bluuebunny/crossref_metadata_2025_split huggingface dataset:
Relating Sugar Fluxes during Bale Storage to Quality Changes in Alfalfa Hay
Authors: Coblentz Wayne K. , Fritz John O. , Bolsen Keith K. , Cochran Robert C. , Fu Lin‐qian 
Published: July 2010

AbstractNegative quality changes that occur when alfalfa (Medicago sativa L.) is baled at moisture levels in excess of 200 g kg−1 have been well documented; however, relatively little is known about changes in nonstructural carbohydrate pools during bale storage and how these changes are involved in depression of forage quality. The objectives of this study were to quantify nonstructural carbohydrate pools at specific time periods during bale storage and to relate these findings to accumulated heating degree days and traditional quality indices. Alfalfa forage was field‐dried to high‐ and low‐moisture concentrations of 299 and 197 g kg−1, respectively, and packaged as conventional (CONV) and laboratory‐scale (LAB) bales. During the first 4 d of storage, reducing sugar concentrations appeared to increase in highmoisture conventional bales and high‐moisture laboratory bales made at twice the density of conventional bales (treatments that most favored spontaneous heating). Between 4 and 11 d in storage, reducing sugar concentrations for these treatments decreased sharply and continued a gradual decline thereafter, effectively mirroring the concurrent increases in acid‐detergent insoluble N (ADIN). Nonreducing free sugar, total free sugar, and total nonstructural carbohydrate (TNC) concentrations declined rapidly during storage; these responses were linearly related to increases in heating degree days >30°C. For high‐moisture treatments, ADIN concentrations were strongly correlated with total free sugar and TNC levels (r = −0.90 and −0.90, respectively). Correlations between ADIN concentrations and reducing sugars (r ≤ −0.72) appeared weaker. At the low moisture level, reducing sugar concentration was not related (P ≥ 0.05) to ADIN concentration.
Symbiosis with Neotyphodium uncinatum Endophyte May Increase the Competitive Ability of Meadow Fescue
Authors: Malinowski D. , Leuchtmann A. , Schmidt D. , Nösberger J. 
Published: July 2010

AbstractInfection with the endophyte Neotyphodium uncinatum (Gams, Petrini & Schmidt) Glenn, Bacon, Price & Hanlin may influence drought resistance and competitive ability of meadow fescue (Festuca pratensis Huds.). We determined endophyte‐related effects on some growth and physiological characteristics in one clone of meadow fescue. In a growth chamber experiment, meadow fescue and orchardgrass (Dactylis glomerata L.) were planted in pots as monocultures or binary mixtures, competing in the root systems. One group of plants was adequately watered to maintain the original pot weight (control). The other group was subjected to a gradually imposed water stress, defined as soil water deficit, during 25 d (stressed plants). After rewatering, plants were allowed to regrow for 3 wk. Endophyte infection increased shoot and root dry weight by 33 and 70%, respectively, in control meadow fescue plants, and by 24 and 69% in stressed plants. Infected (E +) plants had significantly greater competitive ability than noninfected (E−) plants when grown in E−/E+ binary mixture. In binary mixtures with orchardgrass, the competitive abilities of E− and E+ plants were reduced relative to that of E− and E+ plants grown as monocultures. In response to water stress, stomatal conductance was lower in E+ than in E− plants, regardless of root competition. Noninfected plants could not completely recover in leaf water potential when exposed to root competition with infected plants or orchardgrass. The greater competitive ability of E+ plants was related to improved root and shoot growth and enhanced drought resistance. Infection with N. uncinatum could confer a competitive advantage to the meadow fescue clone.
Recovering Information in Augmented Designs, Using SAS PROC GLM and PROC Mixed
Authors: Wolfinger Russell , Federer Walter T. , Cordero‐Brana Olga 
Published: July 2010

AbstractThe SAS GLM and MIXED procedures can be useful for experimenters desiring to analyze data from screening experiments using a member of the class of augmented experiment designs. Since application of the procedures is typically not straightforward for these designs, several programs of possible interest are described. We show how to recover interblocking and intervariety information when the blocking and varieties are random effects, how to arrange varietal responses in descending order, and a number of other options.
Tillage Effect on Soil Water Content and Corn Yield in a Strip Intercropping System
Authors: Ghaffarzadeh Mohammadreza , Préchac Fernando García , Cruse Richard M. 
Published: July 2010

AbstractA three‐crop strip intercropping system including corn (Zea mays L.), soybean [Glycine max (L.) Merr.], and oat (Avena sativa L.) interseeded with nondormant alfalfa (Medicago sativa L.), was established in south‐central Iowa on a poorly drained Haig soil (fine, smectitic, mesic Vertic Argiaquoll). In 1989 (a dry year) and 1990 (a wet year), we studied the effect of tillage treatment (conventional, CT; reduced, RT; and no‐till, NT) and row position on soil water content, canopy and air temperatures, corn grain yield, and yield components. No‐till resulted in the most favorable soil water status, plant water status, and grain yield in 1989. No‐till had the poorest performance in 1990, mainly because of excessive soil water. The opposite was true for conventional till in both years. Reduced till yield equaled that for the most productive tillage treatment in both years. Conventional and reduced tillage resulted in lower corn grain yield at the border with oat‐alfalfa than with soybean because oat depleted soil water more than soybean in both years. In contrast, for no‐till the corn grain yield at the border with oat‐alfalfa was 6% greater than corn yield bordering soybean in 1989 and 13% greater in 1990. When water was not limiting, in 1990, both corn borders outyielded the center rows by an average of 14% in NT, 27% in RT, and 28% in CT. Soil water content rankings throughout the 1989 season were NT > RT > CT and row position rankings were soybean border > center > oats‐alfalfa border. In 1990, there were no soil water content differences between tillage treatments and row positions. Reduced tillage is the most suitable soil management system for corn production with three‐crop strip intercropping on this soil, considering consistently high relative yields for both wet and dry years.
Influence of Seeding Rate on Big Bluestem Establishment with Herbicides
Authors: Masters Robert A. 
Published: July 2010

AbstractWeeds interfere with establishment of big bluestem (Andropogon gerardii Vitman var. gerardii Vitman) on rangeland and cropland in the central Great Plains of North America. A study was conducted to determine the influence of seeding rate on establishment of big bluestem when metolachlor [2‐chloro‐N‐(2‐ethyl‐6‐methylphenyl)‐N‐(2‐methoxy‐1‐methylethyl)acetamide] and atrazine [6‐chloro‐N‐ethyl‐N′‐(1‐methylethyl)‐1,3,5‐triazine‐2,4‐diamine] were applied alone or in combination. ‘Pawnee’ big bluestem was planted in late May to early June 1990 and 1991 near Clay Center and Mead, NE, at 110, 220, and 440 pure live seed (PLS) m−2. Metolachlor at 0, 2.2 or 3.3 kg a.i. ha−1 and atrazine at 2.2 kg a.i. ha−1 were applied alone or in combination before weeds or the seeded big bluestem emerged. Big bluestem stand frequency (the number of times the planted grasses occurred within sampling grids and expressed as a percentage of the total number of grids evaluated) and yield were measured the year after planting to determine establishment success. Big bluestem stand frequency and yield were influenced primarily by the main effects of herbicide and seeding rate. Grass stand frequencies usually increased with increasing seeding rate. Big bluestem stands were successfully established in three of the four environments evaluated when seeded at 110 PLS m−2, and in all environments when seeded at 220 or 440 PLS m−2. Big bluestem yields were at least 1.2 Mg ha−2 greater on areas treated with metolachlor than on areas not so treated at Clay Center in 1991 and 1992 and Mead in 1991. Atrazine increased big bluestem yields by 1.2 and 2.4 Mg ha−1 at Mead in 1991 and 1992, but had no effect on yields at Clay Center. Based on these findings, metolachlor and/or atrazine can be applied preemergence the year of planting to improve yield of big bluestem seeded at a rate as low as 110 PLS m−2.
Modeling Soybean Cultivar Development Rates, Using Field Data from the Mississippi Valley
Authors: Acock Basil , Pachepsky Yakov A. , Acock Mary C. , Reddy Vangimalla R. , Whisler Frank D. 
Published: July 2010

AbstractTo predict how crop yields of soybean [Glycine max (L.) Merr.] respond to management practices, we need a reliable understanding of how environmental factors affect ontogeny of the many soybean cultivars grown. The objective of this work was to use field observations to develop equations relating reproductive development to environmental variables for several cultivars grown commercially in the southern USA. We used data on five soybean cultivars, recorded during farm testing of the soybean crop model GLYCIM in 1993, 1994, and 1995. Crop development stages were determined by averaging the Fehr and Caviness development stages of individual plants. We inspected the data and found that it could be fitted using a piecewise linear regression with alternating horizontal and sloping segments. The progress in crop reproductive development stages was expressed as a function of time after emergence for the period before flowering, and as a function of thermal time for the period after flowering. Horizontal segments that occurred near R2, R5, and R6 were interpreted as developmental plateaus (i.e., a period when the crop remains at a given stage). The length of the R2 plateau was a function of date of emergence, and the length of the R6 plateau was a linear function of soil surface water balance. In our dataset, there was no effect of soil properties, irrigation, or plant population density on reproductive development. The technique developed in this study will facilitate the application of crop simulation models on farms by providing a way to develop a set of parameters for reproductive development for any cultivar being grown.
Accumulation of Dry Matter and Evolution of Nutritive Value in Serradella (Ornithopus sativus Brot.)
Authors: Lloveras Jaime , Iglesias Isabel 
Published: July 2010

AbstractDevelopment of efficient forage management and utilization is facilitated by knowledge of nutrititive value evolution and dry matter (DM) distribution patterns within plants. The objectives of this experiment were to determine the patterns of DM accumulation and the evolution of nutritive value from the vegetative stage to the ripe seed stage of serradella (Ornithopus sativus Brot.), a cool‐season annual forage legume adapted to acid soils. Serradella was established on a Dystric Eutrochrept soil with pH 5.4 in Mabegondo, northwestern Spain, for three consecutive years (1990–1992). Shoot samples were taken at approximately biweekly intervals in the spring and summer following autumn seeding, and were separated into stems, leaves, and seed pods. Dry matter (DM) accumulation, crude protein (CP), aciddetergent fiber (ADF), and in vitro organic matter digestibility (IVOMD) were determined for each plant part at each stage. Average annual DM production at initial flowering was 5.1 Mg ha−1, and the CP, ADF, and IVOMD concentrations were 163, 279, and 750 g kg−1, respectively. The rates of nutritive value decline with age coincided with a reduction in leaf‐to‐stem ratio (from a range of 1.91 to 2.85 at vegetative stage to 0.2 at ripe seed stage) and appear lower than the rates reported for other legumes, possibly because of the long indeterminate flowering period. We concluded that the nutritive value parameters of serradella indicate that this legume has a forage quality comparable to other leguminous crops and, if seeded in double‐cropping systems (as is done in some Atlantic coastal areas of southern Europe, where it is harvested around initial flowering), it can provide forage of good quality.
Potassium Effects on Canopy Light Interception and Earliness of No‐Tillage Cotton
Authors: Gwathmey C. Owen , Howard Donald D. 
Published: July 2010

AbstractEarliness of maturity is essential for adaptation of cotton (Gossypium hirsutum L.) to regions with short growing seasons, and it may be influenced by potassium nutrition. Our objectives were to determine effects of K fertilization on interception of photosynthetically active radiation and earliness, and to describe the relationship between earliness and light interception at different in‐canopy heights. Research was conducted with no tillage on a Memphis silt loam (fine‐silty, mixed, active, thermic Typic Hapludalf) with low extractable K. Using a split‐plot randomized complete block design, 0 and 112 kg K ha−1 were soil‐applied before planting each year as mainplot treatments, and 0 and 4.1 kg K ha−1 were foliar applied four times per season as subplot treatments. Canopy interception of photosynthetic photon flux density (PPFD) was measured at 23‐cm vertical increments in 1993 and 1994. Plots were spindle‐picked twice each year. Earliness was measured as the percent of total yield picked at first harvest. Relative to no fertilizer K, soil‐applied K increased canopy PPFD interception at all heights measured. Neither soil‐applied nor foliar K affected earliness in 1993, a drought year, but soil‐applied K decreased percent first harvest from 78 to 65% in 1994. Foliar K did not affect canopy light interception in 1993, and it increased interception in 1994 only with no soil‐applied K. At 111 d after planting, percent first harvest was negatively correlated with PPFD interception at all measured heights in the canopy, suggesting that higher K fertility delayed maturity as it increased upper‐canopy light interception. In short‐season environments, optimum K fertilization needs to be accompanied by cultivar selection and management that promote earliness of maturity.
Grain Amaranth Seeding Dates in the Northern Great Plains
Authors: Henderson Tracey L. , Johnson Burton L. , Schneiter Albert A. 
Published: July 2010

AbstractAn understanding of crop response to planting date is essential when evaluating a potential new crop. A field study was designed to determine the optimum range of planting dates for dryland grain amaranth (Amaranthus cruentus L. and A. hypochondriacus L. ✕ A. hybridus L.) in the Northern Great Plains. Four grain amaranth cultivars, diverse for plant height and branching, were evaluated over four consecutive years from 1989 to 1992 at Prosper (46°58′ N, 97°4′ W, elevation 220 m) in North Dakota. Soil types at the test site are a complex of Perella (fine‐silty, mixed, superactive, frigid Typic Endoaquolls) and Beardon (fine‐silty, mixed, superactive, frigid Aeric Calciaquolls). Four or five planting dates were selected, ranging from 1 May to 1 July at approximately 15‐d intervals. Year‐to‐year differences in weather influenced the response of amaranth to planting date for grain yield, days to anthesis, harvest index, plant height, final plant population, and lodging. Plants sown in mid‐June produced the greatest grain yield in 1989 and 1990, when near‐ or above‐average temperatures occurred throughout most of the growing season. Seedling survival was greater with later planting dates in all years except 1989, when excellent stands were achieved with all planting dates. Greatest yields in 1992, an unusually cool year, were produced with May planting dates; in that year, most plants sown in mid‐June did not mature before first frost. Material planted on 1 July failed to mature in both 1991 and 1992. In years with near‐ or above‐average temperatures, the mid‐June planting date was best for maximizing both stand establishment and grain yield. Given the uncertainty in predicting weather conditions, planting in early June in the Northern Great Plains should achieve good stands and produce high grain yields, while minimizing the risk of yield loss associated with cool condition.
Extractable Soil Water and Transpiration Rate of Soybean on Sandy Soils
Authors: Sinclair Thomas R. , Hammond Luther C. , Harrison J. 
Published: July 2010

AbstractSubstantial consistency has been obtained in describing plant response to drying soil by expressing plant performance as a function of the fraction of soil water that can be used by the plants. Generally, there is no decrease in plant activity until the soil water has been decreased to the level where only about 0.3 of the water that can be extracted by the plants remains in the soil. There is, however, ambiguity as to whether this relationship is appropriate for sandy soils. The objective of this research was to compare methods for describing extractable soil water by soybean [Glycine max (L.) Merr.] plants grown in pots with soils differing in sand content. The two methods tested were based on thermodynamic and physiological definitions of the upper and lower end‐points of extractable soil water. While differences existed in the volumetric soil water content for the two definitions of the lower end‐point of extractable soil water, these differences were small. In contrast, very large differences existed in defining the volumetric soil water of the upper end‐point either thermodynamically (commonly assumed to be ‐10 kPa for sands) or physiologically (pot capacity). As a consequence, there were large differences in the response curves obtained based on the two expressions of extractable soil water. The threshold for transpiration expressed as an absolute volumetric soil water was of course independent of the determination of the end‐points. Instead of relying on a relative transpiration response to extractable soil water, for sandy soils it may be necessary to use the volumetric soil water content determined under controlled conditions to interpret crop response under any particular field situation.
Testing for Early Photoperiod Insensitivity in Soybean
Authors: Wang Zhongchun , Reddy Vangimalla R. , Acock Mary C. 
Published: July 2010

AbstractTo accurately model the flowering process in soybean, it is essential to identify photoperiod‐sensitive and photoperiod‐insensitive phases of development. Despite extensive studies, there remains some disagreement about when soybean plants first become sensitive to photoperiod. The length of the juvenile phase from emergence has been found to differ for the same cultivar. This experiment tested the hypothesis that the early phase in soybean development is truly photoperiod‐independent. Soybean plants [Glycine max (L.) Merr. cv. Hutcheson; Maturity Group V] grown in controlled environments at a constant air temperature of 26°C were transferred from a noninductive 22‐h photoperiod to an inductive 8‐, 10‐, 12‐, or 14‐h photoperiod at 2‐ to 5‐d intervals after seedling emergence (defined as the day when the cotyledons appeared above the soil surface). The duration of the so‐called juvenile phase was shown to be photoperiod‐dependent, the photoperiod effect being nonlinear. Soybean plants became sensitive to an 8‐, 10‐, 12‐, and 14‐h photoperiod at ‐1, 0, 1, and 9 d after seedling emergence, respectively. Based on these and other results, we conclude that there is no juvenile phase in Hutcheson soybean, and that photoperiod sensitivity begins when seedlings are exposed to light, but the rate of progress towards flowering depends on the photoperiod experienced.
Soybean Seed Coat Discoloration in Cool‐Season Climates
Authors: Morrison Malcolm J. , Pietrzak Lukasz N. , Voldeng Harvey D. 
Published: July 2010

AbstractSoybean [Glycine max (L.) Merr.] seed with yellow seed coat and hilum is preferred in North America for the export market. Seed coats may darken or discolor when exposed to chilling temperatures during seed development. We examined the effects of chilling temperatures on seed coat discoloration of yellow hilum, isogenic lines of ‘Maple Presto’ soybean (Maturity Group 000) differing in pubescence color (I, r, T, tawny; I, r, t, gray). The isogenic lines were grown in the field for five seasons and once in the growth cabinet (25/20°C day/night). We quantified seed coat discoloration using an image analyzer. When exposed to cool temperatures during seed development, the seed coat darkened. In the extreme case, the seed coat from the tawny line looked gray‐brown. The tawny line discolored more than the gray line, both in the field and the growth cabinet. Seed coat discoloration increased with the accumulation of daily minimum temperature ≤ 115°C during seed development. In years with cool temperatures during seed development, seed coats may discolor, reducing the quality of the seed's appearance.
Nitrogen Fertilizer Effect on Grain Amaranth
Authors: Myers Robert L. 
Published: July 2010

AbstractGrain amaranth (Amaranthus spp.) is an ancient crop that is now receiving fresh attention. This has led to a demand for crop management information, including that on N fertilization. This study evaluated the effect of N fertilizer on amaranth grain yield, yield components, and growth and development. The study was carried out in three Missouri environments with five levels of N fertilizer (NH4NO3 broadcast preplant at 0, 45, 90, 135, and 180 kg N ha−1) and three cultivars (Plainsman, D136, and K266). Averaged across cultivars and environments, N fertilizer at the top rate of 180 kg N ha−1 produced a yield increase of 42% relative to plots receiving no N fertilizer. Yields were consistently improved by additions of 45 and 90 kg N ha−1, but additional N fertilizer above the 90 kg N ha−1 rate increased yield in only one out of three environments. At the one site where yield components were evaluated, yield differences were due to increases in seed number per plant, since seed weight and plant population at maturity were unaffected by N fertilizer rate. Plots with high rates of N fertilizer had later maturity, as indicated by time of flowering and seed moisture. Average moisture of seeds harvested from plots receiving 180 kg N ha−1 was 320 g kg−1, while seeds from plots with no N fertilizer had 240 g kg−1 moisture. Comparing the same high‐N treatment to the control with no N showed height increases of 14, 24, and 44% in the three environments. Although amaranth yield is responsive to N fertilization, high rates of N fertilization can negatively affect grain harvest in terms of excessive plant height, increased lodging, and delayed crop maturity.