bluuebunny/crossref_metadata_2025_split huggingface dataset:
Soybean Seed Quality in Relation to Days between Development Stages
Authors: Vaughan Duncan A. , Bernard R. L. , Sinclair J. B. 
Published: July 2010

AbstractSeed quality in soybean, Glycine max (L.) Merr., considering infection by seed pathogens, overall visual quality, and seed weight, is affected by date of maturity. We report on the relationship between seed quality, genotype, and late reproductive growth periods and discuss these results in relation to breeding for improved seed quality. The objectives of this study were to: (i) measure seed quality in genetically similar germplasm, but which differ in date of maturity, and (ii) to determine the effects of different reproductive growth periods on seed quality. The field experiments were conducted on Brenton (fine‐silty, mixed, mesic Aquic Argiudolls), Flanagan (fine, montmorillonitic, mesic Aquic Argiudolls) or Proctor (fine‐silty, mixed, mesic Typic Argiudolls) soils at the Agronomy‐Plant Pathology Farm, Univ. of Illinois at Urbana‐Champaign. Delayed maturity in male‐sterile and depodded soybeans resulted in increased seed infection by field seed pathogens probably by lengthening the period during which infection and colonization could take place. Early maturing, maturity isolines were associated with increased infection by Phomopsis spp. which is related to favorable environmental conditions such as warm temperatures and high humidity, which favor spread and growth of this pathogen. A positive relationship was also found between the length of time for late seed fill (Reproductive growth stages R6 to R7) and seed infection by Phomopsis spp.
Growth and Yield of Winter Wheat as Influenced by Chlormequat Chloride and Ethephon
Authors: Cox W. J. , Otis D. J. 
Published: July 2010

AbstractLodging can be a constraint in wheat (Triticum aestivum L.) production, therefore interest exists for use of plant growth regulators (PGRs) such as Chlormequat chloride or CCC (2‐Chloroethyl‐N, N, N‐trimethylammonium chloride) and ethephon [(2‐Chloroethyl) phosphonic acid] for lodging control. Field experiments were conducted in New York in 1985 and 1986 on a Honeoye silt loam (fine‐loamy, mixed mesic Glossoboric Hapludalfs) to examine the influence of CCC (1.37 kg ha−1 a.i. at Zadoks Growth Stage (GS) 31) and ethephon (0.40 kg ha−1 a.i. at GS 39) on vegetative and reproductive growth of two winter wheat cultivars, Geneva and Houser. Leaf, stem, and spike phytomass were determined at 10‐d intervals from GS 25 to 95, and kernel number and weight were determined on 15 main‐culm spikes at 3 to 4‐d intervals during the grain‐filling period. The CCC application reduced culm and total phytomass by 9% at GS 45, whereas ethephon reduced spike and total phytomass by 10 and 8% at GS 55 and GS 75, respectively. Neither PGR had an effect on total or component phytomass at harvest. In 1985, a year when no lodging occurred, ethephon and CCC yielded the same compared with the yield of the check (6.12, 6.60, and 6.39 Mg ha−1, respectively). In 1986, a year of considerable lodging, ethephon reduced lodging compared with that of CCC and the check, which was reflected in a higher kernel growth rate (1.00, 0.84, and 0.81 mg kernel−1 day−1), kernel weight (43.4, 39.8, and 38.9 mg), and grain yield 5.73, 4.71, and 5.30 Mg ha−1, respectively) in the more lodging‐susceptible cultivar, Houser. The data indicate that, under the environmental conditions of this study, CCC does not benefit wheat and that ethephon should be utilized only under severe lodging conditions.
Weather and Seed Quality Variables to Predict Cotton Seedling Emergence
Authors: Kerby T. A. , Keeley M. , Johnson S. 
Published: July 2010

AbstractEmergence of cotton (Gossypium hirsutum L.) seedlings was related to seed quality and temperatures following planting in a 3‐yr field study at Shafter, CA. Environmental conditions for seed production were selected to provide a broad range in seed quality. Seed quality, as determined by the standard germination test and the cool test, was combined with heat units (HU) after planting for predicting field emergence percentage. A total of 74 seed lots (11 in 1984, 39 in 1985, and 24 in 1986) were planted at two different dates, and emergence of 100 seed from each of four replications evaluated. Warm germination percentage (W%) was measured at 30 °C, and ranged between 25 and 90%, cool germination (C%) was measured at 18 °C, and ranged between 1 and 88%, and field emergence percentage ranged from 5 to 98% in these studies. Multiple regression was used to determine the degree of association between variables. Predicting field emergence with C + W% was better than either component alone (r2 = 0.352 for n = 148). The HU (base 60 °F) for 5 or 10 d after planting explained as much variation in field emergence as seed quality (r2 = 0.348 and 0.365), but HU 15 d after planting were not related to field emergence. When HU 5 d after planting, C + W% percentage, and the interaction between the two were considered in multiple regression, 68.5% of the variation in field emergence was explained. With 10 HU 5 d after planting there was a linear increase in field emergence percentage as C + W% increased, but at 25 HU, seed with C + W% of 110 had as many seedlings emerge as lots with C + W% of 175. Eliminating seed lots with warm germination percentages less than 80 from these regressions did not alter the predicted values for field emergence within the range of the data, but did reduce the statistical significance of the relationship. The HU for 5 d can be forecast on the National Oceanic and Atmospheric Administration's (NOAA) weather radio with reasonable accuracy in the San Joaquin Valley of California. If temperatures can be forecast accurately in other regions, cotton growers can adjust seeding rates and plant to a desirable stand, if warm and cool germination percentages of planting seed are known.
Crop Yield as Affected by Rotation and Nitrogen Rate. III. Corn
Authors: Peterson Todd Andrews , Varvel G. E. 
Published: July 2010

AbstractCorn (Zea mays L.) is a widely grown crop in the USA that responds positively to crop rotation. This study compares yields of corn grown in continuous monoculture with that of a (i) 2‐yr soybean [Glycine max (L.) Merr.1‐corn rotation; (ii) a 4‐yr soybean‐grain sorghum [Sorghum bicolor (L.) Moenchj‐oat + clover [Avena sativa L. interseeded with 80% Melilotus officinalis (L.) Lam., 20% Trifolium pratense]corn rotation; and (iii) a 4‐yr oat + clover‐grain sorghum‐soybean‐corn rotation. Interactions between crop rotation and N rate were also determined. The study was conducted for 4 yr on a Sharpsburg silty clay loam (fine, montmorillonitic, mesic Typic Argiudoll). Continuous corn produced less grain (5.5 mg ha−1 yr−1) than corn grown in rotation (7.6 Mg ha−1 yr−1 average). Corn following a legume in rotation produced maximum grain yield with 90 kg N ha−1, while continuous corn required at least 180 kg N ha−1 for maximum yield. Corn following oat + clover produced maximum yield in a year of above‐average precipitation, but this rotation was vulnerable to soil‐water deficits. In 3 of 4 yr, corn following soybean in a 4‐yr rotation produced more grain than other rotations.
Calcium Stimulation of Ammonium Absorption In Radish
Authors: Fenn L. B. , Taylor R. M. 
Published: July 2010

AbstractNitrogen loss processes in soils have been widely studied and there have been many suggestions for improving N‐use efficiency, such as using NH4‐NO3 fertilizers, split fertilizer applications, application timing, and other techniques. The objective of this research was to examine the use of Ca as a means to increase the rate of NH4 absorption by radish (Raphanus sativus L.). Short‐term 15NH4 absorption in the presence of variable Ca was measured in the greenhouse, long‐term plant growth responses to NH4 in the presence of variable Ca were measured both in the greenhouse and in field production trials. Ammonium absorption (15NH4) increased in plants with increasing solution Ca to a Ca/NH4 ratio of 0.5:1 in the tops and to 2:1 in the roots. Vegetative growth increased in two greenhouse experiments as Ca concentrations increased, all at a constant NH4 concentration. As the Ca concentration increased, the total N concentration increased in foliar tissue and decreased in the roots. In the 2 yr of field testing, dry weight yield of roots increased 77 and 55%, respectively, in the urea + Ca treatment compared with the urea treatment alone. In the second year field data, total plant absorption of the added urea‐N in the presence of added Ca increased by 109% compared with urea alone. Significant increases were found both in the root and foliar tissue N content, and growth in the 2 yr of field data. The addition of Ca with urea produced significantly improved plant N‐use efficiency in the field as was suggested from the greenhouse data.
Within‐Row Spacing Influences on Diverse Sorghum Genotypes: II. Dry Matter Yield and Foratge Quality
Authors: Caravetta G. J. , Cherney J. H. , Johnson K. D. 
Published: July 2010

AbstractResearch was conducted to determine changes in dry matter yield, cell wall composition, and digestibility of four diverse sorghum [Sorghum bicolor (L.) Moench.] genotypes as influenced by withinrow spacing. Genotypes (IS‐0469, IS‐0865, P‐954063, and IS‐2952) were selected to represent a range in morphology and cell wall composition, and were sown at five within‐row spacings of 5,10, 15, 30, and 60 cm at two field locations in 1986 and 1987. Harvested herbage was separated into stem, leaf sheath, and leaf blade components for main‐shoot and tillers. Forage dry matter yield declined linearly from 10.9 to 8.1 Mg ha−1 as within‐row spacing increased from 5 to 60 cm. Total forage neutral detergent fiber and permanganate lignin concentrations declined linearly from 717 to 700 g kg−1 and 79.5 to 71.5 g kg−1, respectively, as within‐row spacing increased from 5 to 60 cm. Main‐shoot permanganate lignin concentration in the stem component declined 15.3%, while leaf sheath and leaf blade components were relatively unchanged in lignin concentration with increased within‐row spacing. Total forage in vitro dry matter digestibility and N content increased 8.7 and 16.1%, respectively, as within‐row spacing increased. Reduced plant populations, through increased within‐row spacing, improved forage quality and increased digestibility and protein content, however, dry matter yield was significantly reduced. Within‐row spacing may significantly influence genotype selection for dry matter yield. Genotypic selection for improved forage quality in a breeding nursery should not be greatly affected by within‐row plant spacings of 15 cm or less.
Boll Shedding and Boll Load in Nitrogen‐Stressed Cotton
Authors: Jackson B. S. , Gerik T. J. 
Published: July 2010

AbstractBoll shedding in cotton is thought to depend on the crop growth rate and the demand for plant assimilates by the growing bolls. This study was designed to test the hypothesis that the ratio of boll load (BOLL) and carrying capacity (CA), defined as the maximum boll load, could be used to index the boll shedding fraction for cotton plants with different crop growth rates. Cotton was grown in a greenhouse in 1987 and 1988 with 0, 18, 36, 72, and 144 mmol of N applied at 2‐wk intervals. In 1987, maximum leaf area index (LAI) for the five treatments ranged from 0.6 to 2.2 and maximum BOLL from 5.3 to 23.1 bolls m−2. In 1988, maximum LAI ranged from 1.2 to 4.2 and maximum BOLL from 9.1 to 39.5 bolls m−2. In both years boll sizes for the highest N treatment averaged 4.1 g seed cotton boll−1. Average boll sizes declined for treatments receiving less N, but only the 0 N‐treatment boll sizes were less than 80% of the 144 mmol N treatment. Boll shedding fractions depended on treatments and BOLL. However, for both years boll shedding fractions were highly correlated with the ratio BOLL/CA (R2 = 0.84). Assuming a 1:1 line, the standard error of estimate (SE) was 0.13. Values of CA were highly correlated with maximum LAI (R2 = 0.98) suggesting that the primary effect of N deficits was reduced light interception because of smaller LAI. This analysis suggests, therefore, that the ratio BOLL/CA can be used to index boll shedding fraction in cotton and, with some estimate of CA based on expected yields or LAI, may have value as an input for cotton crop management.
Development and Maturation of White Lupine Seed
Authors: Clapham William M. , Barnes Sarah L. 
Published: July 2010

AbstractUnreliable ripening has limited production of white lupine (Lupinus albus L.) in northern temperate climates. Currently, there are no adequate methods to predict physiological maturity of this crop. The objectives of this study were to develop a descriptive index of maturation for white lupine pods and seeds, and to relate physiological maturity to the relationship between seed and pod moisture contents. Field data from a series of studies on the effects of planting date and plant density on white lupine growth and yield were used to generate the developmental index. The index was useful in determining developmental stages for both main‐stem and higher‐order lateral pods. Funicula detachment occurred between 55 and 80 kg kg−1 pod moisture content and was consistent with literature reports of physiological maturity, maturation drying and onset of desiccation‐tolerance. Rapid seed filling occurred when pod moisture content was greater than 83 kg kg−1 fresh weight. The relationship between pod and seed moisture content was linear and varied between years, but did not vary between main‐stem and lateral pods within year. At pod moisture content less than 83 kg kg−1, however, the relationship was curvilinear and did not vary over year or pod order (main‐stem or first‐order lateral pods). The change in slope of this relationship at 83 kg kg−1 pod moisture content may explicitly identify physiological maturity and the onset of maturation drying. Although lupine is harvested when seed moisture content falls below 20 kg kg−1, these data concur with reports in the literature suggesting that a lupine crop may be harvested when pod moisture content range from 55 to 80 kg kg−1 without loss of seed yield or viability.
Wind Profile Parameter Estimation Using Mathcad
Authors: Howell Terry A. 
Published: July 2010

AbstractWind profile parameters are required to estimate aerodynamic boundary layer resistances for heat, water vapor, and momentum transfer. Traditional methods used to compute these parameters take time to program, are slow to reach solutions, and often fail to achieve solution convergence. This study evaluated the applicability of a commercial mathematics software package, MathCAD, to estimate the three parameters—friction velocity (U*), zero‐plane displacement height (4, and the roughness length, Zo—of the adiabatic log‐law wind profile. The solutions were evaluated and compared to previous published solutions for several wind profiles using traditional methods. MathCAD was found to solve the wind profiles rapidly without convergence difficulty on the tested profiles. In all the comparisons, MathCAD produced almost exact duplications of previously published results. The ease, speed, and accuracy of the solution method employed in MathCAD appear to be superior to the more traditional methods.
Selenomethionine Uptake by Wheat Seedlings
Authors: Abrams M. M. , Shennan C. , Zasoski R. J. , Burau R. G. 
Published: July 2010

AbstractSelenium acquisition by crops is of interest because it is an essential element for higher animals and because excessive levels are toxic to humans and livestock. This research was conducted to test whether uptake by plants of an important organic Se compound, selenomethionine, occurred through a metabolically active process. Selenomethionine absorption in 30‐d‐old wheat (Triticum aestivum L.) seedlings was measured by using a depletion method with two initial nutrient solution concentrations (0.5 and 1.0 μM) selenomethionine. Observed uptake rates were functions of solution concentration and were not affected by initial concentration. Uptake kinetics appeared to conform to the Michaelis‐Menten function but the initial concentrations were too low to estimate either Km or Vmax (maximum uptake rate when carrier or permease is saturated). Selenomethionine uptake was inhibited by a metabolic inhibitor, 2,4‐dinitrophenol, and by anaerobic conditions. Absorption resumed when aerobic conditions were restored to the anaerobic treatment. Experimental evidence shows that wheat seedlings can acquire the biologically important organic Se compound, selenomethionine. This acquisition is under metabolic control which further suggests that organic forms of Se must be considered as sources of plant available Se.
Barley Treated with Ethephon: III. Kernels per Spike and Kernel Mass
Authors: Moss J. , Stobbe E. H. 
Published: July 2010

AbstractTreatment of barley (Hordeum vulgare L.) with ethephon [2‐chloroethyl)phosphonic acid)] may reduce lodging and increase kernel mass, but reductions in kernel mass and kernels per spike also are often observed. This study examined the effect of ethephon on kernels per spike and kernel mass for spikes on specific shoots which appeared before or after ethephon application. Ethephon was applied at Zadoks growth stage (GS) 35 and/or 45 at 240 g ha−1 to ‘Argyle’ conventional height and ‘Samson’ semidwarf barley grown at 100 and 300 plants m−2 at Winnipeg, MB. Tillers were tagged as they emerged on 10 plants per plot, and kernels per spike and kernel mass were determined for each spike produced. The cultivars did not differ in their response to ethephon. Kernels per spike was reduced as much as 26% by ethephon application. Such reductions were attributed to both the promotion of late‐appearing shoots with relatively few kernels, and the abortion of florets on main stems and early appearing tillers, which may be due to ethephon's gametocidal properties. Kernel mass was reduced by up to 17%, not affected, and increased by up to 12% by ethephon in 1987, 1988, and 1989, respectively. Differences in competition between developing kernels and late tillers, in lodging, and in nitrogen availability may account for the variable kernel mass responses observed. Kernels per spike and/or kernel mass reductions generally resulted in decreased yield per plant, especially for barley grown at 300 plants m−2, but such reductions were at least partially compensated by increased spikes per plant for barley grown at 100 plants m−2 in 1987 and 1989.
Yield Components in Three Meadowfoam Lines
Authors: Fiez Timothy E. , Norberg O. Steven , Jolliff Gary D. 
Published: July 2010

AbstractFuture development of high‐yielding meadowfoam (Limnanthes R. Br. spp.) cultivars may be enhanced if relationships between oil yield, yield components, and agronomical, phenological, and morphological traits can be established. To identify such relationships, two half‐sib L. floccosa Howell ssp. grandiflora Arroyo × L. alba Hartw. ex Benth. ssp. alba lines, ORL85‐765 and ORL85‐729, and ‘Mermaid’ meadowfoam were grown and compared in solid stand in 1987–1988 and 1988–1989 at the Oregon State University Schmidt Farm. Line 85‐765 produced the greatest oil yield in 1987–1988. Seed weight of line 85‐765 was 18 and 13% greater (P < 0.05) than lines 85‐729 and Mermaid, respectively, in 1987–1988. In 1988–1989, both lines 85‐765 and Mermaid produced greater oil yields than line 85‐729. Line 85‐765 produced a 7% greater seed weight and Mermaid produced 55% more seeds per flower than line 85‐729 (P < 0.05). Oil yields of lines 85‐765 and Mermaid were not significantly different in 1988–1989. Seed weight of line 85‐765 was 9% greater than Mermaid in 1988–1989, but Mermaid produced 31% more seeds per flower than line 85‐765 (P < 0.05). Seed weight differences were apparently due to variation in seed growth rate and not seed growth duration. Differences in seeds per flower were not related to pollinator activity or flower phenology. Both seed weight and seed number per flower were important yield components for determining the relative oil‐yield performance of lines 85‐765, 85‐729, and Mermaid.
Bulk Surface Resistance and Its Effect on Evapotranspiration Rates in Irrigated Wheat
Authors: Luchiari A. , Riha S. J. 
Published: July 2010

AbstractUse of the combination model to predict evapotranspiration (ET) from a crop has been limited by uncertainty in the value and behavior of the bulk sulface resistance (rb). The purpose of this study was to characterize rb for irrigated wheat (Triticum aestivum L.) and evaluate its use for predictive purposes. Hourly Bowen ratio measurements were made over a field of irrigated ‘Anahuac’ wheat during the entire growing season of 1983. Data from 4 d were used to calculate rb using both the energy balance and residual methods. Crop surface temperatures predicted from measurement of wind speed and air temperature at one height above the canopy were within 0.4 °C of infrared measured canopy temperatures. Both the energy balance and residual methods gave similar values for rb. From 0830 h to 1430 h the day before irrigation, values for rb ranged from 50 to 100 s m−1 whereas after irrigation, rb for the same period ranged from 15 to 50 s m−1. In both cases, rb rapidly increased after 1430 h to values above 200 s m−1 by 1630 h. At the same time, latent heat loss in proportion to net radiation increased and canopy temperature decreased more rapidly than air temperature, suggesting that the increase in rb at this time is not due to a lag in the supply of water to the canopy. The combination model was used to predict ET on both an hourly and daily basis for several periods during another crop growing season. Mean predicted values were within 6% of Bowen ratio measurements and were highly correlated with hourly and daily measured rates of ET, suggesting that the combination model can be used for predictive purposes when rb is well characterized.
Value of Selection for Osmotic Potential in Tropical Maize
Authors: Bolaños J. , Edmeades G. O. 
Published: July 2010

AbstractOsmotic adjustment, the lowering of osmotic potential (ΨS) under drought, is considered a desirable component of drought tolerance since it has been shown to maintain turgor, growth, and photosynthesis at lower water potentials. This study attemped to determine the relative merits of selecting for osmotic adjustment and low ΨS under drought in lowland tropical maize (Zea mays L.). During 3 yr of trials in Mexico that examined 204 maize landacres, elite open pollinated populations (OPPs), experimental synthetics (ESs), and hybrids, osmotic adjustment averaged 0.10 MPa and ranged from 0.54 to −0.23 MPa. Only 7% of genotypes showed a capacity to adjust by more than 0.40 MPa, a level considered minimum for them to serve as sources for the trait. Variation for ΨS, under drought for 222 to 225 S1 progeny of three maize populations ranged from −1.04 to −1.79 MPa. Divergent selection within each population for high and low ΨS under drought resulted in the formation of ESs which differed in ΨS by an average of 0.17 MPa when grown under a line source moisture gradient. Realized heritability for ΨS averaged 0.46. The ESs selected for high and low ΨS did not yield differently from the cycle bulk, suggesting little adaptive value for ΨS Correlations between several traits indicative of performance under drought and osmotic adjustment or ΨS under drought generally were weak, inconsistent, and non‐significant. These studies suggest that selecting for increased capacity to adjust osmotically or low ΨS under drought does not appear advantageous in lowland tropical maize.