bluuebunny/crossref_metadata_2025_split huggingface dataset:
Changes in Nonstructural Carbohydrate Fractions of Developing Spring Wheat Kernels1
Authors: Escalada J. A. , Moss Dale N. 
Published: July 2010

Nonstructural carbohydrate fractions were studied at four stages of kernel development of wheat (Triticum aestivum L. em. Thell.) to quantify the amounts present and differentiate sucrose from the glucofructan (GF) fractions. We accomplished this by using different ethanol concentrations to extract different oligosaccharide fractions followed by hydrolysis with acid or incubation with takadiastase enzyme. Concentrations of ethanol from 100 to 60% yielded steadily increasing perc.entages of nonstructural carbohydrates, indicating a series of GF of increasing chain length. Glucose to fructose ratios of 1:14 were found in GF extracted with 60% ethanol from the residue of the 70% ethanol extraction.Carbohydrate content/kernel gave a clearer picture of nonstructural carbohydrate changes with maturation of the grain than did concentration. The glucose, fructose, and glucofructan contents reached maxima before the phase of rapid starch synthesis, but then decreased as the kernels matured. Sucrose content, however remained high during the rapid phase of starch accumulation before decreasing at Kernel maturity.
Temperature Requirements for Growth of Grass‐clump Dwarf Wheats and the Inheritance of the Trait1
Authors: McVetty P. B. E. , Canvin David T. , Hood C. H. 
Published: July 2010

Grass clump dwarf wheat plants (Triticum aestivum L. em Thell.) are characterized by their reduced stature, increased tiller number, and frequent lack of reproductive growth. Three types of grass‐clump dwarf wheat plants occur in the progeny of crosses of normal wheat cultivars. Temperature has been shown to have a dramatic effect on the growth of the most severe dwarf but its effect has not been investigated with the less severe dwarf types. On the other hand, the inheritance of the trait has been most studied with the less severe dwarf types. In this study the temperature requirement for normal growth of the three types of grass‐clump dwarfs and the inheritance of the trait was determined.Crosses of several common wheat cultivars were made and the F1's were grown in controlled environmental growth cabinets under conditions of continuous 16,146 to 18,299 lux incandescent/fluorescent illumination and constant temperature regimes of 11, 16, 21, and 26 C.In general, type 1 dwarfs grew normally at temperatures of 26 C or higher, type 2 dwarfs grew normally at 21 C or higher, and type 3 dwarfs grew normally at 16 C or higher. At temperatures below these values, the characteristic grass‐clump dwarf morphology was displayed in plants possessing a dwarfing genotype.Conventional genetic analysis of F2 populations and F3 lines showed that a three complementary dominant gene system adequately explained and predicted the origin of grass‐clump dwarfs in inter‐class wheat crosses.
Organic Acid Composition of Tall Fescue Leaves from Diverse Genotypes1
Authors: Boland R. L. , Garner G. B. , Asay K. H. , Nelson C. J. 
Published: July 2010

Organic acids are important plant metabolites and have been associated with palatability and forage quality. Gas‐liquid chromatography was used to quantify nine organic acids in leaves of 22 genetically diverse tall fescue (Festuca arundinacea, Schreb.) genotypes grown in a greenhouse. Significant differences (p < 0.01) were found among genotypes in concentration of malic, citric, x‐ketoglutaric, succinic, malonic, quinic, shikimic, and total of the nine acids. Malic acid was most abundant in 19 genotypes and averaged 9.3 mg/g dry wt, followed by citric, succinic, quinic, and shikimic acids with 4.4, 3.6, 3.5, and 2.6 mg/g dry wt, respectively. Concentrations of fumaric and aconitic were usually less than 0.1 mg/g dry wt. A genotype selected from ‘Ky 31’' had 19.3, 6.6, and 38.8 mg/g dry wt of malic, citric, and total of the nine acids, respectively. In contrast, a genotype from Algeria had 3.5, 1.2, and 15.1 mg/g dry wt for the same fractions.Malic acid concentrations were positively correlated (p < 0.01) with quinic, shikimic, and citric acid levels. Succinic acid was positively correlated with a‐ketoglutaric acid, and shikimic acid was positively correlated with quinic acid. The genetic variability observed indicates organic acid content of tall fescue leaves could be altered through breeding.
Effect of Water Stress on 14CO2 Fixation and Translocation in Wheat during Grain Filling1
Authors: Johnson R. R. , Moss Dale N. 
Published: July 2010

Field canopies of two semi‐dwarf wheat (Triticum aestivum L.) genotypes were subjected to water stress that caused visible wilting during the grain filling stage to determine the distribution of photosynthesis within the canopies and the pattern of translocation of labeled assimilates following 14CO2 uptake. The stress treatment caused a 14% reduction in kernel weight and a 20% reduction in grain yield compared to control plants.Plants in the control and stress plots were exposed to 14CO2 at 12, 16, and 23 days after heading. During this time, the severity of stress increased on the stress plots. Under water stress, the site of photosynthesis tended to shift away from leaf lamina to the upper leaf sheaths, upper portions of the stem, and the spike.Within 24 hours after labeling, the majority of the 14C had been transloeated from leaves and sheaths; in stressed plants 46% of the 14C (averaged over genotypes and dates of exposure) was found in the grain compared to 35% in control plants. Of the total 14C recovered from shoots at maturity, 83% was found in the grain of stressed plants and 69% in control plants. The lower percentage of 14C in grain of control plants at maturity was due to accumulation of 14C in stem segments, primarily in the form of structural carbohydrates.As the lower leaves became senescent, the relative contribution of spikes, upper sheaths, and stems to total photosynthesis increased. The percentage of the present in the grain at 24 hours and at maturity was greatest when 14CO2 was fixed later in the grain filling period.
Selection for Early Flowering in Corn: Seven Late Synthetics
Authors: Troyer A. F. , Brown W. L. 
Published: July 2010

Seven corn (Zea mays L.) synthetics adapted to southern Iowa were grown in southern Minnesota at high plant density, and the earliest 5% to flower were sibmated for five generations. The original populations and the five selected cycles were then compared in performance trials at three plant densities over 2 years. Selection effect per cycle averaged: 1.1 q/ha yield increase, 2.2 ears/100 p.lants increase (1‐year data), 1.6 percentage points grain moisture decrease, 2.8% stalk breakage increase, 6.1 cm plant height decrease, 4.1 cm ear height decrease, 1.7 days less to flower, and 0.4 days less silk delay.We observed a cycle‐by‐density interaction wherein advanced cycles exhibited prolificacy at a low density after selection against barrenness at high densities. The decrease in silk delay and increase in ears per plant indicate that selection for early flowering during stress is effective in adapting materials to high plant densities.Flowering date is highly heritable and responds readily to selection. Selection for early flowering is an effective way to adapt late corns to an earlier area. It provides more genetic divergence than the pedigree method or other breeding schemes that use early germplasm as donor of maturity genes.Strong correlated responses to selection for early flowering were found for lower kernel moisture, lower plant and ear height, and higher stalk breakage.Earlier flowering increased yields among late flowering corns and decreased yields among early ones. Earlier flowering increased yields in a short, cool season and decreased yields in a long, warm season. These phenomena can be explained by the contrasting relationships of flowering date with plant size and length of grain filling period: earlier flowering increases yield when longer grain filling period is critical and decreases yield when larger plant size is more important.
Use of Progenitor Species Germplasm for the Improvement of a Cultivated Allotetraploid1
Authors: Wernsman E. A. , Matzinger D. F. , Mann T. J. 
Published: July 2010

The suitability of progenitor species germplasm as a source of genetic variation for the improvement of quantitatively inherited genetic traits in a cultivated allotetraploid species was investigated. Tobacco, Nicotiana tabacum L. cv. SC 58 was doubled with colchicine to the octoploid state and crossed with the diploid progenitor species N. sylvestris Speg. and Comes. The partially fertile pentaploid hybrid was selfed, or backcrossed one generation to SC 58, to increase fertility. Two cycles of a recurrent selection scheme using SC 58 as a tester parent were then followed to concentrate desirable germplasm from N. sylvestris in the species‐derived synthetic populations.The two synthetic populations (Syn I and Syn II), 58, S1 families, and testcrosses to SC 58 of plants in Syn I which were used to produce Syn II were evaluated in three environments for 11 agronomic and chemical constituents. Significant differences were detected among genetic entries for all characters measured except percent nornicotine in cured leaf, indicating that germplasm from the diploid species, N. sylvestris, had been introgressed into the N. sylvestris genome of tobacco. The potential value of this genetic variation is demonstrated by the fact that Syn I and Syn II yielded 7.7 and 12.9%, respectively, more cured leaf than SC 58. Thus, the breeding technique may be useful in broadening the genetic base for the improve. merit of quantitatively inherited characters in this cultivated species.
Development of Cotton Fruit. III. Amino Acid Accumulation in Protein and Nonprotein Nitrogen Fractions of Cottonseed1
Authors: Elmore C. D. , Leffler H. R. 
Published: July 2010

This study was conducted to determine the metabolic events occurring during cottonseed development as revealed by N and amino acid compositions of both the whole seed and the free amino acid pool. Flowers on field grown cotton (Gossypium hirsutum L.) plants were tagged the day of anthesis, and bolls were sampled at intervals between 10 days after bloom and maturity. Developing seed were analyzed for both total N and nonprotein N (NPN). While total N was accumulated by the seed throughout development, NPN increased until 21 days after anthesis and then declined. At boll opening, only about 1% of the total N was in the NPN fraction.Amino acid compositions of the seed and the NPN fraction were also determined. In juvenile seed tissue, over 50% of the NPN was accounted for by asparagine. Other amino acids prominent in this free amino acid pool of young cottonseed were, in descending order, glutamine, aspartic acid, glutamic acid, and arginine. At maturity, asparagine and glutamic acid each accounted for about 15% of the NPN. Gamma‐amino butyric acid and ethanolamine were also observed in the NPN fraction. Significant shifts in total amino acid distribution were seen to occur during the fourth week of seed development. The amino acid profile of cottonseed after the fifth week of development closely approximated that of mature seed.
Relationship of Hydroxamic Acid Content in Corn and Resistance to the Corn Leaf Aphid1
Authors: Long B. J. , Dunn G. M. , Bowman J. S. , Routley D. G. 
Published: July 2010

The cyclic hydroxamate, 2,4‐dihydroxy.7‐methoxy‐l,4‐benzoxazin‐ 3‐one (DIMBOA), has been implicated in the resistance of corn (Zea mays L.) to fungi and insects. In our study, bioassay and field experiments tested the relationship between hydroxamate concentration and resistance to corn leaf aphid (Rhopalosiphum maidis (Fitch)).In the bioassay, various concentrattons of DIMBOA were added to an artificial diet fed to corn leaf aphids. DIMBOA concentrations of 0.1, 0.25, and 0.5 mg/g diet caused 5.1, 12.8, and 20.8% mortality, respectively. In field trials, 12 inbred lines were evaluated for corn leaf aphid resistance under natural infestation. Aphid infestation was evaluated at mid‐silking stage with a visual rating scale and index system. Cyclic hydroxamate concentration in a separate set of the same lines was estimated by a rapid procedure based upon the colorimetric reaction of hydroxamates with ferric chloride. Aphid infestation values ranged from 119 to 366. Hydroxamate concentration ranged from 0.08 to 1.48 mg/g fresh weight. A highly significant correlation (r = 0.72) was obtained between aphid infestation and hydroxamate concentration.Eighteen hybrids derived from crosses among 12 inbred lines were also evaluated for corn leaf aphid resistance in the field. Aphid infestation values from high ✕ high, intermediate ✕ intermediate, and low ✕ low DIMBOA lines were generally low, intermediate, and high, respectively. Hybrids derived from crossing high ✕ low, high ✕ intermediate, and intermediate ✕ low DIMBOA lines produced infestation values between the parental extremes.
Role of Multiple Awns in Determining Barley Yields1
Authors: Rasmusson D. C. , Crookston R. K. 
Published: July 2010

We developed barley (Hordeum vulgare L.) lines differing in number of awns to learn if yield would be increased by the presence of additional awn tissue. Experimental procedures included field experiments conducted over several years, and structural characterization of awn tissue by light and scanning electron microscopy.In “multiple awn” lines the glumes are the size of lemmas and have an awn at their apex. These lines therefore contain three awns per spikelet, compared to one awn per spikelet in normal awned lines. Glume awns are structurally similar to normal awns and possess stomata which appear to be functional. The multiple awn lines had 46% more awn tissue by weight, and 76% more by length, than ‘Dickson’. The large glumes supporting the extra awns had six and‐a‐half times the surface area of normal glumes.The multiple awn lines produced lower grain yields than normal awn lines. Yields ranged from 50 to 88% of Dickson. At least three factors appeared to be involved in the yield decrease; the multiple awn lines were less robust, they had an average of 15 fewer kernels/head, and their kernels were 10% lighter (indicating the absence of component compensation). The reduced plant size suggests that the multiple awn gene affects overall plant growth. We postulate competition for substrate during floral initiation and development to explain the marked reduction in kernel number. The reduced kernel weight presumably means that the extra awns and large glumes had a net negative effect on photosynthate deposition in the kernel.
Sorghum Root Morphogenesis and Growth. I. Effect of Maturity Genes1
Authors: Blum A. , Arkin G. F. , Jordan W. R. 
Published: July 2010

Root development of two sorghum [Sorghum bicolor (L.) Moench.] maturity isogenic lines (early – 60 SM and late – 100 M) was closely studied in plants growing up to 38 days after emergence (DAE) in hydroponics. Each adventitious (crown) root was tagged upon appearance and periodically measured for length. Root diameters, root volume, leaf area, and transpiration were also measured periodically. Seminal roots and mesocotyls were removed on some plants at 10 DAE, in order to simulate the effect of some common fungal or insect damage in the field.The onset of initiation of adventitious roots occurred at 4 and 6 DAE in the early and late genotypes, respectively. Root initiation rates cycled with time, within a range of 0 to 1.5 roots‐plant‐l−day−1. Cycling of root initiation rates appeared to correspond with the formation of concentric whorls of these roots in the crown. Total number of adventitious roots at 38 DAE was 17 and 23 in the late and early genotypes, respectively. In the early genotypes, growth rate of adventitious roots that were initiated at an early stage was the same as for roots initiated later, being about 3 cm day−1 In the late genotype, growth rate of later initiated roots was slower than that of roots initiated earlier. Although the early genotype had a greater total adventitious root length per plant than the late one, the latter had a greater root volume than the former, due to greater number and growth of lateral branches.Removal of the seminal root and mesocotyl increased the number and growth of lateral branches of existing adventitious roots and subsequently increased root volume in the early genotype. Similar effects were not observed in the late genotype.
Nodulation of Soybeans Grown Hydroponically on Urea1
Authors: Vigue J. T. , Harper J. E. , Hageman R. H. , Peters D. B. 
Published: July 2010

Soybeans [Glycine max (L.) Merr.] were grown hydroponically to determine the effects of urea‐ and nitrate‐N sources on nodulation. Urea allowed effective nodule development and function, as evidenced by nodule mass, acetylene reduction, and difference between the total Kjeldahl N gain per plant and urea uptake measurements. Plants grown in solutions with as high as 18 mM urea‐N produced nodules capable of N2 fixation (C2H2 reduction assay) while NO3 concentrations low as 2 mM inhibited nodulation. The amount of N fixed by nodules of plants grown on urea varied from 27 to 71% of total plant N, depending on urea concentrations of the nutrient solutions.Urea uptake by the plants was slower than NO3 uptake, regardless of urea concentration supplied. Therefore, internal concentrations of N or N‐components in the plant were likely lower with urea than with NO3 nutrition which may have partially accounted for the degree and effectiveness of nodulation. Growth on urea is a convenient hydroponic method of producing healthy, vigorous, nodulated soybeans that are capable of N2 fixation.
Path Coefficient Analysis of Sugarbeet Purity Components1
Authors: Smith G. A. , Martin S. S. , Ash K. A. 
Published: July 2010

An analysis of the association of 10 chemical and agronomic characters with purity in three sugarbeet (Beta vuigaris L.) genotypes was used to develop models to identify the components having the greatest effect on purity.Potassium, betaine, and Na followed by NO3‐N, amino N, and sucrose were the most important variables in the 12 best models developed to explain purity. R2 values (percentage of ascribed variation in purity) for these 12 best models ranged from 89.5 to 94.7%. Soluble nonsucrose constitutents increased in quantity from high plant population density to low density, but this linear change did not greatly affect models constructed to account for juice purity either at regular or low N fertility.
Protein Quality of Triticale. I. Early Generation Selection for Protein Efficiency Indices1
Authors: Knoblauch C. J. , Elliott F. C. 
Published: July 2010

The feasibility of selection for protein efficiency indices (PEI = grams body weight gain per protein consumed) in the early generations of a breeding program was studied with selected winter triticale (✕ Triticosecale Wittmack) lines. Weanling vole (Microtus pennsylvanicus) bioassays of seed from F3 plants along with several F4 plant selections from each F3 indicated that selection for protein efficiency indices was practical as early as the F3 generation.The evacuation period used to simulate beginning caecal weight reduced PEI values appreciably; however, only minor changes in ranking were found. Caecal accumulation had little effect other than increasing cereal protein efficiency indices without negating the nutritional comparisons among the early generation triticale lines tested.
Protein Quality of Triticale. II. Prediction of Protein Efficiency Indices Through Chemical Analyses1
Authors: Knoblauch C. J. , Elliott F. C. , Penner D. 
Published: July 2010

Several chemical determinations of triticale (✕ Triticosecale Wittmack) meals have shown promise of predicting protein efficiency indices (PEI = g body weight gain per g protein consumed) as determined by Microtus bioassay. The percent water‐soluble protein (pH 4.9), total trypsin units inhibited (total TUI, adjusted for percent water‐soluble protein), and extracted dye‐binding capacity (DBC completed after removal of water‐soluble proteins) showed the highest correlations with PEI. A group of 42 F4 winter triticale plants representing seven F4 plants from each of two high F3 PEI plants, two average F3 PEI plants and two low F3 PEI plants, were analyzed. The correlations with PEI were −0.45, −0.53, and 0.66 (P<0.01) for percent water‐soluble protein, total TUI, and extracted DBC, respectively. The multiple correlation coefficient utilizing total TUI and extracted DBC was 0.74**.A group of 20 F3 plants selected for high and low PEI values gave even more predictable responses. Their correlations with PEI were −0.71, −0.79, and 0.66 for percent water‐soluble protein, total TUI, and extracted DBC, respectively. The multiple correlation coefficient for the regression of extracted DBC and total TUI on PEI was 0.86**, indicating that 75% of the variation in PEI was accounted for by the two independent variables.
Floral Induction and Initiation in Kentucky Bluegrass Cultivars1
Authors: Canode C. L. , Perkins Merlin 
Published: July 2010

This research was designed to study induction and floral initiation of 11 cultivars of Kentucky bluegrass (Poa pratensis L.). Spring‐seeded plants were in the vegetative condition when exposed in autumn to inductive environment (cool temperatures and short photoperiods). Floral initiation was determined by 1) biweekly dissection of tillers and by 2) biweekly transfer to warm temperature and long photoperiod to force panicle production.Dissection of tillers showed no transition to floral development from early November, 1974, to 4 Jan., 1975. Transition to floral primordia was. apparent for ‘Merion’ and ‘Newport’ on 27 January, six cultivars on 10 February, and all 11 cultivars on 25 February. ‘Cougar’, ‘Fylking’, and ‘Glade’ require a longer induction period than the other cultivars before floral initiation.Transfer of plant material from field inductive conditions to warm temperature and long photoperiod in a greenhouse indicated that induction had not occurred before 18 November. Panicles were produced by ‘Arista’, ‘Baron’, ‘Garfield’, and Newport when transferred on 2 December and by an additional four cultivars when transferred on 16 December. Glade and Fylking did not produce panicles until the transfer was made on 27 January, again indicating the longer induction period necessary for these cultivars. Induction and floral initiation, as measured by panicle production, increased in linear association (r = 0.98**) with duration of time plants were left under inductive conditions.Either method of study, tiller dissection or transfer to artificial environment, has advantages and disadvantages. This research indicates that the two methods are complementary and valuable to understanding induction and development of floral primordia when used concurrently.