bluuebunny/crossref_metadata_2025 huggingface dataset:
Morphological Effects of Moisture Stress on Burley Tobacco1
Authors: Ligon J. T. , Benoit G. R.
Published: July 2010

The effects of moisture stress, brought about by increased levels of soil moisture tension, on the morphological development of greenhouse‐grown burley tobacco plants were studied during the summers of 1963 and 1964. The tobacco plants were transplanted into cans (one plant per can) containing 160 pounds (oven dry basis) of Maury silt loam. The moisture treatments were, 1, to maintain the soil near 100% of available water, and 2, 3, 4, and 5, to return the soil to field capacity when the moisture decreased to 75, 50, 25, and 0% of available water. These percent available water values correspond to tension values of 0.25, 0.42, 0.96, 3.50 and 15 atmospheres, respectively. The results show that increased soil moisture tension resulted in decreases in total leaf area development, rate of leaf area development, and total dry weight of leaves (for treatments 3, 4, and 5). Irrigation of stressed plants resulted in increased growth rates which did not exceed the normal rates of continually nonstressed plants except as the nonstressed plants approached maturity. In addition, increased moisture tension delayed maturity, decreased quality, reduced stalk weight, and increased the ratio of leaf weight to stalk weight.
Influence of K on the Yield and Chemical Composition of Grasses Grown in Hydroponic Culture with 12, 50, and 75% of the N Supplied as NH4+1
Authors: MacLeod L. B. , Carson R. B.
Published: July 2010

The role of K in NH4+ utilization by three grasses harvested at the early vegetative, late vegetative, and early heading stages of development was studied in a greenhouse hydroponic experiment. Nitrogen was supplied at 250 ppm, with 12, 50, or 75% of the N in the form of NH4+ in solutions containing 50 or 250 ppm K. Orchardgrass produced the highest dry matter yield followed by bromegrass and timothy. A high ammonium source (75%) with low K (50 ppm) resulted depression of yield, reduction in tillering, increased mortality, and significant changes in the percent K, Ca, Mg, P in the plant tissue. Provision of adequate K (250 ppm) improved NH4+ utilization, increased the yield of forage and reduced the content of total, protein, and nonprotein N in the tissue. Potassium reduced the accumulation of tissue N in soluble or nonprotein form. Nonprotein nitrogen was the same at the late vegetative and early heading stages as at the early vegetative stage of development. The reduced nitrogen fraction which ranged from 0.3 to 0.8% with 50 ppm K was lowered to a range of 0.1 to 0.5% with 250 ppm K. Significant interaction effects for K and percent NH4+ showed that K increased the utilization of NH4+ nitrogen by grass and altered the percent of each nitrogen fraction present in the tissue.
Emergence of Corn in Relation to Soil Oxygen Diffusion Rates1
Authors: Wengel R. W.
Published: July 2010

Percent emergence of corn from soil was related to soil oxygen diffusion rates in an exponential manner. A “critical” diffusion rate range of 20–25 ✕ 10−8 g O2 cm−2 min−1 was indicated. Oxygen concentrations in the soil atmosphere may have been a factor affecting emergence independent of the oxygen supply based on plantinum electrode measurements.
Role of Reflected Light in the Corn Ecosystem1
Authors: Pendleton J. W. , Peters D. B. , Peek J. W.
Published: July 2010

At Urbana, Illinois, a 3‐year investigation of the effect of light reflection on corn yields has shown that a white reflective ground cover gave small, consistent corn yield increases over that on uncovered ground for 16 and 24 thousand plants per acre. The average yield increases for the 3‐year period were 12% and 7%, respectively. A nonreflective black ground cover provided average yield increases of 5% or less. The plastic was more effective in increasing yields when it was installed early in the season.

In recent years there has been considerable interest in the use of plastic ground covers for certain high profit horticultural crops. The data obtained in this experiment would suggest that consideration should be given to highly reflective plastic surfaces.
Effect of Imbalance of Boron Nutrition on the Peanut1
Authors: Harris Henry C. , Brolmann John B.
Published: July 2010

The ‘Florigiant’ variety of peanut (Arachis hypogaea L.) was grown 2 years in pot cultures on Lakeland fine sand, a soil deficient in boron, to determine the effects of imbalanced boron nutrition on peanuts. Variations in fertilization were: no treatment, complete fertilizer and lime treatment including the micronutrients, and the same as the latter except without boron. The containers were low‐boron and each held 60 pounds of soil. Reagent grade chemicals and distilled water, which was then passed through an ion exchange demineralizer, were used throughout the experiments. Flower counts, yields of shoots, roots and fruit and quality studies on the fruit were used to determine the effects of imbalanced boron nutrition. Without boron in the fertilizer, shoots were stubby, leaves frequently were mottled, dark areas appeared at the internodes of the branches, and stems sometimes cracked. Roots were also stubby and yields of fruit negligible. In contrast, plants with boron in the fertilizer were free of these abnormalities and produced many peanuts. With boron in the fertilizer, peak flower production came early in the flowering period, while without boron more flowers were produced but the distribution pattern was changed. With no treatment the plants were small, appeared normal, and yielded more peanuts of a better quality than plants with complete fertilization minus boron.
Correction for the Effect of Diatomaceous Earth on Moisture Content of Wheat as Determined by Capacitance Measurements
Authors: Johnson Robert M. , Kozak Adrian S.
Published: July 2010

Treatment of wheat with a diatomaceous earth dust gives rise to erroneous moisture content values as measured by the Motomco moisture meter. The moisture content of wheat, as determined by the official oven method, is not significantly changed by treatment with diatomaceous earth. The apparent decrease in moisture content, as measured by the Motomco moisture meter, can be compensated for by increasing the sample size. The amounts of wheat to be added to the usual 250‐g sample have been determined for four classe of wheat as follows: for hard red spring, hard red winter, and soft red winter, 7.5 g; for white wheat, 5.5 g. By use of this simple method, moisture contents of diatomaceous earthtreated wheats can be determined accurately with the Motomco moisture meter. The moisture values for the 250‐g untreated samples and the larger corrected samples of treated wheat do not differ significantly.
Variation in Zinc Content of Grain from Inbred Lines of Corn1
Authors: Massey H. F. , Loeffel Frank A.
Published: July 2010

The Zn content of the kernels of 29 inbred corn lines was determined, using seed collected over a 3‐year period from the experimental nursery at Lexington. In order to ascertain if the variation observed between lines in a given year was greater than that which might occur between replicates of a given line, an experiment using five lines of varying Zn concentration and five replications was performed.

Ky 211 had the highest Zn concentration in the kernel, 38.4 ppm. The next highest Zn concentration found was 26.3 ppm and the remainder of the 29 inbreds was rather evenly spread between this concentration and the lowest concentration found, 15.5 ppm. These differences were highly significant. The Zn concentration in the kernel was not closely related to the weight of the kernel or to the total weight of kernels per plant.
Corn Plant Maturity. I. Changes in Dry Matter and Protein Distribution in Corn Plants1
Authors: Johnson Ronald R. , McClure K. E. , Johnson L. J. , Klosterman E. W. , Triplett G. B.
Published: July 2010

Corn plants were harvested in six stages of maturity in 1962 and eight stages in 1964 to determine the distribution of dry matter and crude protein among the leaves, stalks, and ears. Changes in dry matter from July 20 to October 14 were 14 to 36% for stalks, 19 to 79% for leaves and 10 to 62% for ears. Highest total dry matter yield per acre appeared to be between the dent and glaze stages. No vegetative growth of the leaves and stalks occurred during visible ear growth and maturation. In both years, the ears constituted over 60% of the dry matter at maturity but did not reach this level until September 12, 1962 and October 6, 1964. The crude protein content of corn leaves declined rapidly throughout ear maturation while that of the stalks declined rapidly until 15 days post‐tasseling after which it declined only slightly.
Phosphorus Sources and Use in a Cropping Sequence on Silt Loam1
Authors: Lathwell D. J. , Musgrave R. B.
Published: July 2010

Both the initial and residual effects, of concentrated superphosphate (CSP), calcium metaphosphate (CMP), and fused tricalcium phosphate (FTP) were measured with corn, oats, and alfalfa on the alkaline (pH 7.5) Lima silt loam in two cropping series. The P sources were applied at different times in the cropping sequence during the 10‐year period of each cropping series. All three materials proved to be equally satisfactory sources of P both measured by initial crop responses and by residual effects. Rather modest quantities of P were adequate to satisfy the P needs of crops grown on this highly P deficient soil. Based on crop yields, a wide latitude of place of use of P in the cropping sequence was apparent in this experiment as a significant residual effect was observed throughout the experiment. The only restriction on use was that some P applied at the time of making the forage seeding was highly beneficial to subsequent forage yields. Corn responded equally well to residual P as to freshly applied P.
Effects of Years and Locations on Stalk Strength in Corn (Zea mays L.)1
Authors: Zuber M. S. , Loesch P. J.
Published: July 2010

Negative correlations between crushing strength of mature corn stalks and field stalk lodging have been shown by several workers. The objective of the study reported here was to determine the relative effects of years and locations on stalk‐crushing strength, rind thickness, and weight of 2‐inch stalk sections. Twelve inbred lines representing a wide range in inherent stalk lodging performance were grown at two locations for a 3‐year period. Data for the three stalk traits indicated a good agreement between locations within years while crushing strength and rind thickness varied more between years. Variation in crushing strength was attributed in part to pith destruction by stalk rots which are more prevalent in some seasons than in others. It was concluded that stalk quality data obtained in a single year at a single location would usually be adequate to screen a group of strains for inherent stalk lodging resistance. For greater precision data for more than one year and one location would be necessary. Crushing strength was affected more by different environments than the other two traits. The coefficients of variation for crushing strength ranged from 11.7 to 18.8%; rind thickness from 5.2 to 8.5% and weight of 2‐inch section from 8.7 to 13.0%.
Effects of Blade Removal and Nitrogen Level on Growth and Nitrate Content of Shoots of Reed Canarygrass1
Authors: Mittra M. K. , Wright M. J.
Published: July 2010

The work reported here considered effect of blade‐by‐blade defoliation and different levels of N nutrition on dry matter yield of individual shoots of canarygrass, accumulation of carbohydrate reserves in the underground organs, and nitrate content. Seven defoliation treatments were included at each level of nitrogen. These were: control, no blades removed (7‐8 blades); T‐3, To4, and T‐5 with 3, 4, or 5 top blades maintained, and B‐3, B‐4, and B‐5, with 3, 4, or 5 basal blades maintained. Nitrogen levels used were: 0, 10, or 30 ppm in sand culture experiments; and 0, 10, 25, 50, or 75 pounds per acre in experiments where soil medium was used. Top blades were more effective in supporting growth than were basal blades, confirming results of previous experiments. The nitrogen levels appeared to modify both the dry matter yields and the amount of recovery growth produced in the dark from the underground organs, when plants were grown in sand culture, and nitrate concentration decreased with an increase in the number of blades retained per shoot, the highest accumulation occurring when the smallest number of basal blades were maintained. There was an inverse relationship between total available carbohydrates and the concentration of nitrate in the aerial shoots.
Effect of Oxygen and Carbon Dioxide Concentration on the Germination of Range Grasses1
Authors: Dasberg S. , Enoch H. , Hillel D.
Published: July 2010

Four range grass species—Oryzopsis holciformis, Phalaris tuberosa, Agropyrum desertorum (Nordan and Fairway), and Agropyrum elongatum—as compared to wheat were germinated in atmospheres containing different concentrations of oxygen and carbon dioxide. The grasses, in the absence of CO2, showed significant decreases in the time rate of germination and in the final germination percentage over the whole range of oxygen concentrations tested; whereas wheat showed only a slight delay in germination with decreasing oxygen concentrations.

The initial (imbibitional) water uptake of all plants was not affected by oxygen concentrations, while the CO2 production (respiration) decreased at low O2 concentrations at this stage. Subsequently, the seed water uptake was parallel to the germination response.

The effect of CO2 (O — 15%) on germination was slight as compared to the oxygen effect.
Influence of Fertilization and Altitude on Energy Budgets for Native Meadows1
Authors: Grable A. R. , Hanks R. J. , Willhite F. M. , Haise H. R.
Published: July 2010

Experiments were conducted for 2 years near Gunnison, Colorado, to evaluate the influence of N fertilizer and altitude on energy budgets of native wet meadows. Measurements included evapotranspiration from lysimeters (Et), evaporation from Weather Bureau pans (E), net radiation (Rn), total short‐wave radiation (R2), soil heat flow (S), air and soil temperatures, wind velocity, precipitation, and forage yields.

During two periods of 1963, Rn, advected heat (A), and Et were slightly but not significantly altered at one location by application of N fertilizer. S was 2% or less of Rn, and A to lysimeters ranged from 6 to 11% of Et when data from all plots were averaged.

Studies during the entire growing season of 1964 at altitudes of 2240, 2350, 2670, and 3080 m indicated that Rn, Rs, and E cannot be used to accurately predict Et for high‐altitude wet meadows. Although changes in Rn or Rs were generally accompanied by changes in E or Et, the ratios of the values changed sharply during the season because of advected energy and crop harvest. During at least 1 or 2 weeks just before midseason harvest, S was negligible and sensible heat flux to the lysimeters (−A) was as much as 26% of Et; after harvest, however, S was about 20% of Et and sensible heat flux from the lysimeters (+A) was as much as 97% of Et. Et, E, and A (to lysimeters) during comparable periods generally decreased as altitude increased. The greatest photosynthetic efficiency obtained was about 2% of Rn; usually it was much less.
Effect of Soil Moisture Tension and Physical Condition of Soil on Utilization of Water and Nutrients by Potatoes1
Authors: Flocker W. J. , Timm Herman
Published: July 2010

A 3‐year study was made of the effects of irrigation on the nutrient content of potato plants grown in differentially compacted soil Changes in soil moisture tension and in rates of fertilizer application affected the nutrient concentration in the plants more than did the degree of soil compaction. The amount of water, number of irrigations, and timing of applications depended upon the mean soil moisture tension and varied with degree of compaction. Irrigating at a mean soil moisture tension of 0.5 atmosphere provided the most efficient use of water and fertilizer, regardless of degree of compaction. The use of instruments to aid in timing irrigation was emphasized. Measurement of the mean soil moisture tension yielded data potentially useful for conserving both water and nitrogen.
Response of Vicia Genotypes to Flooding1
Authors: Hoveland Carl S. , Donnelly E. D.
Published: July 2010

Three vetch species and 6 F7 lines from Vicia saliva (Ala. 1894) ✕ V. angustifolia (PI 121275) were grown in the greenhouse for 4 months under 4 flooding treatments: adequate watering but well‐drained, flooded 1 day in 10, flooded 2 days in 10, and flooded 4 days in 10.

Generally, herbage yield, root growth, and N content decreased with duration of flooding. For most vetch genotypes, greater Mn uptake by the plants occurred with prolonged flooding. Mn accumulation by V. angustifolia and V. sativa remained low in all treatments. Mn content was much higher in certain hybrids than in either parent, indicating transgressive segregation for accumulation of this element. Herbage growth of the V. angustifolia parent was less affected by flooding than any other entry.
Effects of Subsoil Management Practices on Growth of Flue‐Cured Tobacco1
Authors: Batchelder A. R. , Rogers M. J. , Walker J. P.
Published: July 2010

Following topsoil removal, tobacco, Nicotiana tabacum, was grown on exposed Appling sandy clay and Cecil clay subsoils. Some factors affecting tobacco growth on subsoils were 'determined, and the effectiveness of 3 management treatments on soil moisture conservation and tobacco yields was evaluated. The 3 treatments were: (1) bare surface, (2) straw mulch, and (3) straw mulch plus straw incorporated into the subsoil.

Leaf yields were significantly greater with the straw treatments than for the bare surface control during the first two seasons. In the third season, rainfall and supplemental irrigation were sufficient during critical growth periods and no differences occurred between those treatments. Mulching conserved soil moisture and reduced soil surface crusting. Treatment effects were comparable for both soils, but the yields were greater for the Appling subsoil. The data indicate that soil moisture is a primary factor influencing tobacco growth and yields on exposed subsoil.
Fertilizing Dryland Spring and Winter Wheat in the Brown Soil Zone1
Authors: Brown Paul L. , Campbell Ralph E.
Published: July 2010

Nitrogen and P fertilizers were applied to spring or to winter wheat to measure yield response during an 11‐year period at Huntley, Montana. The soil was a typical Brown soil of the Northern Plains, moderately low in plant available P. Annual precipitation averages 10 to 13 inches in this soil zone. In a wheat‐fallow cropping system, spring wheat grain yields were increased in only 1 year by NP fertilization and decreased in 1 year by P and by NP fertilization. During a 3‐year period, winter wheat yields were not increased by fertilization and were decreased by N and by NP fertilization in 1 year and by N fertilization in another year. Phosphorus and NP fertilizers caused accelerated growth and ,soil moisture use during early spring. Accelerated growth persisted until heading, then gradually disappeared. Soil moisture use was at a lower rate during the heading to maturity period because of decreased moisture supply. Both crops were under drouth stress during the critical heading to maturity stage.

With natural precipitation, spring and winter wheat grain yields averaged about 30% of the potential grain yield with soil moisture removed as a limiting factor. Because of the drouth stress, increased vegetative production usually did not carry through to increase grain yields.
Plant Height As A Factor Affecting Responses of Sorghum to Row Width and Stand Density1
Authors: Stickler F. C. , Younis M. A.
Published: July 2010

Three experiments were conducted at Manhattan, Kansas, from 1962 to 1964 to determine the extent plant height affected response to row width and stand density in three grain sorghum varieties. The experimental lines were isogenic differing by one gene (Dw3) and thus allowed the height effect to be determined within a common genetic background. Tall and short types averaged 57 and 37 inches, respectively, when mature.

Mean yield from 20‐inch rows exceeded that from 40‐inch rows by 502 pounds per acre, or 11%. There was little evidence for a row width by plant height interaction. However, plant height by stand density and plant height .by variety interactions were significant in each trial. The short genotype (dw3) performed better at high stand density (120 square inches per plant), but the tall genotype (Dw3) was superior at lower stand densities (240 or 360 square inches per plant). The plant height by variety interaction for yield and components of yield resulted largely from Redlan, the latest maturing variety used.
Pelleted Coastal Bermudagrass, Pelleted Whole Stalk Corn, and Ground Whole Stalk Corn with High and Low Concentrates for Lactating Dairy Cows1
Authors: Beaty E. R. , Miller W. J. , Brooks O. L. , Clifton C. M.
Published: July 2010

Following field drying, mature whole‐plant corn containing 32% grain on a dry matter basis was harvested and ground through a hammer mill. A portion was pelleted using 3% molasses as a binder. Because ground unpelleted material was extremely dusty, it was mixed with 20% molasses. Coastal bermudagrass was harvested at 3 weeks of age, dehydrated, and pelleted. In a continuous‐type experiment with 2 replications and 36 cows, the forages were each fed with a high and a low concentrate level for 8 weeks. The concentrates were fed at grain to FCM ratio of 1:5 and 1:2.5. Protein contents of the concentrates were adjusted to equalize intakes and to meet the requirements of the cows. Each cow received 3 pounds of long hay daily. Cows fed ground corn, corn pellets, and coastal pellets produced 29.7, 28.5, and 29.4 pounds of milk per day, respectively. Forage dry matter consumption was 31.2, 28.2, and 32.9 pounds per cow per day for the three forages. Milk composition percentages were: fat, 3.93, 3.62, and 3.80; protein, 3.66, 3.52, and 3.69; and SNF, 8.97, 8.85, and 8.93. Only the differences in fat and protein were significant. Cows fed the high level of concentrates consumed 3.3 pounds less forage dry matter but ate 2.1 pounds more total dry matter. Milk production was 1.0 pound higher for those fed the high level of concentrates but milk composition was not affected. It was concluded that each of the forages was a satisfactory feed and that they were essentially equal.
Variety Differences in Strontium and Calcium Accumulation in Seedlings of Barley1
Authors: Young W. I. , Rasmusson D. C.
Published: July 2010

Sixteen barley varieties were employed in a study of intraspecific differences in Ca and Sr accumulation. The effect of Ca/Sr ratio, pH, and various Sr‐89 concentrations and durations of feeding on variety differences were evaluated.

Significant differences were observed for Ca and Sr accumulation among varieties of barley seedlings grown in nutrient solution. Varieties high in Sr accumulation also were high in Ca accumulation. Two‐fold differences in accumulation were observed for both Ca and Sr‐89. The ratio of Ca to Sr in the nutrient solution had little affect on variety differences in accumulation of Ca or Sr. However, there was evidence that varieties differed in ratio of Ca to Sr accumulated in the shoots. The pH of the solution did not affect total Sr‐89 accumulation or variety differences. Both concentration and duration of feeding had a marked effect on total Sr‐89 accumulation, but no effect on variety differences.
Response of Two Alfalfas (Medicago sativa L. and M. falcata L.) to Time and Rate of Potassium Application in the Subarctic1
Authors: Klebesadel L. J. , Brinsmade J. C.
Published: July 2010

Annual topdressings of K at 0, 42, and 166 pounds per acre, applied either in spring or mid‐summer, were compared with 2 alfalfas—Medicago sativa (var. ‘Vernal’) and M. falcata—for 3 seasons in Alaska's Tanana Valley.

Stands of both alfalfas thinned rapidly during the study but stands and stand losses showed virtually no relationship to K treatments. Winterkill accounted for most of the reduction of stands and Vernal winterkilled more than M. falcata.

K treatments resulted in large differences in yield. Both rates of K topdressing resulted in higher alfalfa yields than no topdressing; and 166 pounds of K per acre were superior to 42 pounds per acre.

Crude protein content of forage was seldom influenced to a significant extent by K applications. Where differences existed, crude protein content was lowest with the highest rate of K application. M. falcata contained higher levels of crude protein than Vernal.

K content of forage, virtually always lowest where no K was topdressed, was usually higher in alfalfa topdressed with 166 pounds of K per acre than at the lower rate. K content was lower in Vernal than in M. falcata.

Highest percentage recovery in forage of applied K occurred with no topdressing. There, recovery exceeded the amount of K applied at planting. K recovery with the higher rate of topdressing was poorer than with the lower rate. M. falcata was superior to Vernal in K recovery.

Amounts of available K in the soil did not differ among treatments until the third harvest season, when K levels were higher in most plots that had received the higher rate of K topdressing.
Infrared Thermometry of Vegetation1
Authors: Fuchs M. , Tanner C. B.
Published: July 2010

Infrared thermometers with a bandpass filter from 8µ to 13µ can be used to measure the real temperature of vegetal surfaces with errors in the range of 0.1C to 0.3C. To do this the emissivity must be either known or determined and a correction accounting for the reflected radiation from the surroundings must be made. Values of emissivities found for dense canopies of alfalfa and of sudangrass were between 0.97 and 0.98. Emissivities of single leaves of snap bean and tobacco were 0.96 and 0.97, respectively. Depending upon the radiation of the surroundings corrections of +0.6C to +1.4C had to be added to the apparent radiative temperature of these surfaces in order to yield real surface temperature.
Effects of Row Width and Seedling Spacing on Yield and its Components in Grain Sorghum Grown under Dryland Conditions1
Authors: Karchi Zvi , Rudich Y.
Published: July 2010

Two experiments were conducted under dryland conditions in Israel in 1960‐61 to study the effects of population density and its distribution in the field on tillering, head weight, kernel weight, and yield of grain sorghum. Size of population and plant areas provided were found to be the major factors determining yield. Superior yields resulted from narrow rows combined with wide intrarow seedling spacing. Yield superiority was due primarily to increased number of heads per unit area, rather than to changes in head weight. Heads per unit area and the number of kernels per head were largely free of environmental effects. Kernel weight, on the other hand, was mainly affected by environmental conditions existing at the time of kernel maturation.

Interrelationships among yield components indicate that plant yields were inversely associated with the number of heads per unit area. Plot yields were equalized at the different seedling densities, mostly by changes in the number of kernels per head. Plot yields were directly associated with number of heads per unit area and inversely associated with head weights. Highest yields were obtained from 20,000 to 70,000 plants per acre, especially when planted in narrower rows.
Effect of Soil Treatments on Chemical Element Accumulation of Four Corn Hybrids1
Authors: Bradford R. R. , Baker Dale E. , Thomas W. I.
Published: July 2010

Four single cross corn hybrids, selected on the basis of the chemical element accumulation characteristics of their inbred parents in single‐cross hybrids, were grown under greenhouse conditions to determine the effect of different rates of calcitic and dolomitic limestone at two rates of K on accumulations of Ca, Sr, Mg, and K.

As was predicted from the performance of the inbred parents in other single cross hybrids, the four hybrids used in this experiment differed with respect to the concentrations of Ca, Sr, K, and Mg accumulated. Partial genetic control of chemical element accumulation by these hybrids was apparent. With respect to Ca and Sr accumulation the hybrids could be compared at any constant level of lime above 1/2 the L.R. with no significant change in rank order. At the lower rates of lime hybrid IV was relatively low in accumualtion of Ca, and addition of K to the soil caused a greater decrease in Ca accumulation by hybrid IV than was observed for the other hybrids. Hybrid II was a higher accumulator of Ca under all conditions than were hybrids I and III. On the other hand, the capacity of hybrid IV to accumulate Ca increased more with additions of calcitic limestone and decreased more with addition of K than was observed for the other three hybrids.

Within rates and sources of lime, accumulation of Ca and Sr were highly related, indicating that no genetic mechanism was operative in these hybrids to cause differential accumulation of these two elements.

The observations discussed suggest that antagonistic effects of one element added to soil on accumulation of other elements as well as accumulation levels of each element by these hybrids were under partial genetic control.
Growth, Yields, and Yield Components of Safflower as Affected by Source, Rate, and Time of Application of Nitrogen1
Authors: Gilbert Norris W. , Tucker T. C.
Published: July 2010

abstract

The effect of source, rate, and time of application of N on the yield and yield components of irrigated safflower was studied at Mesa, Arizona. Yield increased with each 50‐lb. increment of N up to 150 lb., applied as ammonium nitrate at planting in December. Further increases occurred when half was applied at planting and half in the spring. Urea at 50 lb. N preplant inhibited early seedling development, but yield was not lower than with ammonium nitrate at the same rate. Urea at 150 lb. N preplant resulted in failure to obtain stands in three replications and severe injury to seedlings in the remaining five. Ammonium nitrate at the same rate also resulted in some seedling injury but without significant stand reduction. Ammonium sulfate at the 50‐lb. N preplant rate gave higher yields than urea at the same rate, but not significantly higher than ammonium nitrate. Yield was correlated most strongly with numbers of heads per plant. Seeds per head was affected to a minor degree, but significant differences in seed weight did not occur.
Survival of Rhizobia on Pelleted Seeds of Trifolium Subterraneum L.1
Authors: Radcliffe J. C. , McGuire W. S. , Dawson M. D.
Published: July 2010

abstract

When Rhizobium trifolii was inoculated into 13 seed pellet coating materials, a wide variation in survival of the organisms was found. Five of six adhesives examined supported rhizobia growth. A tenfold improvement in rhizobia survival was obtained on pelleted subterranean clover seeds when the rhizobia were suspended in peat rather than broth. Only one of seven pelleting treatments using a peat suspension of rhizobia in 40% gum arabic had adequate numbers after 8 days.
Plant Nutrient Deficiencies and Related Tissue Composition of the Sweet Potato1
Authors: Spence J. A. , Ahmad N.
Published: July 2010

abstract

The visual symptoms which appear in sweet potato, Ipomoea batatas, under conditions of deficiency of nitrogen, sulphur, phosphorus, magnesium, potassium, calcium and iron are described. These symptoms were produced by growth of two node cuttings in sand culture. Results of tissue analysis for three harvests during the growth period are also presented.
Growth and Mineral Composition of Squash (Cucurbita pepo L.) as Affected by N, P, K, and Tobacco Ring Spot Virus1
Authors: Thomas J. R. , McLean D. M.
Published: July 2010

abstract

A sand culture study was conducted to measure the effects of N, P, K, and tobacco ring spot virus (TRSV) on growth and mineral composition of 'Yellow Straight Neck' squash. Concentrations of N at 56 and 224 ppm, P at 10 and 40 ppm, and K at 60 and 240 ppm were used in the presence and absence of virus. Largest dry matter yield was obtained with a nutrient solution containing the highest concentrations of N, P, and K. Nitrogen and K significantly increased female flower formation. Increasing the nutrient N concentration raised the N content and reduced the percentage of P and K in the total plant tissue. Phosphorus increased the total and alcohol‐soluble N content, whereas K decreased the total N content of the squash. The K content increased significantly as the nutrient K concentration increased.

Virus reduced yields only at the high concentrations of N and P. Presence of the TRSV decreased yield response to N and P, but had no effect on yield response to K. The most striking effect of virus on squash was the decrease in the number of female flowers. Virus‐induced reduction in female flower formation was greatest at the highest concentrations of N and P. TRSV significantly increased the N and P content of the squash, but had no effect on K.

Virus‐inoculated squash, grown in a nutrient solution containing 224 ppm N, 10 ppm P, and 240 ppm K, did not exhibit the systemic virus symptoms. Fruit produced on virus‐inoculated plants grown in this nutrient solution were also free of disease symptoms.
Water Relations and Growth of Beans (Phaseolus vulgaris L.) as Influenced by Nutrient Solution Temperatures1
Authors: Unger Paul W. , Danielson Robert E.
Published: July 2010

Experiments to develop and evaluate internal water stress in bean plants were conducted in controlled environment chambers under constant light, air temperature, and air movement conditions. Humidity was not controlled, but varied only slightly. The plants were grown in solution temperatures ranging from 10.0 to 32.5C to induce plant water stress.

Plant water stress, if it can be indicated by reduced water use and growth, occurred at 15.0C and lower solution temperatures. Leaf relative turgidity values were not greatly affected by treatments after the first day and measurements were not sufficiently sensitive to adequately evaluate differences in plant responses. Leaf sugar content increased with time for all treatments, but the greatest increases occurred at the low temperatures. Water use efficiency was increased by low solution temperatures, the increases being greater for top than for root production and greater for dry weight than for fresh weight.
Relationship of Tillage and Fertilization to the Yield of Alfalfa on Freeman Silt Loam1
Authors: Cary E. E. , Horner G. M. , Mech S. J.
Published: July 2010

Liming (L) and fertilizing with phosphorus (P) and sulfur (S) were more effective than any other combination (LP, LS, PS, LPS + N) of fertilizers used in increasing the productivity of alfalfa. Tillage and seeding practices were associated with degrees of frost heaving of alfalfa, but had no effect on production of alfalfa in the second and third cutting years. Plant heaving at the end of the first year following seeding was decreased by seeding alfalfa without a companion crop, by deep tillage, and to some extent by surface compaction.

Loosening the soil to a depth of 122 cm reduced average bulk density of the subsoil from 1.65 g/cc to approximately 1.45 g/cc. This treatment permitted greater water storage in the subsoil and an increased availability of subsoil water to plants through more extensive root penetration into the loosened zone.

Fertilization, combined with deep soil profile modification (with topsoil and subsoil mixed), produced the highest yield of alfalfa. The unfertilized deep‐tilled soil produced more alfalfa than the fertilized shallow‐tilled soil.

Mixing the topsoil and subsoil together to a depth of 122 cm sustained greater yields than tilling to the same depth but replacing topsoil and subsoil in their original sequence.
Population, Growth Rate, and Maturity of Vegetable Crops in Relation to Soil Salinity and Texture Under Sprinkler and Furrow Irrigation
Authors: Robinson Frank E. , McCoy Orval D.
Published: July 2010

Sprinkler irrigation as compared to furrow irrigation prevented surface salt accumulation which in turn led to higher plant populations. The sandiest soil produced a higher population of carrots and onions. Higher populations led to smaller average size plants. The driest irrigation treatment afforded better protection against onion bolting in early plantings. Variability in maturity of cabbage and lettuce was predicted by periodic dry matter sampling, In the sandier soil, the maturity of lettuce and cabbage was delayed 2 weeks.
Effect of Clipping Height on Forage Distribution and Regrowth of Pensacola Bahiagrass1
Authors: Stanley Robert L. , Beaty E. R. , Powell John D.
Published: July 2010

‘Pensacola’ bahiagrass, when grown in pots in the greenhouse, produced a majority of its forage below 5.08 cm in height. Grass fertilized with 84 to 336 kg/ha of N tended to produce a higher percentage of its forage above 5.08 cm than did bahiagrass receiving no N. Regrowth of bahiagrass was highest when clipped to 5.08 cm or less and lowest when allowed to grow to 10.16 or 12.70 cm. Regrowth of bahiagrass was highest at the high level of N fertilization and lowest when no N was applied. Clipping Pensacola bahiagrass to 2.54 cm or less for three times during the first season and four times the second season failed to seriously reduce its regrowth rate.
Phytotoxic Pesticide Interactions in Soil
Authors: Nash R. G.
Published: July 2010

Phytotoxic interactions resulting from pesticide combinations in soil and bioassay techniques for determination of such phytotoxic effects were investigated. A combination of dalapon with Di‐Syston, phorate, or carbaryl in soil resulted in additive phytotoxic effects. Diuron combined with Di‐Syston, phorate, or carbaryl produced synergistic phytotoxic effects. Captan combined with dalapon gave an independent effect, while chloranil was antagonistic toward the herbicidal activity of diuron. Dry rather than fresh weights were a more precise measurement of phytotoxic effects. Identification of phytotoxic interactions was not affected by growth durations of 3 or 5 weeks when oats were the bioassay plant. Combinations of more than two pesticides in soil usually did not result in third order interactions.
Tannin Content of Crown Vetich (Coronilla varia L.) Herbage1
Authors: Burns R. E. , Henson P. R. , Cummins D. G.
Published: July 2010

The tannin contents of three varieties of crown vetch from a cutting‐management study were found to be between 3.2 and 3.8%, about half that found in well‐managed sericea. The astringent fraction was approximately 30% of that found in sericea. Leuco‐cyanidin and leucodelphinidin were present in equal quantities. It is not likely that the small amount of tannin present, especially of the astringent fraction, would affect forage quality of crown vetch.
Accumulation of Sodium and Calcium by Seedlings of Some Cereal Crops Under Saline Conditions1
Authors: George Leon Y.
Published: July 2010

Barley, wheat, and rice have widely differing abilities to tolerate saline conditions. In a study of the amounts of Na .and Ca accumulated by seedlings under progressively increasing saline conditions, seeds were allowed to germinate in glass dishes on filter paper saturated with distilled water. Eight days after germination started saline solutions having osmotic concentrations of 0, 2, 4, 6, 8, 10, and 12 atm were added to each germination flask. After 24 hours of the saline treatments, seedlings were washed with distilled water and dried in oven. Sodium and calcium contents of shoots and roots were then determined by flame photometer. During the period of investigation rice accumulated more Na and Ca in both shoots and roots than either barley or wheat. Wheat accumulated more Na and less Ca in shoots than barley whereas the roots have less Na and more Ca than barley. Rice roots were less selective between both cations than those of barley and wheat.
Sustained Production of Blue Panicgrass, Panicum antidotale Retz., as Influenced by Management Practices
Authors: Holt Ethan C.
Published: July 2010

Blue panicgrass, Panicum antidotale Retz., frequently loses vigor following the year of establishment. The effect of cutting height, defoliation frequency, and nitrogen level on sustained production was studied at College Station and Iowa Park, Texas. Delaying harvest later than the boot stage had no advantage in yield in either the current or succeeding year and yield was less with greater stubble heights. Nitrogen increased yields but did not prevent a decline from one year to the next. Yields declined 38% at College Station and 56% at Iowa Park from the first to the second year of treatment. Uniform harvests in the third year indicated slightly favorable effects of some treatment combinations, but no combination prevented a decline in yield.
Leaf Area Indices and Nitrogen Uptake of Flue‐Cured Tobacco as Affected by Plant Density and Nitrogen Rate1
Authors: Miller R. J. , Langdale G. W. , Myhre D. L.
Published: July 2010

Effects of three plant densities and two nitrogen rates on leaf areas and nitrogen uptake by tobacco plants were studied during 1961 and 1962. A study was also made on the economics of these treatments.

Leaf area indices (LAI's) for both years increased with time until the reduction in total leaf area through loss of senescent lower leaves became greater than the gain in leaf area of the active upper leaves. The highest maximum LAI of 5 in 1961 was obtained for the high nitrogen rate and the 25‐cm spacing. The lowest maximum LAI of 2.5 was obtained for the low nitrogen rate and the 76‐cm spacing. LAI's increased with high nitrogen and at both levels of nitrogen the LAI's were in the order of 25 > 51 > 76‐cm spacings in 122‐cm beds.

Relationships between leaf area and leaf weight per plant were very similar during 1961 and 1962. Correlation coefficients for leaf areas and weights varied from 0.95 to 0.99 in 1961 and from 0.92 to 0.99 in 1962. In both years, better correlation appeared between leaf areas and weights at the high nitrogen rate than at the low nitrogen rate, with spacing treatments having little effect on the relationships.

Nitrogen uptake was much higher with the high nitrogen treatment than with the low nitrogen treatment.

The yield of flue‐cured tobacco increased with closer plant spacing and the higher nitrogen rate. However, leaf quality decreased with the high nitrogen rate and offset the higher yields in total dollar value per hectare. The quality of tobacco appeared to be influenced more by the nitrogen application than by the different plant spacings~ The most profitable treatment combination appeared to be the 76‐cm spacing at the low nitrogen rate.
An Inheritance Study of Resistance to Maize Dwarf Mosaic Virus in Corn (Zea mays L)1
Authors: Loesch P. J. , Zuber M. S.
Published: July 2010

The inheritance of host response to maize dwarf mosaic virus was studied under natural field conditions. Inbred lines 38‐11 (moderately resistant) and H55 (susceptible) and their F1, F2, BC1, and BC2 progenies were evaluated at two testing sites. Numerous variables, including the possible confounding effect of the presence of additional viruses inciting stunting in corn, prevented a valid classical Mendelian analysis. Genetic ratios proved meaningless due to substantial variation in disease scores even in true‐breeding entries. However, resistance appeared to be partially dominant, and indirect evidence from other studies in Missouri indicate that (1) resistance is due to more than one gene, or (2) the host plants respond differentially to a heterogeneous virus population.

Artificial inoculations of corn with pure isolates of maize dwarf mosaic virus are recommended for the determination of genetic ratios and gene numbers associated with resistance. But for experiments in the field in which the objectives are to determine the level of resistance and dominance relationships, diallel mating schemes employing F1 hybrids are recommended.
Effect of Relative Humidity, Temperature, and Light Intensity During Boll Opening on Cottonseed Quality1
Authors: Woodruff J. M. , McCain F. S. , Hoveland C. S.
Published: July 2010

Two laboratory experiments were conducted to study the influence of relative humidity, temperature, and light intensity during the boll‐opening period on cottonseed quality. Seed quality was reduced as relative humidity increased above 60% during a 21‐day exposure period. Increasing relative humidity from 60 to 70% caused a rapid decrease in rate of radicle growth of 5‐day old seedlings. Raising relative humidity to 80% and above resulted in a rapid increase in free fatty acids accumulated in seed oil during the exposure period.

Raising temperature of exposure period from 25 C to 40 C at constant relative humidities had little influence on seed quality. Increasing light intensity from 50 ft‐c to 2,000 ft‐c at 35 C and 80% relative humidity did not influence seed quality.
An Experimental Container Adaptable for Soil‐Crop Investigations under Greenhouse and Outdoor Environments1
Authors: Timm Herman , Perdue J. W. , Puri Y. P.
Published: July 2010

A wooden, box‐like container for use in crop‐soil investigations is described. The container provides a soil volume comparable to that for field‐grown plants and is easily assembled. Forklift tractor power is necessary to move a soil‐filled container. When insulation is provided, soil temperature in the container varies less than 5 C from field soil temperature. Potato tuber yield per plant in container soil was equal to field yield.
Vernonia anthelmintica: A Potential Seed Oil Source of Epoxy Acid. I. Phenology of Seed Yield1
Authors: Higgins J. J.
Published: July 2010

Vernonia anthelmintica (L.) Willd. was investigated as a potential seed oil source of epoxy acid. During the period 1963 to 66, phenological studies were conducted at Glenn Dale, Md. Fruit development stages of plants were identified quantitatively and related to seed yield. For highest seed yields, the optimum harvest period was found to be Sept. 15 to Oct. 1, with seeds planted May 1 to 18. Highest seed yields approached 1 metric ton/ha. Post‐frost harvests resulted in reduced yields.

Photoperiod influenced the time at which flowering occurred. Short days promoted flowering, but highest yields resulted from an intermediate photoperiod of 14 hours at planting with a reduced photoperiod after the first flowers began to develop.
Corn Silage Yield as Affected by Different Harvesting Techniques1
Authors: Mays D. A.
Published: July 2010

At a yield level of 10,000 kg/ha, harvesting corn silage at 45 to 75 cm above the soil instead of at 15 cm, topping above the ear, or making center‐cut silage decreased dry matter yields 1,960, 3,790, 2,110, and 5,901 kg/ha, respectively. Digestible energy levels were correspondingly reduced by 1,030, 2,110, 1,160, and 3,263 kg/ha.
Effect of Bulk Density and Seed Placement on Upland Rice Seedling Emergence
Authors: Varade S. B. , Ghildyal B. P.
Published: July 2010

An experiment was carried out under laboratory conditions to find out the critical bulk density and seed placement depths for upland rice seedling emergence. Aluminum cylinders were used to accomplish various combinations of bulk densities and depths of seed placement by compacting soil at moisture content of 9%. Seedling emergences was observed till the 10th day after sowing in a constant temperature incubator of 35 C.

Depths down to 8 cm with 1.6 g/cc or 0.7hg/cm2 pressures and lower densities and pressures were not limiting for seedling emergence when moisture was above field capacity. Depths beyond 8 cm with these densities and below 5 cm with 1.7 and 1.8 g/cc bulk densities seem to be limiting. The pressure of 2.8hg/cm2 at 10 cm depth became so critical that the emergence ceased totally. It seems that the mechanical impedance or the increased soil strength with increasing bulk densities affected seedling emergence adversely.