bluuebunny/crossref_metadata_2025_split huggingface dataset:
Relationship Between Corn (Zea mays L.) Yield and Leaf Levels of Ten Elements1
Authors: Peck T. R. , Walker W. M. , Boone L. V. 
Published: July 2010

AbstractCorn (Zea mays L.) yields were obtained at four locations from experimental plots receiving varying rates and combinations of N, P, and K. A quadratic polynomial was used to measure the relationship between leaf levels of N, P, and K, and corn yield. This function had an R2 of 0.45. A second quadratic polynomial using leaf (sixth leaf) levels of 10 nutrients, N, P, K, Ca, Mg, B, Cu, Fe, Mn, and Zn was fitted to yield, and resulted in an equation with an R2 of 0.81. From a potential of 65 linear and second order terms, 37 were fitted using a stepwise regression analysis procedure. The additional variation explained by the second regression model was statistically significant.Regression analysis of corn yields with leaf levels of 10 elements as independent variables revealed several significant main effects and interactions. The significant effect of numerous interactions indicates that the critical level of any particular nutrient varies with leaf levels of other nutrients. The significant effect of leaf levels of micronutrients upon corn yields indicates some merit in micronutrient research even though visual deficiency symptoms are not apparent.
Germination Response of Rice Seeds to Constant and Alternating Temperatures
Authors: Chaudhary T. N. , Ghildyal B. P. 
Published: July 2010

AbstractGermination response of rice seeds to constant temperatures of 4.5, 10, 15.5, 21, 26.5, 32, 37.5, and 43C and alternating temperatures of 41/24, 24/7, and 41C/7C with temperature periods of 8, 12, and 16 hours under high/low and low/high sequence was studied. No germination was observed at 43 or 4.5C. The maximum and the minimum temperatures for germination were found to be 41 and 7C. The temperature region of 26.5 to 37.5C appeared to be favourable for germination of rice seeds. Alternating temperatures as such showed no advantage over the constant temperatures. In case of inhibitive high or low temperatures, the alternation of temperatures promoted germination. Exposure of seeds to low temperature for 8 to 12 hours was more favourable than exposure for 16 hours. The sequence of temperatures did not show any definite effect.
Magnesium‐Phosphorus Interrelationships in Tomatoes
Authors: Hipp Billy W. , Gerard C. J. 
Published: July 2010

AbstractTomato (Lycopersicon esculentum) plants were grown in nutrient solution with Mg levels which varied from 0.96 ppm to 96 ppm and with P levels of 5 and 31 ppm. At low levels of Mg better growth was obtained when the P level was low. At high levels of Mg better growth was obtained when the P level was high. A nutrient solution containing 96 ppm of Mg promoted plant growth when the P concentration was 31 ppm but reduced growth when the P concentration was 5 ppm. Phosphorus fertilization of tomatoes grown on clay soils reduced the Mg content of the leaves from 1.2 to 0.65%. Analysis of leaves of commercial tomato fields during the late bloom stage showed a negative relationship between Mg and P (r = —0.896).
Photosynthesis under Field Conditions. XB. Origins of Short‐Time CO2 Fluctuations in a Cornfield1
Authors: Lemon E. R. , Wright J. L. , Drake George M. 
Published: July 2010

AbstractStudies of the vertical distributions of CO2 fluctuation in a cornfield were made in the 4‐to 0.25‐cycle/min frequency range. Amplitude of fluctuations decreased with height above the ground. Frequency in this range appeared rather constant, however. Sources and sinks for CO2 within the cornfield contribute to the fluctuations; however, eddy structure originating inside and/or outside the cornfield plays an important role too.
Relationship Between Soybean Yields and Leaf Levels of 10 Elements Determined with Different Regression Models1
Authors: Walker W. M. , Peck T. R. , Carmer S. G. 
Published: July 2010

AbstractSoybean leaf samples and yields were obtained from experimental plots receiving varying levels of P and K. Yields were regressed on a quadratic polynomial with leaf levels of P and K as variables. This regression had an R2 of 0.495. Yields were regressed on a second quadratic polynomial with leaf levels of N, P, K, Ca, Mg, B, Cu, Fe, Mn, and Zn as variables. With the stepwise regression procedure used for fitting the model, 22 linear and second order terms were fitted to the data. This regression had an R2 of 0.813. The additional variation accounted for by the second regression was statistically significant.Other polynomial regressions were fitted to the data using ratios of elements as independent variables, but none were superior to the quadratic polynomial in terms of R2 values.
Soil Water Supply and Depletion Pattern Differentiate among Zea, mays L. Single‐ and Double‐Cross Hybrids1
Authors: Bruce R. R. , Sanford J. O. , Grogan C. O. , Myhre D. L. 
Published: July 2010

AbstractThe relationship of irrigation response of several double‐ and singe‐cross Zea mays L. hybrids to inbred line composition and effectiveness in supplying the plant water requirements from the soil water supply was investigated. An experiment involving 25 double‐cross hybrids showed that 16 of these hybrids gave a 10% or greater grain yield response to irrigation, whereas the remainder showed very little or no yield increase. Certain hybrids produced about as well without irrigation as the highest yielding irrigation‐responsive hybrids. Subsequent experiments examined the irrigation response of several single‐cross hybrids and their double‐cross products. In a season of severe drouth requiring major irrigation, yield response of the double‐cross products to irrigation was predicted very well by averaging the yield response of the four non‐parental single crosses of the four inbreds involved.Examination of the soil water depletion pattern of single‐cross hybrids has shown that the yields are related to the capability of the plant to meet its water requirements during the critical fruiting period from existing soil water supply. Cited as examples are the cytoplasmic male‐sterile versions of several single crosses which rather consistently yield better than their fertile counterparts.
Translocation of Labelled Sucrose from Selected Cotton Leaves1
Authors: Sabbe Wayne E. , Cathey George W. 
Published: July 2010

AbstractStudies were made to determine the movement of metabolic‐14C from sucrose during flowering and fruiting of the cotton (Gossypium hirsutum) plant. The translocation and sinks were studied by using radioactive 14Csucrose applied at various locations on the plant and at various stages of plant development.Label from 14C‐sucrose was found to translocate from fruiting branches to roots of cotton plants before young bolls were initiated. However, upon initiation of bolls the roots did not continue as a major sink. At the time of first flower the label showed a tendency to translocate to regions of rapid growth (i.e., young bolls) both above and below the treated branch. There was a tendency for the fruiting branch more nearly in vertical alignment with the treated branch to receive a larger quantity of translocate than branches on the opposite side of the stem.When the osmotic pressure of the liquid nutrient culture was increased, the 24C‐label showed a tendency toward downward translocation during the flowering stage of the plant development. The radioactivity of the roots increased when the osmotic pressure of the nutrient solution was increased.
Effects of Sample Drying Procedure on Chemical Composition and In Vitro Digestibility of Coastal Bermudagras1
Authors: Wilkinson S. R. , Dawson R. N. , Adams W. E. 
Published: July 2010

Abstract‘Coastal’ bermudagrass (Cynodon dactylon L.) grown under three levels of N‐K fertilization and three growth intervals was air‐dried at 23C and over‐dried at 57C, 75C, and 100C to determine sample‐drying effects on cell wall constituents (CWC), acid‐detergent fiber (ADF), acid‐detergent lignin (ADL), and in vitro digestibility. Heat‐dried samples were compared with quick‐frozen, freeze‐dried samples from the same plots. Levels of N‐K fertilization were 224‐112, 672‐336, and 1,120‐560 kg N‐K/ ha per year, and growth intervals were of 2‐, 4‐, and 6‐ week durations under irrigated conditions.Oven‐drying increased CWC, ADF, and ADL contents of forage over those of freeze‐dried forage. Cell wall constituents were increased most at drying temperatures of 75C or above, with CWC content of immature samples being increased relatively more than that of mature samples. Acid‐detergent fiber content and ADL content were significantly increased by longer growth intervals, with one exception—ADL content of 2‐week‐old samples dried at 100C was similar to that of 6‐week‐old forage. In vitro digestibility expressed as percent dry matter disappearance was greatest in freeze‐dried samples and least in air‐dried samples. Growth interval and sample‐drying interacted in that 2‐week‐old, OD‐100C forage had similar digestibility to 4‐week‐old quick‐frozen, freeze‐dried forage. Differences in in vitro digestibility between the QF‐FD, OD‐75C, or OD‐57C were small and nonsignificant.Forage samples oven‐dried to constant weight at temperatures of 75C or less in 48 hours gave results representative of the agronomic treatment effects comparable to those of the quick‐frozen, freeze‐dried samples. Cells wall constituent fractions appeared most affected by oven‐drying; however, even though changes in response to growth interval and N‐K level were reduced by oven‐drying, interpretation of treatment differences were consistent.
Corn Earworm Injury to Maize as Affected by Plant Density1
Authors: Widstrom Neil W. 
Published: July 2010

AbstractWhen plant densities were varied for five sweet corn, Zea mays (L.), hybrids, a within‐row spacing of 30.5 cm sustained significantly less corn earworm (CEW), Heliothis zea (Boddie), injury than spacings of 61.0 and 90.5 cm during 2 of 3 years. Differences among spacing means for CEW injury could not be removed through adjustment by covariance techniques involving tiller number, days to mid‐silk, or husk extension as covariates. The present practice of avoiding non‐competitive plots when recording CEW injury must be continued if valid comparisons among hybrids are to be made.
Use of a Concurrent Mitscherlich Model in Fertilizer Evaluation1
Authors: Engelstad O. P. , Khasawneh F. E. 
Published: July 2010

AbstractA concurrent Mitscherlich model that can be fitted to a family of response curves via a multiple regression program is shown to be suitable for evaluation of fertilizers. This model provides for a common limiting yield and a common intercept, can be fitted by standard regression programs, and the coefficients obtained are compared readily by statistical tests.
Programmed Instruction in Soil Science: An Evaluation1
Authors: Shafer J. W. , Crabtree R. J. , Foth H. D. 
Published: July 2010

AbstractThe introductory course in soil science has been taught at Michigan State University since the fall of 1966 as a multimedia course. The lecture‐laboratory format was changed to include one lecture, one recitation and about three hours of nonscheduled programmed laboratory per week. The programmed part of the course consists of preparatory reading assignments, a taped‐slide presentation of new material and laboratory investigations, displays that are integrated with the tape presentation, and homework problems and questions. About two‐thirds of the students found this to be one of the most stimulating courses they have had in college. The integration of laboratory work with the lecture was preferred 2 to 1 over the traditional separation of laboratory and lecture. Staff found this approach more conducive to individualized help of students. Administrators find it easier to schedule courses, fewer pieces of scientific equipment are required, and there is more efficient use of space. Its major disadvantage is the extensive time required to develop the program and its initial cost.
Manganese Toxicity of Soybeans as Related to Soil and Fertility Treatments1
Authors: Parker M. B. , Harris H. B. , Morris H. D. , Perkins H. F. 
Published: July 2010

AbstractAn abnormal leaf characteristic of soybeans [Glycine max (L.) Merrill], described as crinkle leaf, was associated with high levels of water‐soluble soil and leaf manganese (Mn). Symptoms appeared on soybeans in a pot experiment using Hiwassee loam soil but were not evident on plants growing in Tifton loamy sand. An application of MnSO4, induced symptoms in soybeans on Tifton soil, and lime alleviated symptoms on Hiwassee soil. Symptoms included severe crinkling, interveinal chlorosis, necrotic spotting of leaves, and malformation of pods which resulted in more single seeded pods. Heavy rates of commercial fertilizer on a State loam soil in a field experiment caused similar leaf symptoms on soybeans. Symptoms in the field were associated with increased soil acidity, increased water‐soluble soil Mn, and high leaf Mn. Chicken manure applied at rates equivalent to commercial fertilizer N‐P‐K content slightly decreased soil acidity and produced normal plants. In the field, symptoms occurred at the pod‐fill stage during a period of high soil moisture. Yields were not affected by the toxic condition.
Water Pollution Potential Estimated from Farm Nutrient Budgets1
Authors: Frink C. R. 
Published: July 2010

AbstractEstimates of the yield of nutrients to waterways from wooded and cultivated land vary considerably. Some of this variability can be attributed to the large variability in the N and P content of runoff water, to analytic uncertainties, and to the difficulties of obtaining accurate flow measurements. As an alternative assessment of agricultural eutrophication, nutrient budgets were derived for the highly specialized dairy farms in the Northeast. This analysis showed that under certain conditions these dairy farms could contribute significant amounts of nutrients, particularly nitrate, to ground water. However, this loss of nutrients can be minimized by providing adequate cropland per cow, by selecting crops and animals that are efficient users of N, and by applying both manure and commercial fertilizers during the growing season.
Pangolagrass Performance under Different Levels of Nitrogen Fertilization in Hawaii1
Authors: Whitney A. S. , Green R. E. 
Published: July 2010

AbstractPangolagrass was grown on a Humic Latosol at 650 m elevation in an area of 170 cm average annual rainfall with relatively dry summers. Five levels of nitrogen from 0‐640 kg ha−1 yr−1 were applied as (NH4)2SO4 over a year period. Average annual dry matter (DM) yields ranged from 3,780 kg (control) to 18,000 kg/ha, and response to succeeding increments of N ranged from 30 units of DM per unit of N for the first increment (160 kg) down to 10 units for the 480‐640 kg increment. Yields were depressed when average night temperatures were ≤ 15C and during dry periods, but yields were significantly increased by fertilization even during these periods. Percentage crude protein fluctuated with season, being highest during the cooler months. Crude protein levels were influenced only slightly by low rates of fertilization but were raised by the higher N rates to levels sufficient to insure efficient utilization by livestock. The average production of forage under clipping indicated feeding capacities ranging from 1.1 animals (360 kg steers or heifers) per ha for the control to 7.5 animals per ha for the highest N level.Recovery of applied N increased from 36% for the first increment to 64% for the third increment, with a somewhat lower recovery for the final increment. Soil pH was reduced by 0.10‐0.15 units for each ton of (NH4)2SO4 applied. Liming the soil raised pH from 5.6 to 6.3 but did not influence yields of DM or crude protein. Critical levels for potash sufficiency were established at 0.11 meq/100 g of soil or 1.0% of the dry forage.
Effect of Gamma Ray Irradiation on Stability of FeEDDHA Solution at Two pH Levels1
Authors: Romney E. M. , Wallace A. , Wieland P. A. T. , Leo M. W. M. , Wallace G. A. 
Published: July 2010

AbstractIrradiation of FeEDDHA solutions with gamma rays from a Co60 source resulted in the same type of degredation of the iron chelate that sunlight causes. Effects of both types of radiation were more pronounced at low pH than at high pH. Hydrogen peroxide seemed to have a similar effect.
Effect of the Preceding Crop and Agronomic Practice on Sorghum (Sorghum bicolor L. Moench) and Groundnuts (Arachis hypogaea L.) in the Central Sudan1
Authors: Gerakis P. A. , Tsangarakis C. Z. 
Published: July 2010

AbstractThe influence of sorghum (Sorghum bicolor L. Moench), sesame (Sesamum indicum L.) and groundnuts (Arachis hypogaea L.) unfertilized and fertilized with N and P and of bare and weed fallow on the subsequent season's performance of sorghum and groundnuts was studied in 2‐year trials. The fertilizer rates of 50 kg/ha of N and 22 kg/ha of P applied to the first season's crops affected the yield of the second season's sorghum but not of groundnuts. Two consecutive years of sorghum or groundnuts was deleterious to the second season's yield. Symbiotic fixation in groundnuts was apparently low due to soil acidity and the absence of recent groundnut cultivation. Bare fallow increased moisture by 7.4 mm in the top 1.0 m of soil as compared to weed fallow, but the increase was not reflected in the yield of either crop.
Measuring Thickness of Excised Mature Corn Pericarp1
Authors: Wolf M. J. , Cull Irene M. , Helm J. L. , Zuber M. S. 
Published: July 2010

AbstractPericarp thickness of 19 corn (Zea mays L.) samples was determined by two methods: by microscope and by micrometer. Either kernels were frozen and 40 µ sections cut, stained, and measured with an ocular micrometer or kernels were presoaked and pericarp strips were excised for measurement. The excised strips were measured with a plunger micrometer. The coefficient of rank correlation was +0.85**, indicating good agreement between the two methods. The microscopic method produced greater thickness values than the micrometer method. The lower values were probably due to a certain amount of compression by the micrometer plunger. Germinal‐abgerminal ratios differed while right and left sides of the kernels were similar. The excision method is the more economical of the two and does not need specially trained laboratory technicians.
Effect of Moisture Stress at Different Stages of Growth I. Comparison of a Single‐Eared and a Two‐Eared Corn Hybrid1
Authors: Barnes D. L. , Woolley D. G. 
Published: July 2010

AbstractSingle‐eared (Hy × C103) and two‐eared (R71 × B60) corn (Zea mays L) hybrids were grown with their roots confined in 8− ✕ −24‐inch plastic‐lined, soil‐filled trenches. They were subjected to equally severe moisture stress at tassel emergence, silking‐pollination and blister kernel stages. The two‐eared variety was more tolerant to moisture stress at the pollination and blister kernel stages than the single‐eared variety. There was no significant difference in the total grain yield of the varieties to the moisture stress at tassel emergence. Silking was delayed in both varieties during moisture stress at pollination; however, this delay in silking did not reduce the fertilization of the ears and the grain yields of the two‐eared variety as much as the single‐eared variety.The two‐eared variety extracted significantly more water (1–2%) from the soil when under moisture stress.A method for measuring the relative turgidity (RT) of the leaves of the corn plants was developed, and the RT of each leaf on the corn plant was different. The RT decreases from apex to base, with each succeeding leaf. Moisture‐stressed corn plants had RT values 18 percent lower in the leaves near the ear shoot than in the leaves near the tassel. This difference in RT could account for the lack of silk emergence while the tassels continued to shed pollen.
Annual Bluegrass Control in Overseeded Bermudagrass Putting Green Turf1
Authors: Bingham S. W. , Schmidt R. E. , Curry C. K. 
Published: July 2010

AbstractDCPA, bensulide, and diphenamid gave preemergence control of annual bluegrass in freshly tilled soil. Overseeding bermudagrass golf greens with cool season grasses reduced through competition the amount of annual bluegrass cover and provided a desirable putting surface. Annual ryegrass was more effective in this respect than red fescue. Bensulide and DCPA gave control of annual bluegrass and the rates required were partially offset by competing cool season grasses. The cool season grasses seeded one month after treatment were not affected by 5.6 kg/ha of bensulide whereas higher rates gave significant reductions in ground cover with cool season grasses. The margin of safety was not as great with diphenamid. Although bermudagrass growth was retarded in spring with the overseeded cool season grasses, the turf quality was maintained better with the transition from the overseeded grasses to bermudagrass than from the infested annual bluegrass to bermudagrass. Plant competition reduced the number of tillers and weight of annual bluegrass plants in the field and greenhouse studies.
Evaluation of Dewatering and Wilting as Moisture Reduction Methods for Hay‐Crop Silage1
Authors: Derbyshire J. C. , Gordon C. H. , Holdren R. D. , Memear J. R. 
Published: July 2010

AbstractThe wilting and dewatering methods of reducing alfalfa (Medicago sativa L.) moisture prior to ensiling were compared with the direct‐cut harvesting procedure. Field dry matter losses from wilting were essentially zero and were high for the dewatering method. Because of large storage losses of direct‐cut silage, total dry matter losses from the field to the cow were similar for the two nonwilted methods but five times greater than for wilting. Silage temperatures were similar for the three harvesting systems, but silage dry matter bulk density was greatest for the wilted method. Both methods of reducing forage moisture reduced the percentage of the more soluble plant fractions. These differences were not as marked after fermentation. Milking cow response was similar on the three silages in spite of small differences in energy consumption. Wilting appeared superior particularly when animal product per unit of crop land is dominant.
Yield of Corn on Frederick Silt Loam as Affected by Slope and Fertility Treatments1
Authors: Lutz J. A. , Hawkins G. W. , Hoepner P. H. , Martens D. C. , Porter H. C. 
Published: July 2010

AbstractExperiments were conducted on a B slope (2.5‐7.5%) and on a C slope (7.5‐15%) in 1963, 1964, and 1965, to measure the response of corn {Zea mays L.) on Frederick silt loam to five levels of N applied with three rates of K. Both grain and silage yields were measured. Combined data for the 3 years showed a grain and silage response to only 67 kg N/ha on the B slope, but 134 kg N/ha was required to attain maximum yields on the C slope. Silage yields were increased by 70 and 140 kg K/ha on the B and C slopes, respectively. Grain yields did not respond to applied K on the B slope, but there was a response to 70 kg K/ha on the C slope. Both grain and silage yields on both slopes were similar the 1st year but higher on the B slope in the other 2 years.
Influence of Caging and Pesticide Drenches on Yield and Persistence of Red Clover, Trifolium pratense L.1
Authors: Zeiders K.E. , Newton R. C. , Graham J. H. 
Published: July 2010

AbstractDrenching of field plots with insecticides resulted in a highly significant increase in yield in each of three harvest years. Fungicide drench had little or no effect on yield and was discontinued after the first harvest year. A significant increase in yield due to caging was observed in 1966 and 1967. Effects of both insecticides and caging on stand survival were highly significant in 1967, but nonsignificant in preceding years. Caging decreased the incidence of virus disease and foliar insect damage, and the percentage dry matter of forage in both check and insecticide‐treated plots. External root rot was severe on all surviving plants after 39 months regardless of treatment. Insecticides favored root growth as evidenced by larger crown diameters.