bluuebunny/crossref_metadata_2025_split huggingface dataset:
Response of Kernel Weight of Sorghum to Environment Early and Late in Grain Filling
Authors: Kiniry J. R. , Musser R. L. 
Published: July 2010

AbstractSorghum [Sorghum bicolor (L.) Moench] is grown in a wide range of moisture and temperature environments because it is drought and heat resistant and has a relatively high yield potential. Describing the influence of reduced photosynthesis and increased temperature during grain filling on mean kernel weight (KWT) is a prerequisite to understanding the control of productivity in sorghum. Objectives of this study were to determine if decreased available assimilate due to reduced photosynthetic photon flux density (PPFD) during early grain filling reduces KWT by reducing the number of endosperm cells, and to investigate the effect of temperature on KWT and number of starch granules after endosperm cell division is complete. Plants of a single‐seeded hybrid (Hl) and a twin‐seeded hybrid (H2) were grown until heading in a greenhouse. From heading until 10 to 12 d after anthesis, plants were in growth chambers with PPFD of either 300 or 595 μmol m−2 s−1. Thereafter, plants were in chambers at 15, 22.5 or 30 °C until maturity. Measurements included seed volume and number of endosperm cells at the end of the PPFD treatments, and number of starch granules and KWT after maturity. Low PPFD early in grain filling did not decrease KWT of either hybrid although it reduced number of endosperm cells of H1 by 47%. The 30 °C treatment reduced KWT by 29% for both hybrids relative to the 22.5 °C treatment. Likewise, the 30 °C temperature reduced number of starch granules at maturity, It appeared that reduced production of starch granules contributed directly to reduced KWT at 30 °C.
Growth, Water‐Use Efficiency, and Digestibility of Crested, Intermediate, and Western Wheatgrass
Authors: Frank A. B. , Karn J. F. 
Published: July 2010

AbstractRelationships between dry matter distribution among plant components, growth rates, in vitro digestible organic matter (IVDOM), and water‐use efficiency (WUE) have not been defined for cool‐season wheatgrass species grown on the Northern Great Plains. Three cultivars each of crested wheatgrass [Agropyron desertorum (Fisch. ex Link) Schult.], intermediate wheatgrass [Elyfrigia intermedia (Host) Nevsk: Syn: A. infermedium (Host) Beauv.], and western wheatgrass (Pascopyrum smithii (Rhdb.) Love Syn: A. smithii Rydb.] were field grown and sampled over a 3‐yr period to define these relationships. The soil was a Parshall fine sandy loam (coarse‐loamy, mixed Pachic Haploboroll). Forage was harvested at three dates to measure IVDOM, WUE, forage yield, leaf area index (LAI), and leaf and stem dry matter. Significant differences were mainly present among cultivars of western wheatgrass compared to those of crested and intermediate wheatgrass. ‘Rodan’ western wheatgrass partitioned more dry matter into stems than leaves, which resulted in lower LAI, leaf/stem ratio (LSR), and IVDOM. However, Rodan had higher WUE and forage yield than did ‘Flintlock’ and ‘Rosana’ western wheatgrass. Although forage yield and IVDOM differed among western wheatgrass cultivars, there were no differences in total digestible organic matter. Growth analysis showed Rodan western wheatgrass to be more efficient than Flintlock and Rosana in accumulation of dry matter per unit of photosynthesizing leaf surface. These results suggest that partitioning of dry matter into leaves and stems is a primary factor in determining WUE and digestibility, especially for western wheatgrass.
Injury and Yield Responses of Differentially Irrigated Cotton to Ozone
Authors: Temple P. J. , Kupper R. S. , Lennox R. W. , Rohr K. 
Published: July 2010

AbstractThe hypothesis that plants subjected to drought stress should be less susceptible to air pollution than well‐watered plants has not been adequately tested in the field. This study was conducted to determine the influence of drought stress on foliar injury and yield responses of field‐grown cotton (Gossypium hirsutum L. cv. Acala SJ‐2) to O3. Cotton grown on Hanford coarse sandy loam (coarse‐loamy, mixed, non‐acidic, thermic Typic Xerorthents) at three levels of soil water in open‐top chambers was exposed to seasonal 12‐h (0900‐2100 h) O3 concentrations of 0.015, 0.074, 0.094 and 0.111 μL L−1 in Riverside, CA. At ambient O3 concentrations (0.074 μL L−1) severely drought‐stressed (SS) cotton averaged 25% foliar injury, while moderately stressed (SO) plants averaged 56%, and optimally watered (OW) plants averaged 68% foliar injury. Lint and seed yields were significantly reduced by O3 in OW and SO plots, while SS cotton showed no yield reductions, except at 0.111 μL L−1. Yield reductions were primarily attributable to fewer numbers of bolls. Regression equations for lint yield in relation to seasonal 12‐h O3 means and total seasonal irrigation predicted yield losses at ambient O3 concentrations relative to a background O3 level of 0.025 μL L−1 of 26.2% for OW, 19.8% for SO, and 4.7% for SS cotton. The relative similarity in responses of OW and SO cotton was attributed to adaptation to drought stress by SO plants, which maintained the sensitivity of moderately stressed cotton to O3. These results suggest that low or moderate drought stress would have relatively little effect on the response of irrigated cotton to O3.
Field Evaluation of Two Urease Inhibitors with Transplanted Lowland Rice
Authors: Buresh R. J. , De Datta S. K. , Padilla J. L. , Samson M. I. 
Published: July 2010

AbstractThe amendment of urea with a urease inhibitor has been proposed as a strategy to increase yield of lowland rice (Oryza sativa L.) through the reduction of N loss by ammonia volatilization. Field studies were conducted at two locations in the Philippines to determine the effects of two urease inhibitors, phenyl phosphorodiamidate (PPD) and N‐(n‐butyl) thiophosphoric triamide (NBPT), on N uptake and yield of rice. Urea was split applied at 16 to 18 d after transplanting (DT) and at 5 to 10 d after panicle initiation (DAPI). On a silty clay soil (Vertic Tropaquept) at Muñoz, the amendment of urea with PPD or NBFT significantly increased grain yield relative to conventional urea (P = 0.05). Agronomic efficiency for 35 kg N ha‐' increased from 43 kg grain kg−1 fertilizer‐N for urea to 51 and 52 kg grain kg−1 fertilizer‐N for urea + 20 g PPD kg−1 and urea + 9 g NBPT kg−1, respectively. Both PPD and NBPT increased grain N, averaged for four non‐zero N rates, by 5.7 and 7.8 kg ha−1, respectively. The increased uptake of N with the inhibitors occurred prior to 35 DT; subsequent N uptake was not affected. On a clay soil (Andaqueptic Haplaquoll) at Pila, the addition of inhibitors failed to give significantly greater grain yields than unamended urea in each of the three experiments. However, the quadratic response models for urea and urea + PPD obtained from combined results for the three Pila experiments were significantly different (P = 0.01). Amendment of urea with PPD increased agronomic efficiency by 4 kg grain kg−1 urea‐N. Physiological efficiency (kg grain kg−1 N uptake) was not significantly affected by the inhibitors, which suggests that an increase in N uptake with the inhibitors resulted in a corresponding yield increase. This study indicates that urease inhibitors can increase grain yield of lowland rice, but the yield increases with inhibitors might be small.
Temperature and Photoperiod Interactions with the Phenological Development of Sunflower
Authors: Goyne Philip J. , Schneiter A. A. 
Published: July 2010

AbstractThe synchronization of anthesis of sunflower (Helianthus annuus L.) genotypes to be crossed is important for seed production. Little information is available concerning the interaction of temperature with photoperiod on the phenological development of sunflower. Research was conducted in growth chambers to determine the influence of variations in temperature, photoperiod, and light quantity on the phenological development of 16 sunflower genotypes. The sunflower genotypes were subjected to light treatments of: (i) 12‐h fluorescent and incandescent light, (ii) 14‐h fluorescent and incandescent light, and (iii) 12‐h fluorescent and incandescent light followed by 2‐h exposure to incandescent lights only. The fluorescent‐incandescent light combination provided a photosynthetic photon flux density (PPFD) of about 430 μmol m−2 s−1 in the chambers, whereas that for the incandescent lights alone was 5 μmol m−2 s−1. All light treatments were imposed under day/night temperature regimes of 18/15 and 28/22°C. The light X temperature X genotype interaction was not significant. Light X genotype and temperature X genotype interactions were highly significant for number of days from emergence (VE) to bud visible (R1) and number of leaves at R1. Other significant interactions were temperature X genotype for number of leaves and plant height at R1, and light X genotype for plant height. Some of the genotypes exhibited substantial delay in reaching R1 under the 12‐h light treatment, confirming prior observations in greenhouse plantings. Differences in light energy levels had little influence on genotype photoperiodic behavior.
Decreased Rates of Nitrate Uptake During Pod Fill by Cowpea, Green Gram, and Soybean
Authors: Imsande John , Edwards D. G. 
Published: July 2010

AbstractGrain legumes derive their seed‐N from soil‐N uptake, remobilization of plant‐N, and N2 fixation. To establish the profile of nitrate uptake and the contribution made by soil‐N uptake during pod fill, non‐nodulated plants were grown in solution culture, and net rates of nitrate‐N uptake were measured throughout the plant growth cycle. Green gram [Vigna radiata (L.) Wilzek cv. Berken], cowpea [Vigna unguiculata (L.) Walp. cv. Ife Brown], and soybean [Glycine max (L.) Merr. cvs. Bragg and Harosoy] were utilized in these studies. At physiological maturity, plants were harvested and dry weight and N content were measured. For the determinate legumes, green gram and Bragg soybean, seeds represented approximately 25% of the total plant dry weight and contained approximately 45% of the total plant‐N. For the indeterminate cowpea and Harosoy soybean, seeds accounted for approximately 35 to 40% of the total plant dry matter and contained approximately 50 and 70%, respectively, of the total plant‐N. The fraction of nitrate‐N taken up after the onset of pod fill ranged from approximately 20% for the determinate to 30% for the indeterminate cultivars. Thus, it can be calculated that a maximum of approximately 50% of the total seed‐N for each of the four cultivars was derived directly from nitrate‐N uptake during pod fill, and the remaining 50% came from mobilization of N in vegetative tissue.
Methodology for Evaluating Nitrogen Utilization Efficiency by Rice Genotypes
Authors: De Datta S. K. , Broadbent F. E. 
Published: July 2010

AbstractLow prices for rice (Oryza sativa L.) have placed farmers all over the world in a cost‐price squeeze. There is an urgent need for cultivars and production technology that will help increase yield at lower monetary costs. A method is proposed for evaluating N utilization efficiency among rice genotypes by various combinations of plant parameters, and to rank their performance in the field. From field experiments on an Andaqueptic Haplaquoll soil in six consecutive seasons, a ranking procedure was devised that does not require the use of isotopically labeled fertilizer, which makes it less expensive and more widely applicable than a similar procedure described previously. The criteria for ranking genotypes were based on differences in several plant parameters in six seasons, in three of which 33 genotypes were grown and in three when 24 genotypes were grown. Statistically significant differences among genotypes were found in 52 out of a possible 60 instances involving five selected parameters over six seasons in nonfertilized and fertilized plots. From among these five parameters, grain yield (Y) and panicle weight per total N uptake (WP/Nt) were selected by analysis of data for 12 genotypes common to all six seasons of the experiment. Genotypes such as IR21912–56–3–1–2–2 and IR15323–78–1–3–1 had consistently high rankings with and without fertilizer N and in both wet and dry seasons. Growth duration of genotypes was a factor in the differences among genotypes. Most of the high‐ranking genotypes were of medium or long duration. A satisfactory evaluation of N utilization efficiency can be obtained without the use of isotopically labeled fertilizer. Advanced breeding lines can be routinely screened for their N utilization efficiency, a valuable trait of rice for resource‐poor farmers.
Phosphorus Stress Effects on Growth and Seed Yield Responses of Nonnodulated Soybean to Elevated Carbon Dioxide
Authors: Cure Jennifer D. , Rufty Thomas W. , Israel Daniel W. 
Published: July 2010

AbstractThe influence of P availability on plant responses to elevated atmospheric CO2 concentrations has received limited research attention. Therefore, an experiment was conducted to examine the effect of a wide range of P availabilities on plant response to enriched atmospheric CO2. Nonnodulating soybean [Glycine max (L.) Merr., ‘Lee’] plants were grown from germination to maturity in controlled environment chambers at 350 or 700 μL L−1 CO2 and supplied with a complete nutrient solution containing either 0.005, 0.10, 0.25, 0.50, or 1.00 mM P. Growth and seed yield were maximized at the 0.25 and 0.50 mM P concentrations at 350 and 700 μL L−1 CO2, respectively. Growth and yield were significantly increased by CO2 enrichment at all except the lowest P concentration. The stimulation of growth at high CO2 was consistently associated with increased leaf area, net assimilation rate, P uptake, and P utilization efficiency in the production of dry matter. When averaged over the four highest P levels, total root mass was increased 63% by CO2 enrichment, but P uptake efficiency per unit root mass was decreased 22%. The yield enhancement of 23 to 57% at high CO2 was associated with increases in the number and size of seed. Carbon dioxide enrichment had no significant effect on harvest index. The results indicate that CO2 enrichment can result in stimulation of growth and yield of nonnodulated, NO−3‐fed soybean plants, even at concentrations of P that limit plant growth at ambient CO2 concentrations.
Optimizing Soil and Fertilizer Nitrogen Use by Intensively Managed Winter Wheat. I. Crop Nitrogen Uptake
Authors: Baethgen W. E. , Alley M. M. 
Published: July 2010

AbstractInformation is lacking on the N uptake pattern of intensively managed soft red winter wheat (Triticum aesrivum L.) in the mid‐Atlantic region of the United States. Such information would facilitate decision making for N fertilizer management, increase the precision of simulation models used in research, and delineate crop growth stages for use as indicators of plant N needs. Field experiments were conducted in the Atlantic Coastal Plain region of Virginia during the 1981–1982 through 1984–1985 winter wheat growing seasons to describe the winter wheat N uptake pattern and measure responses to N fertilization. The treatments in these experiments consisted of single or split spring N applications at Zadoks growth stages 25 (GS 25) and 30 (GS 30) totaling 0, 90, or 135 kg N/ha. Total dry matter production and total N concentration were measured in the aboveground plant material and in leaves, stems, and heads. These measurements were made shortly after dormancy, at GS 30,45, and 58, and at harvest to assess the effects of the N fertilizer rates and climatic conditions on crop N uptake. Maximum daily N uptake rates were obtained in the period immediately after GS 30, suggesting that this is when the highest efficiency of N fertilizer use could be expected. Crop N uptake at GS 30 also appeared as a potentially good indicator of the plant N requirement. Total amounts of N found in leaves and stems decreased with time during the spring, while spike N increased from the early stages of head development until harvest. Climatic conditions in the different growing seasons affected plant N uptake. Variations in residual soil N and temperatures in early spring probably determined the differences in amounts and patterns of N uptake by whole plants and by the various plant fractions.
A Continuous Two‐Variable Design Using the Line‐Source Concept
Authors: Magnusson D. A. , Asher J. Ben , De Malach Y. 
Published: July 2010

AbstractMultivariable experiments involving different water salinities are usually conducted using drip irrigation. Preparing the irrigation system to apply these different treatments requires a considerable investment of labor and materials. This study was conducted to examine an alternative irrigation system that is relatively simple and inexpensive, yet produces gradients of two variables. A variation of the line‐source irrigation system was tested using water salinity and N levels as variables. The middle line of a triple line‐source irrigated using saline water (7.0 dS m−1)> while the two parallel outside lines irrigated using nonsaline water (1.0 dS m−1). A second triple line‐source using only nonsaline water was superimposed perpendicularly on the first set. Ammonium nitrate was injected into the middle line. This layout produced linear gradients for both variables (r2=0.99) perpendicular to their source and provided every possible combination of saline water concentrations (7.0−1.0 dS m−1) and N levels (8.1−0.0 mmol L−1). It proved to be a simple yet highly informative system.
Flurprimidol Effect on the Emergence and Growth of Annual Bluegrass and Creeping Bentgrass
Authors: Haley J. E. , Fermanian T. W. 
Published: July 2010

AbstractAnnual bluegrass [Pou annua (L.)) and creeping bentgrass (Agrostis palustris Huds.) are major components of golf course turf. The application of the growth regulating compound flurprimidol [α‐(methylethyl)‐ α‐[4‐trifluoromethoxy)phenyl]‐5‐pyrimidinemethanol] might interfere with the emergence and early growth of creeping bentgrass used in overseeding programs, or cause sudden reductions in either species population. Greenhouse experiments were conducted in the summer and winter of 1985 to determine the effects of flurprimidol on germinating seeds and young seedlings of annual bluegrass [P. annua ssp. annua (L.) Timm.] and creeping bentgrass (A. palustis Huds. ‘Penneagle’). Seeds of each species were sown in pots filled with sterilized Flanigan silt loam (fine, montmorillonitic, mesic Aquic Argiudolls) soil. Flurprimidol (0.6, 0.8, 1.1, and 2.3 kg ai. ha−1) was applied preemergence or postemergence to plants 3 to 6 cm in height. Verdure collected 6 wk following treatment showed a significant decrease in yield (25 to 94% of the weight of untreated seedlings) of seedlings of both species treated with flurprimidol prior to or after emergence regardless of rate. Correlation between verdure and flurprimidol rate were significant (0.51 to 0.71) for both species and application timings in both experiments. Injury to both species observed 6 wk following treatment was similar based on visual estimates of color with severe injury (>6) occurring at rates greater than 1.1 kg a.i. ha−1 in the summer experiment. Similar injury was observed in the winter experiment for both species when flurprimidol was applied postemergent. While the effect of flurprimidol at tested application rates was prominent, similar results have yet to be verified through field testing. Thus, turfgrass managers are cautioned to be aware of potential adverse effects of flurprimidol to creeping bentgrass when overseeding.
Boron Effect on Mineral Nutrients of Maize
Authors: Mozafar A. 
Published: July 2010

AbstractBoron deficiency affects the uptake of several elements by plants. Information on the effect of B on yield and nutrient uptake by maize (Zea mays L.) is limited. This sand‐culture study was conducted to acquire information on the long‐term effects of B and interruption of its supply on yield, and the concentrations of 12 elements in earleaf and root of two maize hybrids, Mutin and Carlos Semu 201 (CS 201). Hybrids differed significantly in the concentrations of 11 elements in the earleaves and eight elements in the roots. Increase in solution B concentration increased the concentration of B in the earleaf and root and changed the concentrations of N, P, Mn, Fe, Zn, and Mo in the earleaf and Ca, Mg, Mn, Fe, Zn, Cu, and Mo in the root. Interruption of B supply from tasseling to maturity significantly reduced ear and total yield, decreased B concentration, and altered the concentrations of several other elements in earleaf and root. Significant interactions between B concentration and interruption of B supply, and hybrids with yield and concentrations of several earleaf and root nutrients were observed. Earleaf concentrations of N, K, Ca, Mg, Na, Cu, Mn, and Mo in Mutin, and K, Ca, Cu, and Mo in CS 201 showed significant correlation with earleaf B. Root concentrations of Ca, Fe, and Na in Mutin and Ca, Fe, Mn, and Mo in CS 201 showed correlation with root B. These observations indicate that B, depending on its concentration in the rooting medium, the element under study, and the hybrid, may change the uptake and transport of several other elements in maize. This effect of B, presumed to be due to changes in the membrane transport properties, supports similar findings in other plants. The relationships between the concentrations of K, Ca, Cu, and Mo with the B in the earleaves of both maize hybrids, if proved to hold true under field conditions, indicate that in studies on the uptake of these elements by maize the availability of B in the growth substrate needs also to be taken into account. The confounding effect of B in the rooting medium on the concentration of other elements in the earleaves and in the roots, which could be different for the same element in different hybrids or for different elements in the same hybrid, may partly explain the inconsistency observed by different workers in the yield response of maize to B fertilization.
Forage Preservation Method Influences on Tannin Concentration, Intake, and Digestibility of Sericea Lespedeza by Sheep
Authors: Terrill T. H. , Windham W. R. , Hoveland C. S. , Amos H. E. 
Published: July 2010

AbstractLivestock do not like to graze high‐tannin (HT) sericea lespedeza [Lespedeza cuneata (Dum‐Cours) G. Don], but readily consume it as hay. Intake and digestibility of fresh‐frozen (FF) and field‐dried (FD) HT and low‐tannin (LT) sericea were studied in a feeding trial with sheep (Ovis spp.) in a 2 ✕ 2 factorial with a 4 ✕ 4 Latin square arrangement of treatments. Tannin concentrations were 181,87,31, and 44 g kg‐1 for HT‐FF, LT‐FF, HT‐FD, and LT‐FD sericea, respectively. There was no difference in digestibility due to preservation method, but HT‐FF was less digestible than LT‐FF [forage ✕ preservation method (P < 0.05)]. Digestibility of neutral detergent fiber, acid detergent fiber, hemicellulose, cellulose, lignin, N, neutral detergent insoluble N, acid detergent insoluble N (ADIN), and intake of HT‐FF sericea were lower than LT‐FF or the FD forages. Decreased intake and digestibility of HT‐FF sericea were related to the high tannin concentration. Elevated fecal recovery of lignin and ADIN in sheep fed HT‐FF forage resulted in negative digestibilities and may be related to formation of insoluble tannin‐protein complexes in the digestive tract. Field drying decreased analyzable tannin concentration in HT sericea.