bluuebunny/crossref_metadata_2025_split huggingface dataset:
Soybean Plant Response to Temporary Field Windbreaks1
Authors: Radke J. K. , Burrows W. C. 
Published: July 2010

AbstractSmall temporary windbreaks consisting of corn rows or snowfence were spaced at various intervals in soybean fields in western Minnesota. Data from 11 location‐years showed that soybeans sheltered by temporary corn windbreaks grew taller, produced more dry weight, had a larger leaf area index, and produced higher grain yields. Soybean rows adjacent to corn windbreaks did not do as well as the rest of the windbreak‐sheltered soybeans because of shading effects and root competition from the corn. There was no statistical difference in wateruse; however, water‐use efficiency was increased due to higher soybean yields. Results obtained with snow‐fence windbreaks were similar, but to a lesser extent than those obtained with corn windbreaks.Windbreaks oriented in an east‐west direction were more effective than windbreaks oriented in a northsouth direction since the prevailing summer winds in western Minnesota are south to southeasterly. Windbreak spacings between 6 H and 15 H (H = height of windbreak) were effective, and it is possible that windbreaks spacings greater than 15 H would be effective.
Influence of Temperature, Light Intensity, and Aeration on Growth and Root Porosity of Wheat, Triticum aestivum1
Authors: Varade S. B. , Stolzy L. H. , Letey J. 
Published: July 2010

SynopsisInfluence of three energy levels and two oxygen concentrations on the growth and root porosity of. ‘Sonora 64’ and ‘Naineri’ wheats was studied in an environmental control chamber. Energy levels included three temperatures and three light intensities.The dry weights of shoot and root, volume of roots, and number of tillers were adversely affected by low oxygen supply and low energy input. Increased root porosity under low O2 supply suggests that gas space development in wheat is closely related to anaerosis. An increase in gas space development occurred under conditions of higher rates of growth. When temperatures were high, low oxygen supply was more detrimental to shoot and root growth.Optimum temperature was 25 C for both varieties, although Naineri variety was more responsive to temperature and light intensity. Amounts of water consumed was higher when high temperature and light intensity prevailed. Water use was higher under low oxygen supply than under well‐aerated plants. Water use also appears to be related to gas space in roots.
Effects of Plant Population on Castorbean Yield1
Authors: Kittock D. L. , Williams J. H. 
Published: July 2010

AbstractPlant population effects on yield and growth of irrigated and non‐irrigated castorbeans (Ricinus communis L.) was tested for 3 years. The optimum plant population of irrigated dwarf‐internode castorbeans was about 58,000 plants per ha. Row spacings from 0.5 m to 1.0 m did not significantly affect yields, if plant population was held constant. The optimum plant population for nonirrigated castorbeans was near or higher than the highest population in our tests. It was clearly higher than the current recommendation of 20,000 plants per ha. Linear regression of yield on plant population was significantly different among cultivars and among tests for the nonirrigated castorbeans. Cultivars with bushy growth and small racemes had greater yield depression from low populations than did more erect cultivars with large racemes. Plant population effect on yield was reduced as the yield level of the nonirrigated tests decreased.Low plant population in nonirrigated tests increased plant height, hypocotyl diameter, length of primary raceme, number of racemes per sequential set, and yield of all sets of racemes. Low population reduced height of the primary raceme from the soil. Population had no effect on nodes to the primary raceme. Oil content of the seed or test weight were not affected by plant population of nonirrigated castorbeans.
Rooting System of Soybeans. II. Physiological Effectiveness as Nutrient Absorption Surfaces1
Authors: Raper C. D. , Barber S. A. 
Published: July 2010

Abstract‘Aoda’ and ‘Harosoy 63’ soybeans [Glycine max (L.) Merr.], representing extremes in gross root morphology, were used in field and growth chamber experiments to study the influence of physiological characteristics of soybean roots on the absorption of nutrients. The efficiency of K uptake per unit root surface was found to be dependent on the variety and the solution concentration of K. The rate of K uptake per unit root surface, or K absorption potential, for Aoda roots was almost double that of Harosoy 63 roots at high levels of K but was nearly equal at low levels. The effect of K concentration on absorption potentials in nutrient solution was independent of concurrent variation of other nutrientions or total growth rate of the plants.
Forms of Nitrogen and Nitrogen Availability in Fescuegrass Sod1
Authors: Giddens Joel , Hauck R. D. , Adams W. E. , Dawson R. N. 
Published: July 2010

AbstractOrganic N fractions and 15N uptake by sudax (Sorghum vulgare), a sudan × sorghum hybrid, were determined in soils that had been in fescuegrass (Festuca arundinaceae) 0 through 5 years and in soils that had been taken out of fescuegrass 0 through 5 years.Percentages of N in the distillable acid‐soluble, nondistillable acid‐soluble (amino acid N), and nonacidsoluble fractions did not change appreciably. Total N increased with age of sod and decreased with length of time sod had been plowed into the soil. Soil N content had no significant effect on the uptake of 15N‐labeled NH4Cl applied at a single N rate. The nitrogen percentage taken up by sudax from the soil, however, increased as the soil nitrogen increased.
Effect of N Fertilizer on Yield, Crude Protein Content, and in vitro Dry‐Matter Disappearance in Phalaris arundinacea L.1
Authors: Niehaus Merle H. 
Published: July 2010

Abstract‘Ioreed,’ ‘Frontier,’ and ‘Common,’ three cultivars of reed canarygrass, Phalaris arundinacea L., each grown at four rates of N, were evaluated for dry‐matter yield, percentage of crude protein, and in vitro dry‐matter disappearance (IVDMD). Nitrogen was applied at 75, 150, 300, and 600 kg/ha/yr. There was a large increase in dry‐matter yield and percentage of crude protein in response to increased N fertilizer, but IVDMD was not affected by N rate. Differences between cultivars were small for all traits. Interactions between N rates and cultivars involving dry‐matter yield existed but did not change the ranking of cultivars.
Inoculum Rate and Pelleting of Arrowleaf Clover Seed1
Authors: Wade R. H. , Hoveland C. S. , Hiltbold A. E. 
Published: July 2010

AbstractPoor nodulation and low winter forage production often result when arrowleaf clover (Trifolium vesiculosum Savi) is seeded for the first time. Indigenous rhizobia in the soil may be more competitive than the normally limited number of seed‐applied rhizobia. Field and growth chamber experiments were carried out to determine the effects of inoculum rate and seed pelleting on nodulation and yield of arrowleaf clover in soils with intact microbial populations and where modified by soil fumigation.Doubling the inoculum rate, CaCO3 pelleting, or soil fumigation increased annual dry forage yields 1,200 to 2,000 kg/ha over that of the normal rate of inoculum. These treatments improved both nodulation and seedling growth. Winter forage yields were increased 200% by pelleting inoculated seeds with CaCO3. Seed pelleting was beneficial in nonfumigated soil, but not in fumigated soil, suggesting that pelleting made conditions more favorable for seed‐borne rhizobia to compete with native soil microorganisms. The presently recommended rate and method of application of inoculum are not satisfactory for rapid nodulation and maximum winter forage production of arrowleaf clover. Increasing the inoculum rate or pelleting the inoculated seeds should result in rapid nodulation and furnish more whiter forage.
Productivity and Forage Quality of Yuchi Arrowleaf Clover1
Authors: Hoveland C. S. , McCormick R. F. , Anthony W. B. 
Published: July 2010

AbstractPoor recovery growth after cutting in spring has been a problem with ‘Yuchi’ arrowleaf clover (Trifolium vesiculosum Savi). This research was conducted to study the effect of cutting management on persistence, forage yield, and quality of this winter annual clover.In field studies at two locations for 2 years, late spring clover recovery and forage production were dependent on cutting dates and height of plants when cut. Cutting at hay stage in late April or May eliminated stands and aftermath growth while cutting biweekly maintained stands although yields were reduced. Root carbohydrate levels declined during spring but were not related to cutting; treatment. A low number of buds at the base of the clover plants resulted in poor regrowth of forage. After early April, clover allowed to grow 60 to 90 cm tall before cutting had few buds at base of the plants. Maximum forage yields (7,300 kg/ha) were obtained by biweekly cutting until early April followed by a cutting of hay in late May.Digestible dry matter of forage was high, ranging from 80% in late winter to about 70% at early bloom stage in late May. Tannin content of forage ranged from 3 to 6% with leaves containing 2.5 times the tannin content of stems. This may account for the low incidence of bloat in cattle grazing this clover. Lysine content of the forage averaged 8.5% of the protein.
Effect of Planting Date on Water‐Use and Its Efficiency in Dryland Grain Sorghum1
Authors: Blum A. 
Published: July 2010

AbstractIt has been postulated that water regime was the major operative factor responsible for different yield response of dryland grain sorghum [Sorghum bicolor (L.) Moench] to different planting dates. Our research was done in order to appraise this postulation.For four consecutive years, four grain sorghum hybrids were planted on two planting dates (March 20–24 and April 12–16) in Israel under conditions of limited water supply as determined by the amount of stored soil moisture prior to planting. Vegetative development, grain yield, and soil water extraction profiles were determined.Early planting, as compared with late planting, increased grain yield through increased tillering and greater weight per grain. During the period from emergence to 51 days, early planted sorghum used about half as much water as late‐planted sorghum. Early planted sorghum was less water stressed, as evidenced by lower leaf diffusive resistance prior to heading and smaller reduction in LAI (leaf desiccation) after heading, as compared with late‐planted sorghum. Lower water use in early planted sorghum, during the period prior to heading, was ascribed to lower potential evapotranspiration, smaller LAI, and possibly slower root development, as compared with the respective period in late‐planted sorghum. Total amount of water used at maturity did not differ between planting dates, apparently due to the longer period of growth and the larger amount of stover dry matter per plant in early planted sorghum, which served to offset the decreased water use during the earlier phase of growth.No appreciable differences were found between hybrids tested in terms of adaption to early planting or water use.
Varietal Stability in Smooth Bromegrass (Bromus inermis Leyss.) as Affected by Regional Seed Production1
Authors: Knowles R. P. , Christie B. R. 
Published: July 2010

AbstractCertified seed lots of ‘Lincoln,’ ‘Saratoga,’ and ‘Fischer’ bromegrass (Bromus inermis Leyss.) produced in Western Canada were compared with original Breeder or Foundation seed from Nebraska, New York, and Iowa, respectively. Seed lots were used for production trials at Saskatoon, Saskatchewan (latitude 52°) and Guelph, Ontario (latitude 43°). The object was to find if southern‐bred varieties were modified through seed multiplication in a northern area.At Saskatoon there was no change (P = .05) in forage yields, height of growth, or seed volume weight for any variety. Significant differences in seed yields of lots of Lincoln and Saratoga were recorded. No pattern related to area of seed production was evident in Lincoln, but in Saratoga two of the four Certified lots yielded significantly less seed than Breeder and Foundation lots. At Guelph no significant change in forage yields was noted for Lincoln or Fischer. Two of four certified lots of Saratoga were significantly lower in forage yields than the Foundation lot but not below the Breeder lot. In vitro digestibility analyses of hay showed differences among varieties but good conformity for all samples within varieties. It was concluded that southern varieties of bromegrass could be multiplied in northern areas without serious alteration of forage potential providing there is limited generation increases.‘Carlton,’ a northern cultivar, showed no significant change in forage or seed yields as a result of two generations of seed production in various districts within Western Canada.
Leaf Area Index and Radiation as Related to Corn Yield1
Authors: Scarsbrook C. E. , Doss B. D. 
Published: July 2010

AbstractTwo corn (Zea mays L.) hybrids were grown in 1969 and 1970 under irrigation at populations of 20,000, 40,000, and 80,000 plants/ha and at 51 and 102 cm row widths.The purpose of the research was to determine the relationship of radiation and partial leaf area indices (LAI's) to corn yields. Radiation in the 350 to 450 nm range was measured at 0, 60, 120, and 180 cm above ground during four 3‐day radiation periods. LAI measurements were made once each year during the grain filling stage of growth. The coefficient of determination (R2 = .64) between grain yield and LAI of the 120‐ to 180‐cm segment was the highest of any 60 cm segment and was equal to the coefficient of determination between grain and the total LAI. The coefficient (R2 = .64) between stover yield and the 120 to 180 cm LAI was higher than that between stover yield and the total LAI (R2 = .56).There was a satisfactory fit of the data to a linear regression of grain yield on radiation measured either at 0 or 60 cm above ground. From 61 to 74% of the variation in grain yield was predicted by radiation measured at 0 or 60 cm heights.
Cell Wall Properties of Cotton Roots as Influenced by Calcium and Salinity1
Authors: Gerard C. J. , Hinojosa E. 
Published: July 2010

AbstractResearch was conducted to determine the influences of salinity and Ca uptake on cell wall properties of cotton (Gossypium hirsutum L.) roots. It was postulated that examination of cell wall properties might give insight on the role of Ca in moderating the influences of salinity and toxic ions on cellular stability and plant growth. Age and Ca are essential to the development of thick cell walls in the stele. Thick cell wails exhibit high birefringence under polarized light. Salinity reduced Ca uptake and concentration of cotton roots. Xylem and phloem cell walls of cotton roots grown in solutions with sufficient Ca and low salinity thickened and in about 70 hours, exhibited high birefringence. Young cell walls in the pericycle or laterals did not exhibit birefringence. Even at adequate level of Ca, salinity retarded the development of thick cell walls and high birefringence in the stele to about 140 hours. The time required to develop thick cell walls may determine cellular stability or breakdown. The birefringent properties of certain plant parts seem to offer opportunities to study cellular disorders in plants due to the stress conditions of Ca deficiency or salinity.
Effect of Nitrogen Source, Rate, and Timing on Growth and Carbohydrates of Merion Bluegrass1
Authors: Watschke T. L. , Waddington D. V. 
Published: July 2010

AbstractNitrogen fertility stimulates turfgrass growth and, therefore, reduces carbohydrates. Turfgrass response to stresses (heat, drought, and disease) is improved when carbohydrates are highest. This study was conducted to determine the effect of different nitrogen sources, rates, and time of application on the growth and soluble carbohydrate content of ‘Merion’ Kentucky bluegrass (Poa pratensis L.).During 1971 and 1972 Merion was fertilized with urea, Uramite (ureaformaldehyde), Milorganite (activated sewage sludge), IBDU (isobutylidine diurea), and Urex (extruded urea‐paraffin matrix) at different rates and application dates. Growth was measured weekly and total nonstructural carbohydrate content every 2 weeks. Growth stimulation from slow release sources reduced carbohydrates when temperatures were high; improved growth uniformity resulted from split applications of these materials. Urex stimulates early growth more than other slow release sources, resulting in a severe depletion of carbohydrates prior to warm weather. Multiple applications of Urea and Milorganite gave more uniform growth throughout. the season with less fluctuation of carbohydrates than other sources. Nitrogen fertility, moisture, and temperature, collectively, interacted with the metabolism of Merion, their effects being readily reflected in the total nonstructural carbohydrate content. Periodic cool spells during the season offset reductions in carbohydrates caused by nitrogen fertilization, regardless of the fertilizer source. However, prolonged warm spells occur along the southern boundary of cool‐season turfgrass adaptation, and we conclude these temperature stresses could have severe effects, particularly if the stresses coincide with nitrogen induced carbohydrate depletion.
Nitrogen Fixation by Soybeans as Influenced by Inoculum Placement: Greenhouse Studies1
Authors: Wilson D. O. 
Published: July 2010

AbstractMaximum summer surface soil temperatures in many areas greatly exceed the optimum temperature for symbiotic N fixation by legumes. Formation of nodules on roots deep in the soil may enhance N fixation because of reduced extremes in soil temperature and moisture. The purpose of the study was to determine whether nodule position could be controlled by inoculum placement and the effect of surface soil moisture on N fixation by such nodules.Soybeans (Glycine max (L.) Merr.) were grown in a greenhouse at Experiment, Georgia, in plastic pots containing preplaced rhizobial inoculum and 1.5 mg molybdenum at 15, 100, and 200 mm below the soil surface. High (90% field capacity) and low (air‐dry) surface soil moisture treatments were also included. Two experiments were conducted, one at moderate and the other at relatively high greenhouse temperatures (27 to 30 C and 37 to 41 C daily maxima, respectively). In all treatments, inoculation depth strongly influenced the pattern of nodule development with most of the nodular tissue forming on roots at or near the depth of inoculation. At moderate greenhouse temperatures, neither inoculation depth nor surface soil moisture affected the amount of N fixed. At relatively high greenhouse temperatures, plants in the low surface soil moisture treatments fixed less than 25% of the N fixed by those in the high surface soil moisture treatments at the 15 mm inoculation depth. A decrease in N fixation at the deeper inoculation depths was also observed at the higher greenhouse temperatures.
Dynamics of Rehydration in Leaf Disks1
Authors: Molz Fred J. , Truelove Bryan , Peterson Curt M. 
Published: July 2010

AbstractThe time course of rehydration by living tissue appears to occur in two distinct phases. Phase I is associated with passive recovery from a water deficit while phase II is associated with the resumption of growth‐related water uptake. However, experimental efforts have been unable to clearly separate the two water absorption mechanisms, and much controversy exists concerning when phase II begins, when phase I ends, and the relative contribution of each phase to the total water uptake. The latter is particularly important in relative turgidity determinations where phase II uptake leads to errors.In order to help answer some of the above questions it was decided to apply the water transport theory of Molz and Ikenberry to water uptake by floating leaf disks of sunflower (Helianthus annuus L.). The theory can be used to predict quantitatively the time course of phases I and II separately and together. From computer solutions of the governing equations, it is concluded that water uptake by a dehydrated disk is initially a passive rehydration process which becomes progressively more complicated by growth‐related water uptake (phase II) as the tissue water potential rises above −4 bars. Because of the operation of phase II, which begins initially at the cut edge of the disk and progresses inward with time, the interiors of leaf disks are prevented from attaining a water potential of zero. Instead, they are maintained at −0.2 to −3 or −4 bars, a factor that could lead to significant errors in relative turgidity determinations. Phase II neither starts immediately at a steady rate (Yemm and Willis hypothesis) nor waits for phase I completion before beginning (Barrs and Weatherley hypothesis). Rather, is predicted to begin immediately at a very slow rate and to increase monotonically until a steady, maximum rate is reached at the same time phase I is completed. For a 0.5‐cm radius disk and a tissue diffusivity around 10−5 cm2sec−1, phase II water uptake accounted for about 10 to 20% of the total water uptake after a floating time of 3 to 4 hours.
Sugarbeet Yield and Quality as Affected by Nitrogen Level1
Authors: Carter J. N. , Westermann D. T. , Jensen M. E. 
Published: July 2010

AbstractThis study was conducted, under several climatic and soil conditions, to determine the effect of N level on sugarbeet yield and quality and to further develop and refine both soil and tissue test methods for predicting N fertilizer needs for efficient refined sucrose production. Previous studies indicate that N fertilizer needs for maximum sucrose production may be predicted by considering yield potential and all N sources.Sugarbeets (Beta vulgaris L.) were grown under field conditions at N fertilizer levels varying from 0 to 448 kg N/ha on six sites throughout southern Idaho to determine root yield, sucrose percentages, sucrose yield, impurity index, and plant N uptake in relation to the residual NO3‐N, mineralizable N, fertilizer N, and petiole NO3‐N. These experiments demonstrated that the N fertilizer needs of sugarbeets can be determined by relating the root yield potential to the measured residual NO3‐N plus a measured or estimated mineralizable N level for an area. Optimum N level from all available soil and fertilizer sources has been found to vary between 5 to 6 kg/metric ton of beet roots produced. Using data from the current experiment and a previous study, N fertilzer could be predicted within 56 kg N/ha of that needed for maximum sucrose yield in 83% of the sites using measured NO3‐N and mineralizable N levels, 67% using measured NO3‐N and average mineralizable N levels, and only 12.5% using recommendations by fieldmen. Linear correlations were found between the total available N, total plant N uptake, other plant N variables, and root quality factors, like percentage sucrose and impurity index. These relationships confirm previous findings and will be useful for predicting root quality, optimum harvest date, and for verifying recommended fertilization practices. The use of the proposed soil and tissue test will improve root quality and sucrose production, as well as production efficiency, that will economically benefit the consumer, producer, and manufacturer.