bluuebunny/crossref_metadata_2025_split huggingface dataset:
Fate of 15N‐Nitrate Applied to a Bermudagrass System: Assimilation Profiles in Different Seasons
Authors: Wherley Benjamin G. , Shi Wei , Bowman Daniel C. , Rufty Thomas W. 
Published: October 2009

ABSTRACTPressures to protect water quality and water shortages are leading to increased applications of effluent water on turfgrasses, and there are pressures to disperse effluent throughout the year. These experiments investigated NO3− uptake efficiency by Tifway bermudagrass [Cynodon dactylon (L.) Pers. × C. transvaalensis Burtt Davy] during growth and dormancy cycles, and thus the potential to filter effluent at different times of the year. Turf–soil cores from field plots were placed in controlled environment chambers and fed solutions with 15N‐NO3− Nitrate uptake was, as expected, greatest in summer when plants were growing rapidly. Less than 10% of applied NO3− was recovered from soil after 3 d. The microbial population was elevated, but little 15N was found in soil microbial or organic fractions. The system was inefficient in winter when bermudagrass was dormant; 80 to 90% of the NO3− remained in soil after 16 d. The system was more efficient than expected in spring and fall transition months, with 80 to 90% assimilated within 1 wk. A large portion of applied 15N was held belowground in rhizomes and roots. Competitiveness of the microbial population was greater in transition months than during rapid bermudagrass growth in August when the population itself was larger. Although seasonal differences occurred, bermudagrass roots were consistently more competitive than the microbial population for applied 15N, an observation very different from that with other grass systems.
Evaluation of Remote Sensing to Measure Plant Stress in Creeping Bentgrass (Agrostis stolonifera L.) Fairways
Authors: Johnsen Aaron R. , Horgan Brian P. , Hulke Brent S. , Cline Van 
Published: October 2009

ABSTRACTTurfgrass irrigation strategies must be clearly defined in response to increasing concerns over quality water availability. Water conservation may be achieved with technologies such as remote sensing. The objectives of this research were to (i) correlate reflectance measurements from creeping bentgrass (Agrostis stolonifera L.) under stress with volumetric water content and turf quality measurements, (ii) determine if remote sensing can detect plant stress before visual observation, and (iii) explore the influence of nitrogen fertility on water stress detection. Four experiments were conducted in the 2006 and 2007 growing seasons on 3‐m2 creeping bentgrass plots maintained under fairway conditions at the University of Minnesota agriculture campus. Treatments were irrigation at 20, 40, 60, and 80% of predicted evapotranspiration every 3 d on plots fertilized with 98 or 244 kg N ha−1 yr−1 Reflectance measurements from two remote sensors were more highly correlated (r = 0.73–0.91) than reflectance and turf quality (r = 0.42–0.71) or reflectance and volumetric water content (r = 0.28–0.64). Reflectance measurements detected water stress 0 to 48 h before visual observation across all treatments and experiments. Nitrogen did not influence the ability to detect drought‐stressed turfgrass. Use of remote sensors to monitor and detect drought stress has the potential to improve turfgrass irrigation and ultimately conserve water.
Quantitative Trait Loci and Epistasis for Oat Winter‐Hardiness Component Traits
Authors: Wooten D. R. , Livingston D. P. , Lyerly H. J. , Holland J. B. , Jellen E. N. , Marshall D. S. , Murphy J. P. 
Published: October 2009

ABSTRACTWinter hardiness is a complex trait and poor winter hardiness limits commercial production of winter oat (Avena spp.). The objective of this study was to identify quantitative trait loci (QTL) for five winter‐hardiness component traits in a recombinant inbred line population derived from a cross between the winter‐tender cultivar Fulghum and the winter‐hardy cultivar Norline. Crown freezing tolerance, vernalization response, and photoperiod response were evaluated in controlled environment studies. Heading date and plant height were evaluated over two seasons in Kinston, NC, and winter field survival was evaluated in five environments over two seasons in the mountains of North Carolina and Virginia. A partial genetic linkage map of regions believed to affect winter hardiness was developed using restriction fragment length polymorphism and simple sequence repeat markers. Most QTL were located on linkage groups FN3, FN22, and FN24. Quantitative trait loci were identified for all traits except photoperiod response, and epistatic interactions were identified for winter field survival, crown freezing tolerance, vernalization response, and plant height. Major QTL for winter field survival (R 2 = 35%) and crown freezing tolerance (R 2 = 53%) were identified on linkage group FN3, which was associated with an intergenomic reciprocal translocation between chromosomes 7C and 17.
Barley Germplasm STARS‐9577B Lacks a Russian Wheat Aphid Resistance Allele at a Quantitative Trait Locus Present in STARS‐9301B
Authors: Mittal Shipra , Dahleen Lynn S. , Mornhinweg Dolores 
Published: October 2009

ABSTRACTRussian wheat aphid (RWA; Diuraphis noxia Kurdjumov) infestations of barley (Hordeum vulgare L.) have reduced yield and quality in the United States since 1986. Resistant germplasm lines, including STARS‐9577B, have been used for cultivar development. Our objective was to map quantitative trait loci (QTL) for RWA resistance in STARS‐9577B and compare them to previously mapped loci. A set of 185 F2:3 families from ‘Morex’/STARS‐9577B was tested in replicated trials in the greenhouse based on a 1 to 9 visual rating of chlorosis. Morex is a susceptible six‐rowed malting barley. Polymerase chain reaction–based markers polymorphic between STARS‐9577B and Morex were used to create a 146 marker linkage map. Quantitative trait loci analysis located two loci for resistance, one on the short arm of chromosome 1H and the other on the long arm of 3H. The 1H locus was associated with a B‐hordein marker, showed additive gene action, and explained 19% of the variation. The 3H locus was associated with marker EBmac0541, showed partial dominance and explained 47% of the variation. Combined, the two loci explain 55% of the phenotypic variation for RWA reaction. Results showed that STARS‐9577B lacks a resistance allele at one of the QTL found in STARS‐9301B, which may explain the consistently higher RWA score (lower resistance) of 3 in STARS‐9577B versus the lower score (higher resistance) of 2 in STARS‐9301B, indicating that the QTL on chromosome 2H is an important factor in determining resistance.
Allelic Variants at the Psy‐A1 and Psy‐B1 Loci in Durum Wheat and Their Associations with Grain Yellowness
Authors: He Xinyao , Wang Jianwu , Ammar Karim , Peña Roberto Javier , Xia Xianchun , He Zhonghu 
Published: October 2009

ABSTRACTPhytoene synthase (PSY) genes are involved in the biosynthesis of carotenoid pigments in durum wheat [Triticum turgidum L. subsp durum (Desf.) Husn.], significantly influencing grain yellowness. This study was conducted to identify new allelic variants at the Psy‐A1 and Psy‐B1 loci in durum wheat, and to evaluate the applicability of functional markers developed from common wheat (Triticum aestivum L.) for durum wheat breeding. Two new allelic variants, Psy‐A1d and Psy‐A1e, were identified at the Psy‐A1 locus, and both the codominant markers YP7A and YP7A‐2 can be used to discriminate the two haplotypes, yielding 194‐ and 231‐bp polymerase chain reaction (PCR) products with YP7A and 1001‐ and 1684‐bp fragments with YP7A‐2, respectively. At the Psy‐B1 locus, three allelic variants were identified. Psy‐B1e was also found in common wheat, whereas Psy‐B1f and Psy‐B1g were detected only in durum wheat. The codominant marker YP7B‐1 can be used to distinguish Psy‐B1f and Psy‐B1g, generating 151‐ and 153‐bp PCR fragments, respectively, and the dominant marker YP7B‐4 was specific to haplotype Psy‐B1e, producing a 717‐bp PCR product. In a set of 100 CIMMYT durum wheat lines with widely variable grain yellowness, the frequencies of Psy‐A1d, Psy‐A1e, Psy‐B1e, Psy‐B1f, and Psy‐B1g were 99, 1, 0, 67, and 33%, respectively, and the genotype Psy‐B1f showed a significant association with higher grain yellowness, whereas the presence of Psy‐B1g led to lower yellowness. A phylogenetic tree generated from the gene sequences of the allelic variants at Psy‐A1 and Psy‐B1 loci indicated two parallel lineages of durum–common wheat, suggesting that more than one tetraploid T. turgidum L. subsp. dicoccon (Schrank) Thell. genotypes were involved in the origin of common wheat. Our results suggested that Psy‐B1f should be paid more attention in durum breeding programs for its association with elevated grain yellowness.
Pollinator Effects on Genotypically Distinct Soybean Cytoplasmic Male Sterile Lines
Authors: Zhao Limei , Sun Huan , Peng Bao , Li Jianping , Wang Shuming , Li Maohai , Zhang Weilong , Zhang Jingyong , Wang Yueqiang 
Published: October 2009

ABSTRACTPoor seed‐set limits potential for soybean hybrid seed production. The objective of this study was to evaluate effects of different pollinators on the rate of seed set in three soybean cytoplasmic male sterile (CMS) lines, JLCMS9A, JLCMS82A, and JLCMS89A. The following five treatments were applied under net room isolation‐conditions: (i) insecticide application and release of alfalfa leafcutter bees (Megachile rotundata) during flowering; (ii) insecticide application in the absence of leafcutter bees; (iii) release of alfalfa leafcutter bees during flowering without insecticide application; (iv) the absence of insecticide or alfalfa leafcutter bees during flowering; (v) plants without a net cover and pesticide application. Results indicated that the rate of pod production and seed set differ significantly between CMS lines and between treatments. Alfalfa leafcutter bees were an effective pollinator as evidenced by increases in pod‐bearing rate and seed‐set rate respectively from 21.35 to 53.22% and from 19.91 to 58.77% in the three CMS lines. The three CMS lines also showed significant differences in seed set, with JLCMS82A exhibiting the highest rate in all five treatments, followed by JLCMS9A and then JLCMS89A. These results suggested that thrips (Sericothrips variabilis) might have some effect on soybean pollination, but did not elicit a major influence based on the low increases in seed production. The natural insect population served an important role in outcrossing and seed set in soybean.
Consequences of ex situ Conservation on the Genetic Integrity of Germplasm Held at Different Gene Banks: A Case Study of Bread Wheat Collected in Pakistan
Authors: Hirano Ryoko , Jatoi Shakeel Ahmad , Kawase Makoto , Kikuchi Akira , Watanabe Kazuo N. 
Published: October 2009

ABSTRACTGenetic diversity and genetic integrity were tested for wheat (Triticum aestivum L.) landraces conserved in two gene banks with considerably different germplasm management systems. We identified two sets of 17 wheat accessions derived from identical sources collected in Pakistan, which were later deposited at the National Institute of Agrobiological Sciences, Japan (NIAS) and the Plant Genetic Resources Program, Pakistan (PGRP). Regeneration of the conserved germplasm was infrequent at both gene banks. Amplified fragment length polymorphism (AFLP) profiles did not indicate prominent changes in the banding patterns of the wheat landraces conserved at the two gene banks. No significant differences were observed in allele frequency of the detected loci in comparison to the original collections (materials preserved without regeneration and multiplication), except in one accession at NIAS. We conclude that genetic diversity was conserved at these two gene banks with different management systems. However, among the 161 scored loci, 26 AFLP bands disappeared at the same loci in NIAS and PGRP accessions, four disappeared only in NIAS accessions, and 28 only in PGRP accessions. At one particular locus, the band disappeared in 12 PGRP accessions but not in NIAS accessions. The results indicate that unique selection might occur at PGRP and that regeneration strategies to reduce it will be needed in the future.
Impact of Genetic Divergence on the Ratio of Variance Due to Specific vs. General Combining Ability in Winter Triticale
Authors: Fischer S. , Möhring J. , Maurer H.P. , Piepho H.‐P. , Thiemt E.‐M. , Schön C.C. , Melchinger A.E. , Reif J.C. 
Published: October 2009

ABSTRACTThe objective of our study was to examine the influence of genetic divergence on the ratio of the components of variance for specific (σ2SCA) and general (σ2GCA) combining ability using experimental data in triticale (×Triticosecale Wittm.). In total, 21 lines and their 210 crosses were evaluated for grain yield in field trials. Published molecular data were reanalyzed, indicating an optimum of two subgroups. The estimates of σ2SCA and σ2GCA were determined for the total diallel and between the two subgroups. The ratio of σ2SCA vs. σ2GCA tended to be lower for crosses between than within genetically distinct groups. Our experimental findings can be interpreted as an indicator of a more favorable ratio of σ2SCA vs. σ2GCA in situations with two genetically distinct populations than in situations with populations that are not genetically distinct.
Selection for Drought Tolerance in Dry Bean Derived from the Mesoamerican Gene Pool in Western Nebraska
Authors: Urrea Carlos A. , Yonts C. Dean , Lyon Drew J. , Koehler Ann E. 
Published: October 2009

ABSTRACTDry bean (Phaseolus vulgaris L.) is highly susceptible to drought stress, and drought affects 60% of global bean production. We evaluated elite exotic dry bean germplasm derived from the Mesoamerican gene pool for drought tolerance, yield, and adaptation to western Nebraska during 2006 and 2007 at three research sites. Seven tropical lines were evaluated with two great northern cultivars (Matterhorn and Beryl‐R) and one pinto cultivar (Bill‐Z) serving as checks. Adjacent nonstressed (NS) and drought‐stressed (DS) blocks were evaluated. Within each block, the selected lines were assigned to experimental units using a randomized complete block design with four replications at each location. On average, yield was 60% less, 100‐seed weight was 19.2% lower, and maturity occurred 4 d earlier under DS than under NS conditions. Beryl‐R, SER 22, and Matterhorn had the greatest average yield under both NS (3564, 3347, and 3440 kg ha−1, respectively) and DS (1701, 1773, and 1584 kg ha−1, respectively). These genotypes were also the most drought tolerant based on the drought susceptibility index (0.9, 0.8, and 0.9, respectively) and geometric mean (2462, 2436, and 2335, respectively). Based on these results, Matterhorn, Beryl‐R, and SER 22 show the most promise for use in breeding for drought tolerance.
Genetic Variation for Resistance to Ear Rots and Mycotoxins Contamination in Early European Maize Inbred Lines
Authors: Bolduan C. , Miedaner T. , Schipprack W. , Dhillon B. S. , Melchinger A. E. 
Published: October 2009

ABSTRACTEar rots caused by Fusarium spp. are a major concern in many maize (Zea mays L.)–growing regions of the world. Our objectives were (i) to evaluate a set of European maize inbreds for resistance to ear rots and mycotoxin concentrations, (ii) to estimate variance components and heritabilities, and (iii) to compute correlations among resistance traits. Forty‐two inbreds were evaluated for resistance to F. graminearum in four environments, and 21 inbreds were evaluated for resistance to F. verticillioides in three environments, under artificial inoculation. Data were recorded on severity of Gibberella (AGER) and Fusarium ear rots and accumulation of deoxynivalenol (DON), zearalenone, and fumonisins. Artificial inoculation was effective particularly for Gibberella ear rot. Genotypic and genotype × environment interaction variances were generally significant. Heritability estimates were moderate to high. Disease severity had strong correlations with respective mycotoxin concentrations. Selection for resistance is expected to have favorable correlated response for mycotoxins particularly with respect to AGER and DON (r p = 0.94). We recommend conducting initial selection on the basis of visual ratings and evaluate the selected elite material for mycotoxin concentrations.
Generalizing the Sites Regression Model to Three‐Way Interaction Including Multi‐Attributes
Authors: Varela Mario , Crossa Jose , Joshi Arun Kumar , Cornelius Paul L. , Manes Yann 
Published: October 2009

ABSTRACTWhen a multienvironment trial (MET) is established across several locations and years, the interaction is referred to as athree‐way arrayThree‐way interaction can be studied by means of three‐way principal components analysis. In this study, the three‐way principal components analysis is adapted to the sites regression model (three‐way SREG). The three‐way SREG with location and year combines the effects of genotype, genotype × location, genotype × year, and genotype × location × year. The objective of this study is to show how the three‐way SREG can be put to practical use in agriculture and breeding. We utilized two wheat (Triticum aestivumL) data sets that have already been used for fitting a three‐way additive main effects and multiplicative interaction model. One data set had genotype (25) × location (4) × sowing times (4) and eight attributes, and the other data set included genotype (20) × irrigation level × year on grain yield. The three‐way SREG applied simultaneously to eight attributes facilitates the interpretation of genotypic performance for all traits in specific locations and across locations for a selected sowing time. Results of the three‐way SREG for both data sets show the different response patterns of genotypes for locations and sowing dates (Data Set 1), as well as genotypic responses across irrigation levels in different years (Data Set 2). Using Data Set 1, we show that fitting a three‐way data structure to a three‐way SREG model is more effective for detecting important interaction patterns than using the two‐way SREG.
Heritability Estimates for Turfgrass Performance and Stress Response in Zoysia spp.
Authors: Schwartz Brian M. , Kenworthy Kevin E. , Engelke M. C. , Genovesi A. Dennis , Quesenberry Kenneth H. 
Published: October 2009

ABSTRACTZoysiagrasses (Zoysia spp.) are widely adapted and highly variable; however, information is lacking regarding the heritability and potential for improvement of numerous performance characteristics. Three individual replicated field studies, which included 90 very fine, 108 fine, and 126 coarse‐textured zoysiagrass genotypes, respectively, were conducted near Gainesville, FL, to determine the response and broad‐sense heritabilities of 10 turfgrass performance and stress‐related characteristics. Genotypic variance largely contributed to the wide range in expressed phenotypic response for plot coverage, turf density, turf quality, genetic color, and seedhead density, which resulted in higher broad‐sense heritability estimates (0.62 ≤ H 2 ≤ 0.94). Fall dormancy and spring greenup were influenced more by the environment and had lower heritabilities (0.32 ≤ H 2 ≤ 0.58). Turf quality was also rated considering the effects of glufosinate [2‐amino‐4‐(hydroxymethylphosphinyl)butanoic acid] herbicide application, Bipolaris incidence, and mole cricket (Scapteriscus spp.) damage. Large error variances and low broad‐sense heritablities were typical for these stress‐related traits. Potential exists for improvement of characteristics that exhibited large amounts of genetic variation and were less influenced by the environment. Broad‐sense heritability estimates indicate the possibility of combining desirable traits in superior clonally propagated F1 hybrids.
Growth Analysis of Biomass Production in Sole‐Crop and Double‐Crop Corn Systems
Authors: Heggenstaller Andrew H. , Liebman Matt , Anex Robert P. 
Published: October 2009

ABSTRACTIncreased biomass productivity could be achieved through double‐cropping if extended growth duration could be realized with minimal reductions in growth efficiency relative to sole‐cropping. To test this hypothesis, functional growth analysis was used to assess the relative importance of photosynthetic duration and efficiency in determining biomass production by sole‐crop corn (Zea mays L.; SC) and double‐crop triticale (×Triticosecale Wittmack)–double‐crop corn (DT–DC). Aboveground dry matter and leaf area were measured weekly, and net dry matter production was assessed for each crop at harvest. Over 2 yr, average harvested dry matter was 25% greater for DT–DC (22.7 Mg ha−1) than for SC (18.2 Mg ha−1), despite greater maximum leaf area index and greater maximum crop growth rate for SC relative to DT–DC. Leaf area duration was increased by 23% for DT–DC compared with SC, while maximum net assimilation rate and seasonal net assimilation rate did not differ between cropping systems. Across systems, variation in yield was positively related to maximum crop growth rate, maximum leaf area index, and leaf area duration but was not associated with maximum or seasonal net‐assimilation rate. Therefore, leaf duration was more important than leaf efficiency in determining productivity in both cropping systems, and greater biomass yield for DT–DC was the outcome of photosynthesis occurring over an extended duration. These results suggest that potential exists to increase biomass productivity by expanding the seasonal interval of photosynthesis, and that in the case of double‐cropping, expansion of leaf duration is not necessarily associated with reductions in leaf efficiency.
Japanese Sake‐Brewing Rice Cultivars Show High Levels of Globulin‐like Protein and a Chloroplast Stromal HSP70
Authors: Kamara Joseph S. , Hoshino Miki , Satoh Yuki , Nayar Nasrin , Takaoka Motoko , Sasanuma Tsuneo , Abe Toshinori 
Published: October 2009

ABSTRACTWhite‐core is an important trait in the selection of rice (Oryza sativa L. ssp. japonica) for sake (Japanese rice wine) production. The present study was conducted to find differences between the endosperm protein pattern of white‐core–bearing sake‐brewing cultivars and those of normal rice grains. Protein patterns of white‐core sake‐brewing grains were compared with those of normal cultivars by two‐dimensional polyacrylamide gel electrophoresis (2D‐PAGE). Several proteins showing different amounts were detected. These were identified by microsequencing and found to be known carbohydrate‐metabolizing enzymes as well as proteins with no known involvement in carbohydrate metabolism. Two units of globulin‐like protein (GLP) and a chloroplast stromal heat shock protein 70 (ctHSP70) showed the greatest difference in the white‐core group. Analysis of amyloplast proteins showed slightly higher amounts of GLP and ctHSP70 in the amyloplast than in the cytosol. Also, time‐course analysis of developing rice grains indicated that both proteins were elevated during the later stages of grain development. From this we conclude that GLP and ctHSP70‐II are associated with white‐core appearance and thus behave as biochemical markers for this character in sake‐brewing rice cultivars.