bluuebunny/crossref_metadata_2025_split huggingface dataset:
Irrigated Hybrid Maize Crop Yield Losses Due to Barley Yellow Dwarf Virus‐PAV Luteovirus
Authors: Beuve M. , Naïbo B. , Foulgocq L. , Lapierre H. 
Published: July 2010

ABSTRACTPAV, one of the luteoviruses inducing the barley yellow dwarf disease, greatly reduces yield of cereal crops and has been reported to cause reddening in several varieties of maize (Zea mays L.). However, there have been no reports that the virus causes significant reductions in size or yield of irrigated maize. Trials to assess the effect of PAV on maize yields were conducted for 3 yr with two hybrids (‘Déa’ and ‘Nobilis’) and two isolates of PAV (2t and L14). These two isolates differed in geographic origin and virulence on barley (Hordeum vulgare L.), but they multiplied similarly to wild isolates in leaves of maize hybrids. The virus was detected in maize leaves during the same period after inoculation in two out of three years. The reason for low levels of virus in leaves in the 1996 season may have been high temperatures (>30°C) following inoculation. Under these conditions, the virus was restricted to the roots for long periods. This blocking of virus migration and/or foliar multiplication was accompanied by less reddening, and there was almost no decrease in grain yield. High early leaf infection of the virus had little effect on the vegetative development of the hybrids (<10% reduction in plant height), but grain yield was between 15 and 20% lower for a production of 10 to 12 t ha−1 This drop in yield was due to fewer kernels of maize per ear, while the 1000 kernel mass was unaffected. The loss in yield was not affected by either the virus isolate or the maize hybrid, although the intensity of symptoms differed between hybrids. The data show that there are potential losses incurred by PAV on maize yield. Therefore, these findings justify the establishment of a breeding program.
Opportunities to Improve Adaptability and Yield in Grasses
Authors: Morgan Page W. , Finlayson Scott A. , Childs Kevin L. , Mullet John E. , Rooney William L. 
Published: July 2010

ABSTRACTPopulation trends predict increasing food needs while progress in developmental and genomic plant sciences offer new opportunities for crop improvements. The grass‐based grain crops have a high degree of synteny in their genomes, thus raising the possibility of using specific information more broadly. Studies of Sorghum bicolor (L.) Moench are beginning to link physiological behavior to specific genes and hormone‐based regulatory systems in ways that suggest specific strategies for improvement. Findings from several other grasses are adding to the pool of information being derived from Sorghum This information relates to flowering and floral development, maturity and senescence, temperature effects via the biological clock, shade avoidance behavior, apical dominance, shoot elongation, and root development including constitutive aerenchyma formation. These studies, along with others, offer a number of options for conventional plant breeding and genetic transformations to improve grass‐based crops and satisfy part of the projected human food needs of coming decades.
Inheritance of Fertility Restoration for Two Cytoplasmic Male Sterility Sources of Helianthus pauciflorus (rigidus) Nutt.
Authors: Jan C. C. , Zhang T. X. , Miller J. F. , Fick G. N. 
Published: July 2010

ABSTRACTNew sources of cytoplasmic male sterility (cms) and fertility restoration genes would reduce the genetic vulnerability of commercial sunflower (Helianthus annuus L.) hybrids because of the current use of a single male sterile H. petiolaris Nutt. cytoplasm and a few fertility restoration genes. The objectives of this study were to evaluate the inheritance of fertility restoration, to compare the cytoplasmic similarity between the two cms sources, and to confirm the vigor reducing effect of combining perennial species cytoplasms with cultivated nuclei. Cms‐RMX plants, maintained by backcrossing with inbred line HA89, were crossed with 21 prospective restoration lines. Male‐fertile F1 progeny were observed in crosses with ‘Luch’ and ‘RCMG1’. Segregation of male sterility in F2 and testcrosses with HA89 indicated fertility restoration was controlled by two complementary dominant genes. Identical segregation ratios of male fertile to male sterile in both F2 and testcross F1 were obtained with cms‐RIG1 using the fertility restoration genes identified for cms‐RIGX. These results suggest a single origin of the two cms sources. In a field test, cms‐RIGX plants produced no seeds after self‐pollination, and 99% seed set from open‐pollination, indicating complete male sterility and female fertility. The new cms‐RIG sources and corresponding fertility restoration genes will provide cytoplasmic diversity for sunflower hybrid production.
Selection for Large Seed and High Protein in Two‐ and Three‐Parent Soybean Populations
Authors: Alt Brian J. , Fehr Walter R. , Welke Grace A. 
Published: July 2010

ABSTRACTSoybean [Glycine max (L.) Merr.] cultivars with large seed size and high protein content are desirable for the production of tofu and other food products. The objectives of this study were to evaluate the amount of genetic variability and the effectiveness of single‐plant selection for seed size and protein in two‐ and three‐parent soybean populations. Two parents with large seed and high protein (LSHP) and one parent with normal seed size and protein (N) were used to produce three population types: LSHP × N, LSHP × LSHP, and LSHP × (LSHP × N). Four sets of the three population types were evaluated with different parents in each set. For each of the populations, 100 random F2 plants and 10 plants of each parent were harvested at Ames, IA, and their seed size and protein were measured. The F3 progeny of the 100 F2 plants and 10 entries of the three parents of each set were evaluated in replicated tests at two Iowa locations. The percentage of F2:3 lines with seed size greater than or equal to the smallest LSHP parent and protein greater than or equal to the lowest LSHP parent in the set averaged 4% for the LSHP × N, 88% for the LSHP × LSHP, and 31% for the three‐parent crosses. Single‐plant selection was not considered cost effective in the LSHP × N populations because the percentage of acceptable segregates was so small or in the LSHP × LSHP populations because the percentage of acceptable segregates was so high. For the three‐parent populations, single‐plant selection was most effective when the F2 plants were ranked for the two traits and those with the most favorable rank were selected for evaluation as F2:3 lines. LSHP × LSHP and three‐parent populations should be the most useful for developing LSHP cultivars.
Fresh Green Seed Yield and Seed Nutritional Traits of Vegetable Soybean Genotypes
Authors: Rao M. S. S. , Bhagsari A. S. , Mohamed A. I. 
Published: July 2010

ABSTRACTEdamame (pronounced eh‐dah‐MAH‐meh) are large‐seeded soybean [Glycine max (L.) Merr.] harvested as green pods at the R6 stage when the seed are approximately 80% matured. The demand for edamame as fresh or frozen vegetable is increasing worldwide. Currently, lack of adapted edamame cultivars is one of the major factors limiting its commercial production in the southeastern USA. A need exists, therefore, to evaluate and identify Asian vegetable soybean genotypes for potential production and/or as a source of vegetable traits for breeding suitable cultivars. In a 4‐yr study, six Japanese edamame cultivars, four large‐seeded Japanese plant introductions, two Chinese vegetable soybean cultivars, and two adapted U.S. cultivars were evaluated for fresh green pod and seed yields and seed composition at the R6 stage. The genotypes were planted in a randomized complete block with four replications and were harvested at the R6 stage. The mean fresh pod and seed yields were 18.5 and 9.6 Mg ha−1, respectively. The PI 181565, ‘Tambagura’, ‘Shangrao Wan Qingsi’, and PI 200506 with fresh pod and seed yields in excess of 20 and 10 Mg ha−1, respectively, offer potential for commercial production in Georgia. The seed oil and protein contents ranged from 130.7 to 155.8 and 333.2 to 386.0 g kg−1, respectively. The mean glucose content was 67.1 g kg−1, whereas the mean phytate content was 12.6 g kg−1 Fresh pod weight was the major yield determinant (R2 = 0.88). The Japanese edamame genotypes may be utilized as a source of vegetable soybean traits in breeding programs.
Agrobacterium‐Mediated Genetic Transformation of Switchgrass
Authors: Somleva M. N. , Tomaszewski Z. , Conger B. V. 
Published: July 2010

ABSTRACTAlthough Agrobacterium tumefaciens has been successfully used to transfer genes to a wide range of plant species, it has received little attention for transformation of forage grasses. Therefore, the objective of the present study was to demonstrate Agrobacterium‐mediated transformation of switchgrass (Panicum virgatum L.). The A. tumefaciens strain AGL 1 carrying the binary vector pDM805, coding for the phosphinothricin acetyltransferase (bar) and β‐glucuronidase (gus) genes, was utilized in these experiments. Somatic embryos, embryogenic calluses, mature caryopses, and plantlet segments served as target tissues for infection. Treated cultures were selected in the presence of 10 mg L−1 bialaphos and the resultant plantlets were treated with the herbicide Basta [monoammonium 2‐amino‐4(hydroxymethylphosphinyl)butanoate]. T‐DNA delivery efficiency was affected by genotype, explant used and the presence or absence of acetosyringone (3′,5′‐dimethoxy‐4′‐hydroxyacetophenone) during inoculation and cocultivation. Approximately 600 transgenic plants were produced, and transformation efficiencies ranged from 0 to nearly 100%. Stable integration, expression, and inheritance of both transgenes were confirmed by molecular and genetic analyses. Approximately 90% of the tested plants appeared to have only one or two copies of the T‐DNA inserts. Controlled crosses between T0 and nontransgenic ‘Alamo’ plants indicated the expected ratio of 1:1 (transgenic:nontransgenic) in T1 plants for both transgenes according to a χ2 test at P = 0.05. These results indicate that the Agrobacterium method is effective for transferring foreign genes into switchgrass.
Quantitative Determination of Phytate and Inorganic Phosphorus for Maize Breeding
Authors: Lorenz Aaron J. , Scott M. Paul , Lamkey Kendall R. 
Published: July 2010

ABSTRACTPhytate is the dominant storage form of phosphorus (P) in mature cereal and oil grains. Phosphorus bound in phytate is nutritionally unavailable to monogastric animals and thus contributes to water pollution because it is excreted in the waste. Also, phytate can chelate certain minerals and exacerbate human mineral deficiencies. Our primary objective was to develop a rapid and inexpensive method of measuring phytate and inorganic P (Pi) concentrations in maize (Zea mays L.). The procedure reported herein was derived from previously published assays and used to screen 50 inbred lines to determine its potential in a selection program. Grain yield, protein, oil, methionine, lysine, tryptophan, and kernel weight were also measured. Field repeatability values for phytate and Pi (0.78 and 0.91, respectively) suggest that our protocol can be used to make heritable measurements on both traits. Phytate measurements taken with the procedure reported herein matched closely those obtained through ion exchange. The combination of adequate precision and simplicity make this method ideal for breeders interested in improving Pi and phytate levels simultaneously. The positive phytate:protein correlation reported commonly was also detected in this study. A relationship between phytate and kernel weight indicates that selection for low phytate may result in larger kernels.
Combining Abilities and Heterosis for Forage Yield among High‐Yielding Accessions of the Alfalfa Core Collection
Authors: Bhandari H. S. , Pierce C. A. , Murray L. W. , Ray I. M. 
Published: July 2010

ABSTRACTCharacterization of genetic parameters in plant germplasm repository populations can facilitate their utilization in commercial breeding programs. This study investigated genetic combining abilities and heterosis for forage yield among diallel hybrids derived from nine previously selected high‐yielding accessions of the USDA‐ARS National Plant Germplasm System core collection of alfalfa (Medicago sativa subsp. sativa L.). These accessions originated from Turkey, South Africa, Greece, Afghanistan, Israel, Uzbekistan, Mexico, Morocco, and the USA. Forage yield response of the parents and their hybrids was determined near Las Cruces, New Mexico. General combining ability (GCA) and specific combining ability (SCA) effects were significant. The magnitudes of the GCA effects were about 5% (<0.71 Mg ha−1) relative to the mean yield of the parents (15.4 Mg ha−1). The Turkey, Afghanistan, and Uzbekistan accessions demonstrated significant positive GCA effects. Accessions from Greece and Morocco demonstrated negative GCA effects. Six hybrids outperformed the average of six commercial cultivars. Five of these six hybrids demonstrated positive SCA effects. Midparent heterosis ranged from –17 to 17%. The results indicate that crossing between alfalfa populations possessing high per se performance and different fall regrowth responses is likely to produce a higher proportion of high‐yielding hybrids in environments experiencing intermittent subfreezing winter conditions.
Reduction of a Triticum monococcum Chromosome Segment Carrying the Softness Genes Pina and Pinb Translocated to Bread Wheat
Authors: Bonafede Marcos , Kong Lingrang , Tranquilli Gabriela , Ohm Herbert , Dubcovsky Jorge 
Published: July 2010

ABSTRACTEndosperm texture, i.e., the hardness or softness of the grain, is an important trait because it determines many end‐use properties of wheat (Triticum aestivum L.). It is primarily controlled by the puroindoline genes (Pina and Pinb) at the Hardness (Ha) locus, mapped on the short arm of chromosome 5D. The introgression of functional Pin genes from diploid wheat Triticum monococcum L. chromosome 5Am into hexaploid wheat resulted in softer grains, suggesting that this translocation might be useful for soft wheat breeders. However, the translocated segment includes a large portion of the 5Am short arm and may carry detrimental genes for agronomic performance. In this study we have generated a backcross (BC) population of 210 individuals where 5A‐5Am homeologous recombination was induced by the ph1b mutation to recover individuals with a reduced translocated segment. A map of this region was constructed using specific sequence tagged site (STS) markers for the three T. monococcum Ha–related genes, the completely linked BGGP gene, three wheat ESTs (BG606847, BF474606, and BQ168958), and two microsatellite markers. Eight plants with recombination events between XBggp and the closest proximal locus BG606847 were identified. Of these, four have the desired T. monococcum allele at the Ha locus. These plants carry a 6.3‐cM segment of T. monococcum chromatin proximal to the Ha locus. This germplasm, which will be publicly available, and the molecular markers developed in this study will be valuable tools for soft wheat breeding programs.
A Large‐Effect QTL for Grain Yield under Reproductive‐Stage Drought Stress in Upland Rice
Authors: Bernier Jérôme , Kumar Arvind , Ramaiah Venuprasad , Spaner Dean , Atlin Gary 
Published: July 2010

ABSTRACTGenetic control of yield under reproductive‐stage drought stress was studied in a population of 436 random F3–derived lines from a cross between the upland rice (Oryza sativa L.) cultivars Vandana and Way Rarem. Screening was conducted under upland conditions at IRRI during the dry seasons of 2005 and 2006. Lines were evaluated in drought stress and nonstress trials in both years to identify QTL contributing to drought resistance. For QTL detection, a set of random lines and the highest and lowest‐yielding lines under both stress and nonstress conditions were genotyped by 126 SSR markers. A QTL (qtl12.1) with a large effect on grain yield under stress was detected on Chromosome 12 in both years. The whole population was genotyped for additional markers on Chromosome 12, allowing QTL localization to a 10.2 cM region between SSR markers RM28048 and RM511. Under stress conditions, the locus also increased harvest index, biomass yield, and plant height while reducing the number of days to flowering. Under nonstress conditions, qtl12.1 did not significantly affect any trait. The additive effect of this QTL on grain yield under stress was 172 kg ha−1 per year over the 2 yr of testing, representing 47% of the average yield under stress and explaining 51% of the genetic variance. The yield‐increasing allele was derived from the susceptible parent, Way Rarem, suggesting an epistatic effect. This is the first QTL reported in rice having a large and repeatable effect on grain yield under severe drought stress in the field.
Does polyploidy occur in central European species of the family Sphaeriidae (Mollusca: Bivalvia)?
Authors: Kořínková Tereza , Morávková Alena 
Published: July 2010

Abstract
Some representatives of the bivalve family Sphaeriidae are assumed to be polyploid. In this study, 11 sphaeriid species (nine of the genus Pisidium, one of Musculium, and one of Sphaerium) inhabiting central Europe were studied karyologically, 10 of them for the first time. Analysis revealed high chromosome numbers (from 140 to 240). To elucidate the origin of high chromosome numbers, DNA contents were measured by flow cytometry in 5 of the studied species and, for comparison, in S. corneum and S. nucleus, which are known to be diploid (2n=30). Species with high chromosome counts yielded very similar DNA contents that are not higher than in the related species with low diploid numbers. This finding contradicts a possible origin of these species by recent polyploidization or hybridization of related species. Chromosome complements of the investigated species with high chromosome numbers differ from those with low 2n in their small chromosome size and the high proportion of subtelo- or acrocentric chromosomes. This indicates their possible origin either by an ancient polyplodization event followed by chromosomal rearrangements or by multiple chromosome fissions.
Morphometry of non-native black bullhead Ameiurus melas from Slovakia
Authors: Novomeská Andrea , Kováč Vladimír , Katina Stanislav 
Published: July 2010

Abstract
The study on the external morphology of the non-native black bullhead (Ameiurus melas) was carried out on a population from Slovakia, based on triple regression and geometrical analysis. The breakpoints distribution in distance-based morphometric characters indicated that black bullhead reached its definitive phenotype early in ontogeny. Ontogenetic changes in external morphology occurred continuously throughout the whole size-range of the sample examined, and inter-individual morphological variation was very low. Such uniformity may reflect the possible founder effect and/or little phenotypic plasticity of this non-native population. No sexual dimorphism was observed. This is the first detailed study on external morphology of the species, and as such it contributes to the assessment of phenotypic plasticity and/or overall morphological variability of black bullhead’s invasive populations.
More female red foxes Vulpes vulpes on bait sites in spring
Authors: Galby Jens , Hjeljord Olav 
Published: July 2010

AbstractThe red fox Vulpes vulpes has traditionally been subjected to control efforts throughout much of its range. In this article, we present data on the sex and age composition of red foxes culled at bait sites in an area of southeastern Norway. While an excess of males were shot in early and mid‐winter, equal proportions of males and females were shot in early spring. Apparently, females are more nutritionally stressed in March due to pregnancy and therefore visit bait sites more frequently. Culling earlier in winter will predominantly remove males and will bias the sex composition in the population towards females.
Nest predation in declining populations of common eiders Somateria mollissima: an experimental evaluation of the role of hooded crows Corvus cornix
Authors: Stien Jennifer , Yoccoz Nigel G. , Ims Rolf A. 
Published: July 2010

AbstractWe evaluated the effect of the removal of hooded crows Corvus cornix on common eider Somateria mollissima nesting success using a partial Before and After Comparison of Impact (BACI) design over three years in two eider breeding colonies (Håk⊘ya and Grind⊘ya) in northern Norway. These breeding colonies had over the last decades been subject to severe declines in number of breeding birds and it was suspected that increasing nest predation by crows was contributing to the declines. Eider nesting success was monitored in both colonies during 2006‐2008. Crows were removed by live‐trapping from Håk⊘ya in 2007 and from Grind⊘ya in 2008. We monitored the number of nesting pairs of crows and general crow activity. Crow removal was generally successful in reducing the number of established territorial and visiting crows. Modelling of daily nesting success probabilities according to a logistic exposure model revealed that eider nests found at the start of the season had a much lower probability of success than nests found later on in the season. This is likely to be due in part to the increase in number of active nests during the first half of the season. The effect of crow removal appeared to differ between the two colonies. Eider nesting success on Håk⊘ya increased from 61% in the pre‐removal year 2006 to 80% during crow removal in 2007 and declined to 74% in the post‐removal year 2008. In contrast, nesting success on Grind⊘ya remained constantly low (38‐40%) during the same period. This difference between the two colonies could be explained by a difference in predation pressure, or by a higher general disturbance level on Grind⊘ya making unattended nests vulnerable to predation by a range of alternative predator species acting compensatory to the removal of crows. New investigations should be undertaken to clarify the interaction between crows and other nest predators in determining eider nesting success. Where compensation appears to occur, conditions for this process should be investigated. This will help to indicate when crow removal can be effective and which other actions can be employed to increase common eider nesting success.