bluuebunny/crossref_metadata_2025_split huggingface dataset:
Deterioration of Alfalfa Swards in the Hot Humid Subtropics of India1
Authors: Bondale Kamalakar , Maiti S. , Chatterjee B. N. 
Published: July 2010

AbstractAlfalfa (Medicago sativa L.) planted in the humid subtropics of India has not persisted well. To determine the effects of management practices on persistence and production, herbage growth, plant populations, Fusarium incidence on roots, and total available carbohydrates (TAC) were determined.Seven P and K fertilizer regimes and two cutting frequencies were used with ‘Anand—2’ and ‘Sirsa‐9’ alfalfa cultivars sown in the fall of 1975, 1976,. and 1977 on an Antisol soil in the subtropical plains of the eastern region in India.In 1976‐1977 and in 1977‐1978, Sirsa—9 yielded 7.6 and 9.7 metric tons/ha, respectively, while Anand—2 produced 6.9 and 8.3 metric tons/ha, of dry matter, respectively. Major fertilizer yield response was almost linear for 0, 22, and 44 kgha of P. Response to K was minimal and only after plant P needs were satisfied. Response to P was greater in 1977‐1978,Plant populations decreased consistently during the summer to about zero in October 1976 and August 1977, while in 1978 in a better drained area plant populations in July reduced from 70 to 30%.Root weights decreased drastically from 172 days after sowing (DAS) to 263 DAS regardless of management factor in the first two seasons. Fusarium root rot incidence by 203 DAS was severe for all management treatments except for one K treatment. No relationship between incidence and herbage yield was evident, however. Plant density and disease seventy was positively correlated (r = 0.97). Total available carbohydrate concentrations decreased, also, from about 35 at 172 DAS to 18% at 263 DAS. A positive correlation of r = 0.74 was found between disease severity and TAC.Additional work is needed to delineate the effects of Fusarium, and soil and plant factors before alfalfa could be recommended as a perennial in the subtropical regions representative of the experimental area.
Effect of Liming on Potato Yields as Related to Soil pH, Al, Mn, and Ca1
Authors: van Lierop W. , Tran T. S. , Banville G. , Morissette S. 
Published: July 2010

AbstractThe objective of this study was to select the most dependable soiltest criterion for determining whether potato (Solanum tuberosum L.) yields might be increased by liming soils. To achieve this end, the crop was grown in unlimed and limed treatments of eight coarsetextured soils (Spodosols), with initial pH values ranging from 4.62 to 5.02 (H2O) and 4.32 to 4.76 (0.01 M CaCl2), in a greenhouse experiment. Liming at 8 g CaCO3/8 liter soil (≃ 2,000 kg/ha) increased the average tuber yield of three soils by 40%. No yield increases were, however, produced by liming soils which had pH values higher than 4.6 (0.01 M CaCl2) or 4.9 (H2O). Extractable soil Al (I N KCl) was as good an indicator as soil pH for predicting crop response to liming. Yields were generally not increased by liming when the concentration of extractable soil Al was < 0.90 meq/100 g. Manganese concentrations in soil or plants were not reliable indicators for predicting the response of this crop to liming. A relationship was found between the concentration of soil Mn extracted with either 1 N NH4OAc or 1 N KCl and the concentration of this element in plant tops (r ≃ 0.75**, significant at the 0.01 level); furthermore, the concentrations of Mn extracted by these solutions were related (r = 0.92**. The Mn content in plant tops also tended to decrease exponentially as soil pH increased (R2 = 47%). Finally, no Ca‐deficiencies were observed on these soils; apparently this crop can absorb sufficient Ca when soils contain as little as about 0.7 meq Ca/100 g (140 µg/g).
Tillage Effects on Soybean Nodulation, N2(C2H4) Fixation, and Seed Yield1
Authors: Lindemann W. C. , Randall G. W. , Ham G. E. 
Published: July 2010

AbstractPreviously, tillage has been shown to affect the yield of soybeans in southern Minnesota. The objective of this study was to determine if different tillage treatments also affected soybean nodulation and N2(C2H4) fixation. Six tillage treatments were sampled in 1975, 1976, and 1977 for nodulation and acetylene reduction activity. The six tillage treatments were part of a 12 tillage treatment experiment established in 1973 under a corn‐soybean rotation system on a Webster clay loam soil (fine‐loamy, mixed, mesic Typic Haplaquoll). Yield was significantly affected by tillage treatment with the yield of the no‐till treatment averaging 22% less than the other five tillage treatments. Few differences were noted in nodule number, nodule weight, or total acetylene reduction activity with respect to tillage treatment. Fall tillage tended to increase nodulation and acetylene reduction over spring tillage, but differences were small. Yield differences due to tillage practice were not attributed to changes in the N2‐fixation system of soybeans.
Seedbed Preparation and Planter Comparisons for Proso Millet Following Wheat1
Authors: Nelson L. A. , Fenster C. R. 
Published: July 2010

AbstractAdvances in herbicides and technology allows producers to replace long‐term (14 month) fallow periods with an additional crop in the semiarid region of western Nebraska. An example of an additional crop is when proso (Panicum miliaceum L.) is planted after winter wheat (Triticum aestivum L.) to give a wheat‐proso‐fallow rotation and allow two crops in 3 years. The purpose of this research was to determine the influence of four methods of preparing a seedbed (burn, plow, stubble mulch, and no till) in combination with three types of planting on yield and agronomic characteristics of proso following wheat. This study was conducted over a 6‐year period (1973–1979) at the High Plains Agric. Laboratory near Sidney, Nebr. on mesic Aridic Argiustoll soil.The results of this study indicate that neither the seedbed nor planter influenced proso grain yields and test weights, but plant heights, heading dates, and stand counts were influenced by both the seedbed and planter. Generally, no till resulted in lower emergence than burn, plow, and stubble mulch seedbed by 16, 14, and 12%, respectively. Proso planted in the stubble mulch and no‐till seedbeds were 6 and 12% taller, respectively, than proso planted in the burn and plowed plots. Interactions of seedbed, planters, and years influenced yield, test weight, height, heading date, and stand count which suggest that no one system is best under all conditions. The effects of summer rainfall on yield 'and stand count were positively correlated to the rain that fell after planting.
Cotton Boll Period Response to Water Stress and Pink Bollworm1
Authors: Kittock D. L. , Henneberry T. J. , Bariola L. A. , Taylor B. B. , Hofmann W. C. 
Published: July 2010

AbstractRapid cotton (Gossypium hirsutum L.) boll development and opening can be beneficial in late season. It can result in increased lint yield, earlier harvest, higher grade, less insecticide use, and reduced storm damage. Research was conducted in the field on a fine loamy, mixed (calcareous), hyperthermic, Anthropic Torrifluvent soil. This study evaluates the effects of water stress in late season (early irrigation termination) and pink bollworm [Pectinophora gossypiella (Saunders)] infestation on time required for cotton bolls to develop from flower to open boll in the field. Water stress speeded boll opening. Bolls from stressed cotton were obtained from field tests with five dates of final irrigation. They opened an average of 17 days earlier than bolls of unstressed cotton in late season. Boll period averages ranged from 41 to 76 days depending upon the degree of water stress and time of year. On droughty (shallow) soil [fine loamy, mixed (calcareous) hyperthermic Anthropic Torrifluvent], water stress effects were significant, but smaller. Delayed boll opening may explain reduced lint yield which at times is associated with late final irrigation. Pink bollworm infested bolls opened about 3 days earlier than non‐infested bolls in two tests with deep soil, but only 0.5 days earlier in a test on droughty soil. Boll period population resembled a normal distribution around the mean until 93% of the bolls were open. For a given day of flowering, 80 % of the bolls (from 10 to 90 %) opened within a 8‐ to 11‐day period.
Edaphic Requirements and Characteristics of Purpletop1
Authors: Boggess Neal , Baker Barton S. 
Published: July 2010

AbstractCool‐season forage species are of major importance to the livestock industry in the northeastern part of the United States. Growth of these species is characterized by periods of high production followed by periods of low production. Purpletop [Tridens flavus (L.) Hitchc.], a warm‐season grass species, makes its major growth during the summer months when cool‐season species are unproductive. It may have potential for reducing seasonal variations in forage production when grown in association with cool‐season species. In order to evaluate purpletop for forage purposes, more information is needed on its soil requirements and agronomic characteristics. In this investigation nine indigenous purpletop stands were studied relative to edaphic factors, management, and plant characteristics associated with the stands. A stepwise regression procedure was used to determine soil properties associated with the occurrence of purpletop. The sand fraction in the top 15 cm of the soil profile, as determined by a hydrometer method, was more closely associated with the occurrence of purpletop than any other factor studied. Soil pH, available P, K, Ca, and cation exchange capacity influenced the presence of purpletop in a complex interrelationship. Purpletop was found growing under different pH's, fertilities, and grazing systems, although none of the swards was under intensive management.Number of leaves (5.7), plant height (114 cm), panicle length (29.2 cm), blade length (40.8 cm), and blade width (12.7 mm) did not vary among sites, suggesting little genetic variation among indigenous populations of purpletop in West Virginia. Forage concentrations of P (0.21%), K (1.44%), Ca (0.22%), and Mg (0.14%) varied among sites but were related to soil levels of these minerals. No obvious problems were found that would suggest poor forage potential. Further investigations are needed to determine its place as a forage in livestock programs.
Effect of Landscape Position and Aspect on Soil Water Recharge1
Authors: Hanna A. Y. , Harlan P. W. , Lewis D. T. 
Published: July 2010

AbstractThe effect of landscape position and slope aspect on soil water recharge under dryland farming was studied in southeast Nebraska. North, south, and east‐facing slopes of Wymore silty clay loam (fine, montmorillonitic, mesic Aquic Argiudoll) were selected. Four positions were identified on each slope, namely, summit, shoulder, backslope, and footslope. Water content of the soil from 0 to 150 cm depth in 30 cm increments were measured weekly by neutron probe for 2 years. Daily precipitation was recorded. Soils of the north‐facing slope were 10 % less efficient in recharge of available water than soils on south‐ and east‐facing slopes during all recharge periods. Soils on footslopes were 6 to 8 % more efficient than other positions throughout the year. Water storage efficiency of the soil appeared to be higher in fall than in spring. Available water recharge was 9 % more efficient during the fall than during the winter‐spring period in all soils regardless of slope aspects and positions. High correlation coefficients (r) existed when soil available water was related to rainfall in either fall or spring recharge period.
Comparison of Bioassays for Atrazine Residue in Soils1
Authors: Brattain R. L. , Fay P. K. , Lockerman R. H. 
Published: July 2010

AbstractThe usefulness of a chemical‐fallow cropping system may often depend on the use of a herbicide bioassay. Several research bioassays have been used to detect phytotoxic soil residues. Some of these bioassays are inexpensive and accurate but are often criticized because of space and time limitations. Four bioassay methods were compared using atrazine [2‐chloro‐4‐(ethylamino)‐6‐(isopropylamino)‐s‐triazine] treated soil. Nursery cone‐containers filled with atrazine treated soil required little space and provided inexpensive, accurate results when compared to Petri dish assay techniques. Greenhouse pots were as accurate as the conecontainers but were more expensive and required more space. The Chlorella sorokiniana algae bioassay was the least expensive, fastest, and most accurate.
Nitrogen Fixation Capabilities of Plant Introduction Accessions of Pasture and Range Forage Legumes1
Authors: Walsh J. F. , Bezdicek D. F. , Davis A. M. , Hoffman D. L. 
Published: July 2010

AbstractMany legume species provide excellent quality forage, although the extent to which non‐cultivated species are able to fix N symbiotically is generally unknown. In this report 91 accessions of legumes from the genera Astragalus, Onobrychis, Lupinus, Hedysarum, and Oxytropis were tested for their ability to nodulate and fix N effectively. All accessions were obtained from the USDA Western Regional Plant Introduction Station at Pullman, Wash. Accessions were first screened by evaluating them in small plastic growth tubes. Eighty‐two accessions were nodulated by at least one Rhizobium strain and 53% of the accessions tested were judged to be effectively nodulated based on yield. All accessions that were identified as effective were then grown in Leonard jars and inoculated with single strains of rhizobia. Dry matter yield and nitrogen content were determined for all entries. Twenty‐seven accessions which were tested in Leonard jars were considered to have potential as effective N2‐fixing forage legumes based on comparison with N‐fertilized controls. The highest yielding entries were several A. cicer L. (cicer milkvetch) accessions and a single accession of H. coronarium L. (sulla). This survey has identified a number of accessions of each genus that may have potential for use in forage legume breeding programs.
Soybean Production Systems for Claypan Soils1
Authors: Gebhardt M. R. , Minor H. C. 
Published: July 2010

AbstractIn the Midwestern USA, early planting, narrow‐row spacing, and good weed control are recommended practices for soybean (Glycine max L. Merr.) production. Reduced tillage is being increasingly recommended as a means of reducing fuel use and soil erosion. Little multifactor research has been conducted to define the optimum combination of tillage, planting date, row spacing, and weed control. Two levels of each of these factors were tested in a 24 factorial experiment. Treatment levels for each factor were: planting date (1 May vs. 1 June); row spacing (38 vs. 76 cm); weed control (preemergence herbicides vs preemergence + postemergence herbicides); and seedhed preparation (conventional vs. no‐till). Additional treatment combinations evaluated the effects of mechanical cultivation in wide rows. The study was continued for 5 years on a Mexico silt loam, mainly Udollic and Mollic Ochraqualf soil near Columbia, Mo. Compared to their counterparts, average yield advantages for narrowrow spacing, conventional tillage, June planting, and preemergence + postemergenee weed control were, 5 (not significant), 31, 43, and 51 %, respectively. Lack of yield response of ‘Williams’ soybeans to narrowrow spacing and early planting was attributed to limited rainfall and incomplete weed control. Average weed control was 18, 12, and 31% better with conventional tillage, June planting, and herbicides applied preemergence and postemergence than with their counterparts. Other treatment comparisons showed no difference in soybean yields between bentazon (3‐isopropyl‐1H‐2,1,3‐benzothiadiazin‐4(3H)‐one 2,2‐dioxide) applied postemergence and two timely cultivations. The availability of improved herbicides for selective weed control along with improved planting equipment may lead to an acceptance of continuous no‐tillage for a corn (Zea mays L.)‐soybean rotation. Planting date should be planned so that critical stages of soybean development coincide with periods of probable moisture availability. When mid‐season rainfall is normally deficient, planting soybeans about 1 June may achieve better yields than earlier (1 May) plantings on soils with moisture‐holding characteristics similar to those of the silt loam Udollic and Mollic Ochraqualf soils of central Missouri.
Stockpiling of Three Tropical Forage Grass Species1
Authors: Omaliko C.P.E. 
Published: July 2010

AbstractDuring the annual dry season (October to March) in much of the tropics, supply of herbage for the livestock is limited. Hay and silage making are usual methods of conserving herbage but these methods are capital intensive and easily out of reach of the tropical pastoralist. Therefore, other methods of conserving herbage have to be evolved. In this study, stockpiling was used to conserve herbage. The main. objective of the experiment was to study the effects of four stockpiling periods on dry matter yields. Also, residual effects of management on the sward's productivity were assessed. Three forage species that are extensively used in grassland agriculture in southern Nigeria were stockpiled in 1977 and 1978 to provide dry‐season feed. The species were stargrass (Cynodon nlemfuënsis Vanderyst), elephant grass (Pennisetum purpureum Schumach.) and guineagrass (Panicum maximum Jacq). The four stockpiling periods were from either June, July, August, or September to November of each of the 2 years. Yield and quality of herbage from the poststockpiling cuts were estimated in December 1977, February and December 1978, and February 1979. On 15 May 1978 and 1979 residual effects of both the stockpiling and the subsequent post‐stockpiling dry season cuts on the swards performance were assessed. For the 2 year period, dry matter yields averaged over all three species were highest (7,330 kg/ha) and lowest (2,100 kg/ha) from the July and September stockpilings, respectively. The species varied in dry matter yields, and in the stockpiling period that gave the highest yields. Stargrass attained its highest yield from June stockpiling while the other two species were highest from July stockpiling. Elephant grass had a significantly higher dry matter yield (5,500 kg/ha) than either stargrass (4,370 kg/ha) or guineagrass (4,360 kg/ha). Yields from post‐stockpiling herbage cuts in December and February were low (390 to 1,800 kg/ha). However, the quality was relatively high for a herbage at this season—percentage crude protein (CP%) = 4.3 to 10.8; acid detergent fiber (ADF%) = 39.8 to 43.8; and total ash percentage = 4.7 to 12.4. There were no significant residual effects of stockpiling periods on the dry matter yields of herbage harvested early in the following season. These results suggest that stockpiling is an attainable method of providing good quality herbage during the dry season in the tropics. However, more studies involving different aspects of its management will still be required.
Thresher for Immature Soybeans1
Authors: Erbach D. C. , Burris J. S. 
Published: July 2010

AbstractSome experiments with soybeans [Glycine max (L.) Merr.] require harvest and shelling before complete maturation. A threshing mechanism was developed that orients and breaks the pods of artificially dried soybeans without damaging the seeds. The thresher orients the soybean pods by making use of the pod width‐to‐thickness ratio that is characteristically greater than one. The shelling is done by four wheels. Two wheels grip each pod and the other two crush it. The seeds then can be manually separated from the pieces of crushed pod. The thresher for immature soybeans significantly decreased threshing time when compared with traditional manual methods.
An Interactive Computer Program for Plotting Bar and Line Graphs1
Authors: Hannaway David B. , Fuhrer David , Fribourg Henry A. 
Published: July 2010

AbstractAn interactive computer program has been written for the preparation of bar and line graphs. This program incorporates features present in previously reported programs by other authors, adds additional capabilities and utilizes an interactive rather than batch mode of data entry. Rectangular graphs can be prepared with one or two X axes and one or two Y axes which can be drawn with different scales. Descriptive labeling, statistical designations, arrows, and super‐ and subscripting capabilities are available. Histogram charts have options for groupings of bars, tops on bars, and a choice of hatching types. Line graphs can be drawn in which symbols may be isolated or connected with dots, dashes, or combinations thereof. Mathematical functions defined by the user also may be plotted with the same options for symbol and line types. This program may be displayed on a grpahics terminal for interactive use and instructions given to route for final copy to a drum or flatbed plotter. Final graphs are suitable for publication. This program is written in FORTRAN 77, requires 43 K (4288010 words) to load and run, and presently is operational on a CDC Cyber 170/720.
Magnesium Nutrition and Grain Yield of Maize Having Low Water Potential1
Authors: Aparicho‐Tejo Pedro M. , Boyer John S. 
Published: July 2010

AbstractDrought decreases plant production but the nutritional status of the plants may alter their susceptibility. Because Mg is a regulatory ion for several aspects of chloroplast photosynthesis, the effect of Mg nutrition on the grain yield of maize (Zea mays L. cv. Dekalb XL43) subjected to a water deficit was examined during most of the grain‐filling period. Plants were grown at two soil Mg levels in a controlled environment capable of providing yields comparable to those in the field. The grain yield, shoot and root dry weight, leaf water potential (Ψw), and tissue mineral composition were determined. Immediately after tasseling, water was withheld from the soil of half the plants until the Ψw had decreased to −1.8 to −2.0 MPa, where it remained until maturity. Low water potentials resulted in a 50% reduction in grain yield and an accelerated leaf senescence. Despite small but significant differences in Mg concentration in roots, stems, and leaves, no differences attributable to differences in Mg nutrition were found in rate of plant dehydration, dry matter accumulation, or grain yield. It is concluded that differences in Mg content of the plant either 1) do not influence response to low − or 2) must be larger than we achieved to see an effect.