstract
Mosasaurs from Antarctica have been recovered from the late Campanian and early and late Maastrichtian in James Ross, Vega and Seymour Islands within the James Ross basin. Tylosaurinae are represented by the late Campanian-early Maastrichtian remains of Taniwhasaurus antarcticus [Novas et al., 2002] and by late Maastrichtian Tylosaurinae indet.; Plioplatecarpinae by late Maastrichtian Plioplatecarpus sp.; and Mosasaurinae by late Maastrichtian “Liodon” sp., Mosasaurus sp. and Mosasaurinae indet. Materials from Cape Lamb, recently identified in the Museo de La Plata collection (Argentina), suggest that the stratigraphic range of Plioplatecarpus and “Liodon” within the James Ross basin extends back to the early Maastrichtian. At present, the holotype of T. antarcticus is the most complete specimen exhumed from Antarctica. In northern Patagonia, mosasaurs have been recovered from the late Maastrichtian of the Jagüel Formation, Neuquén basin. Patagonian mosasaurs are represented by Mosasaurus sp. aff. M. hoffmanni, Plioplatecarpus sp., Prognathodon sp., and Mosasaurinae indet. Presently, no Tylosaurinae have been found in Patagonia. Both in the James Ross and Neuquén basins, Mosasaurus sp. and Plioplatecarpus sp. occurred close to the K/Pg. boundary.
Evolution of the African Rice: A Historical and Biological Perspective
Authors: Nayar N. M. 
Published: April 2012

ABSTRACTThe usual assumption is that African rice (Oryza glaberrimaSteud.) originated about 3500 yr ago from the annual wild rice,Oryza barthiiA. Chev., and Asian rice (Oryza sativaL.) was introduced into West Africa in the late 15th century CE) by the Europeans. Evidences from several social science and biological science disciplines have been collated and/or reinterpreted to draw the following inferences: (i) There are several accounts of rice culture in northern and western Africa from early centuries of the Common Era; (ii) The Senegambian monoliths, linked to the time of origin of African rice as 3500 yr ago, have been carbon dated to the 7th century CE; (iii) Neolithic culture had hardly reached tropical West Africa 3500 yr ago; (iv) The characteristics ofO. barthiivis‐à‐vis the two cultivated rices—bigger grains, higher yields, easy crossability with both intermediate features, and weediness—may suggest its hybrid nature; and (v) The rarity ofO. glaberrimabeginning with the time of its initial identification, acceptance of local farmers to having both rices growing together, repeated discovery ofO. glaberrima–like forms in non‐African rice regions, and prevalence of close colinearity between the two cultivated rices at molecular and chromosomal levels suggest their close relationships. These factors indicate that African rice might have evolved from Asian rice, and that the wild rice,O. barthii, might be a hybrid derivative of the two cultivated rices.
Genome Selection Sweep and Association Analysis Shed Light on Future Breeding by Design in Wheat
Authors: Ge Hongmei , You Guangxia , Wang Lanfen , Hao Chenyang , Dong Yushen , Li Zhensheng , Zhang Xueyong 
Published: April 2012

ABSTRACTTwo sets of bread wheat (Triticum aestivum L.) varieties and their respective founder parents (St2422/464 and Abbondanza) in China were genotyped at 481 microsatellite loci. The selection sweeps detected almost completely overlapped with one another across the two sets on the 21 chromosomes although a cluster analysis showed that they do represent distinct subpopulations with Fst = 0.0734 (minor allele frequency [MAF] = 0.1, –log10p = 5). About 38.7% of the loci appeared to have experienced some selection sweep. Important agronomic traits were usually associated with these selection sweep valleys. The alleles present at key loci in these valleys were often in common between the two founders. Marker–trait association based on three seasons of field data suggested the association of one, four, and six loci with, respectively, the number of fertile tillers per plant, grain number per spike, and thousand grain weight. Five, 14, and 21 loci were associated with the three yield components in two of the three seasons. We suggest that the breeding potential of a line can be predicted from its allelic state at certain critical marker loci, which represent major targets for breeding by design in wheat. Genotypic descriptions of major cultivars and the analytical approach we have described here provide a path toward the a priori selection of favorable breeding parents.
Identification of Cold‐Tolerant Breeding Lines by Quantitative Trait Loci Associated with Cold Tolerance in Rice
Authors: Jena K. K. , Kim S. M. , Suh J.P. , Yang C. I. , Kim Y.G. 
Published: April 2012

ABSTRACTLow temperature or cold stress is one of the major abiotic stresses limiting rice (Oryza sativa L.) production and productivity in the temperate rice growing regions as well as in tropical high lands worldwide. Low temperature at the reproductive stage causes high sterility and decreases production. In this study, we assessed recombinant inbred lines (RILs) that possessed cold‐tolerance genes and/or quantitative trait loci (QTL) from the donor line IR66160‐121‐4‐4‐2 in the genetic background of a cold‐sensitive japonica cultivar, Geumobyeo. The selected 15 RILs with QTL for cold tolerance were phenotyped for three main agronomic traits—culm length (CL), days to heading (DTH), and spikelet fertility (SF)—which were most affected during cold stress. The RILs with cold‐tolerant and cold‐sensitive parents were evaluated under cold‐water (18–19°C) irrigation in the field and cold‐air temperature (17–18°C) in the temperature‐controlled greenhouse. The RILs showed significant differences in these traits compared to the cold‐sensitive parent. Traits CL and DTH exhibited positive correlation with SF in the selected breeding lines. The SF of the selected breeding lines was higher (51–81%) than that of the cold‐sensitive parent, Geumobyeo (7%). Our results confirmed that cold tolerance was associated with SF but the traits CL and DTH were differently associated with cold tolerance. The cold‐tolerant breeding lines selected in this study had at least one of the three QTL associated with cold tolerance. The breeding lines confirmed to have cold tolerance are useful to breed cold‐tolerant cultivars and increase our understanding of the mechanism of cold tolerance in rice.
Tiller Characteristics of Timothy and Tall Fescue in Relation to Herbage Mass Accumulation
Authors: Virkajärvi Perttu , Pakarinen Kirsi , Hyrkäs Maarit , Seppänen Mervi , Bélanger Gilles 
Published: April 2012

ABSTRACTHerbage dry matter (DM) yield of grasses is a function of the density and size of vegetative (VEG), generative (GEN), and elongating vegetative (ELONG) tillers. We determined the contribution of these three tiller types to DM yield accumulation along with their main morphological characteristics on three sampling dates during each of the primary growth and the regrowth of field‐grown swards of timothy (Phleum pratense L.) and tall fescue (Festuca arundinacea Schreb.). Our results provide the first quantitative characterization of ELONG tillers, which contributed to timothy DM yield by up to 28% in primary growth and 58% in regrowth. In tall fescue, VEG tillers were dominant in primary growth and regrowth (74 to 100% of DM yield). The GEN tillers were dominant (67 to 74% of DM yield) in the primary growth of timothy while in the regrowth, VEG tillers were dominant early (84% of DM yield) but ELONG tillers represented 58% of DM yield later on. Timothy and tall fescue had similar rates of DM accumulation. The greater DM yield on all sampling times of the regrowth of tall fescue confirms a greater growth before the first sampling, most likely due to the greater proportion of VEG tillers. The GEN tillers were large with low leaf to weight ratio (LWR) and proportion of attached senesced material whereas VEG tillers were small with high LWR and large proportion of attached senesced material. The ELONG tillers were intermediate in size and LWR but they had a low proportion of attached senesced material.
The Maize Leaf Starch Mutation agps‐m1 Has Diminished Field Growth and Productivity
Authors: Schlosser Alanna J. , Martin John M. , Hannah L. Curtis , Giroux Michael J. 
Published: April 2012

ABSTRACTModification of enzymes involved in sink or source strength has been one common method used in attempts to improve cereal yield. In this regard, ADP‐glucose pyrophosphorylase (AGPase) has received considerable attention because it controls the rate‐limiting step in starch biosynthesis in both leaves and seeds. Previous studies, focused on increasing AGPase activity in seeds, indicate that productivity increases occur only when environmental resources are nonlimiting. The objective of this study was to determine the importance of leaf starch on the productivity and growth of maize. Field trials of BC4F2:3 plants segregating for the agps‐m1 mutation and leaf starch were conducted. The results clearly demonstrate the importance of normal leaf starch levels to maize productivity. The starchless agps‐m1 plants were 6 to 15 cm shorter, flowered 2 to 6 d later, and were 30% lower yielding than their wild‐type sister lines. Photosynthetic rates were not significantly different between wild‐type and agps‐m1 plants. However, agps‐m1 leaves were significantly lower in the levels of major photosynthetic proteins such as phosphoenolpyruvate carboxylase, pyruvate phosphate dikinase, and RuBisCO until the end of the photoperiod. The results demonstrate a link between leaf starch and whole plant productivity under agronomic conditions. Further study would help to define how leaf starch regulates the production of leaf photosynthetic proteins.
Variation for Canopy Morphology in Little Bluestem
Authors: Springer T. L. 
Published: April 2012

ABSTRACTLittle bluestem, Schizachyrium scoparium (Michx.) Nash, is a native grass that has been shown to have high levels of genetic variation for traits such as biomass yield, disease resistance, plant height, leafiness, maturity, and seed yield. If high levels of genetic variation exist for these traits, it is likely that it would exist for other traits as well. Thus, the objectives were to describe the variation in traits that contribute to canopy morphology within and among little bluestem parental lines, an F1 plant population, and selected F1 populations. Plants were classified as not upright (NU), upright compact (UC), or upright open (UO) on the basis of their shape. As expected, all parental lines expressed considerable variation for frequencies of discrete morphological traits and for continuous morphological traits. The F1 plant population was characterized by 12.2% NU plants, 22.4% UC plants, and 65.4% UO plants. The selected populations were fixed for several discrete variables, including growth form, lack of lodging, and little or no leaf rust. To fully exploit the genetic variability of little bluestem, it would be necessary to obtain ecotypes from throughout its natural range and breed and select for new genetic variation that could be captured through recurrent selection. Little bluestem is an ideal species for breeding new cultivars and/or germplasm lines for pasture and rangeland renovation, roadside revegetation, wildlife habitat, and recreation areas.
Influence of Growing and Storage Conditions on Bakery Quality of Traditional Maize Varieties under Organic Agriculture
Authors: Revilla Pedro , Landa Arsenio , Rodríguez Almudena , Ordás Amando , Malvar Rosa Ana 
Published: April 2012

ABSTRACTMaize (Zea mays L.) used for human consumption is frequently processed following traditional methods with unknown effects. The objectives of this research consist of studying genotypic and environmental effects on grain quality for human consumption and evaluating traditional grain processing methods. Three maize varieties were evaluated for 2 yr in two locations. Populations were significantly different for grain quality while grain yield and pericarp damage were mostly affected by environment. Moisture content varied from 24% for early harvest to 20% for late harvest, pericarp damage from 24 to 19%, and germination from 62 to 84%. Environments explained most of the variation while harvest dates affected mainly grain hardness and germination. In addition, white flint maize grains were processed with a combination of drying, freezing, vacuum, and storage treatments. Drying with warm air after natural drying increased grain quality compared to natural drying alone. Medium term storage increased grain quality but reduced germination. Traditional processing was adequate for adapted varieties and typical uses but additional drying, freezing, or vacuum can be worthwhile depending on grain conditions and final use. To optimize quality, the key issues are appropriate growth cycle and proper harvest time. Furthermore, quality and agronomic performance can be managed independently of each other except for the negative correlation between moisture and milling test.
Cytohistological Analysis and Mobilization of Reserves in Jatropha curcas L. Seed
Authors: Reale Lara , Ricci Anna , Ferranti Francesco , Torricelli Renzo , Venanzoni Roberto , Falcinelli Mario 
Published: April 2012

ABSTRACTJatropha curcas L. is gaining interest as a promising energy crop whose oil is suitable for biodiesel production. The aim of our investigation was to study the type, localization, and dynamics of the reserves in J. curcas seed, which is considered the principal product of this species, utilized for biodiesel production. We investigated the cyto‐anatomical structure of the mature and germinating seeds and the storage substances localization in their different tissues. To this aim different techniques of light and electron microscopy were utilized (toluidine blue and periodic acid‐Schiff [PAS] staining and transmission electron microscope [TEM] observations). The results showed that, in mature seeds, protein vacuoles and oil bodies were present in the endosperm, embryo, and cotyledons. During germination the endosperm reserves were mobilized and the endosperm was characterized by vacuolated cells without protein and oil reserves; the oil and protein content also decreased in the cotyledons where, at this stage, starch grains appeared. Starch grains were also detected in the hypocotyl, where oil and protein reserves were not observed. Our studies confirmed that all portions of the mature seed (except the seed coat) contributed to store reserves and were a good source of oil, while immediately after germination the distribution of reserves was significantly modified and seeds were not a good source of the oil.
Field Evaluation of Rice Genotypes from the Two Cultivated Species (Oryza sativa L. and Oryza glaberrima Steud.) and Their Interspecifics for Tolerance to Drought
Authors: Ndjiondjop Marie Noelle , Futakuchi Koichi , Cisse Fousseyni , Baimey Hugues , Bocco Roland 
Published: April 2012

ABSTRACTA total of 327 rice (Oryza spp.) genotypes were screened for tolerance to drought at the Africa Rice Center in Cotonou, Benin, in 2007 and 2008. Plants were subjected to full irrigation from sowing to harvest or to 21‐d drought from 34 d after sowing. Drought‐affected plants showed narrower leaves, reduced grain yield, and shorter stature. Tillering and plant maturity were negatively affected by drought whereas values for leaf temperature and leaf greenness were significantly higher under drought than under control condition. Under control condition, for 54% of genotypes, flowering occurred between 71 and 90 d after sowing. But under drought, flowering occurred at 90 or more days after sowing for the majority of genotypes. Significant genotype × environment interactions were observed for plant height, leaf greenness, flowering, grain yield, maturity, leaf rolling, and leaf tip burning. More traits were correlated with grain yield under drought for Oryza glaberrima Steud. than for other genotype groups. No relationship was observed between plant recovery ability and all other traits selected. More than 90% of plants evaluated resumed growth after drought in both years. TOG6208, TOG5691, TOG5591, TOG6594, and RAM122 were identified as best performing genotypes in terms of grain yield under drought. Their performance was similar to that of most of the 24 top yielding in terms of leaf rolling, leaf tip burning, and plant recovery after drought release.
Diallel Analysis of Photosynthetic Traits in Maize
Authors: Cai Q. S. , Wang L. L. , Yao W. H. , Zhang Y. D. , Liu L. , Yu L. J. , Fan X. M. 
Published: April 2012

ABSTRACTCapability to intercept and utilize sunlight is important in maize (Zea mays L.) for its growth and dry matter accumulation. Little research has been conducted on the combining ability of maize physiological traits related to photosynthesis, such as light saturation point (LSP), light compensation point (LCP), apparent quantum efficiency (AQE), maximum photosynthesis (Pmax), total protein content (PRO), and activity of phosphoenolpyruvate carboxylase (PEPC) and ribulosebisphosphate carboxylase (RuBPC). The five photosynthesis‐related traits and two key enzymes were examined for their combining abilities using a six‐parent diallel design. The objectives were to (i) evaluate general combining ability (GCA) and maternal (MAT) effects of the six maize lines and specific combining ability (SCA) and nonmaternal (NMAT) effects for crosses and (ii) determine if GCA effects were different among three maize heterotic groups. Results revealed that the additive gene effects were more important than nonadditive effects for LSP, LCP, Pmax, PRO, PEPC, and RuBPC. Maternal effects for LCP, PRO, and RuBPC were significant and positive for some lines, which could be used as female parents in hybrid development. Information on means of parental lines, combining ability, and heterosis values suggested that RUBPC, PEPC, and PRO might be the key traits that make the Suwan 1 heterotic group different from the Reid and non‐Reid groups and should be explored fully in future hybrid maize breeding programs.
Comparison of Phenotypic Methods and Yield Contributions of Quantitative Trait Loci for Partial Resistance to Phytophthora sojae in Soybean
Authors: Wang Hehe , St. Martin Steven K. , Dorrance Anne E. 
Published: April 2012

ABSTRACTIn several host–pathogen systems, the detection of an individual quantitative trait locus (QTL) differed depending on the specific pathogen isolate or phenotypic assay that was used. Moreover, the contribution of a QTL toward yield is an important factor for selecting specific QTL candidates for resistance breeding. The first experiment in this study compared the QTL identified previously in a ‘Conrad’ × ‘Sloan’ F4:6 soybean [Glycine max (L.) Merr.] population challenged with Phytophthora sojae Kaufmann and Gerdemann isolate 1.S.1.1 to the QTL identified when this same population was challenged with isolates PT2004C2.S1 and OH25 using a tray test assay. In the second experiment, QTL were mapped in the same population with P. sojae isolate 1.S.1.1 using a different phenotypic assay, the layer test. In the third experiment, the impact of these QTL on soybean yield was evaluated using 20 selected recombinant inbred lines (RILs) grown in a field infested with P. sojae. Resistance QTL with smaller effects, especially those from the susceptible parent, were not consistently detected with the three isolates or the two phenotypic assays. Composite interval mapping identified a major Conrad QTL on chromosome 18 and one on 19 that were detected with all three isolates and both phenotypic assays. Recombinant inbred lines with resistance alleles at these QTL had significantly higher yields (∼1000 kg ha−1 more) than RILs with susceptible alleles. These results indicate the important role these QTL play in conferring partial resistance to P. sojae.