bluuebunny/crossref_metadata_2025 huggingface dataset:
Growth, Chemical Composition, and Yield of Safflower as Affected by Exchangeable Sodium1
Authors: Werkhoven C. H. E. , Fireman M. , Miller M. D.
Published: July 2010

In greenhouse experiments, safflower was grown on a Yolo fine sandy loam, fertilized with N, P, and K, and treated with a NHCO3 to give six levels of exchangeable Na, ranging from about 2 to 45% with very little salinity. Half of the soil in each of the trials had received “Krilium” soil conditioner (0.2% by weight), the other half had not. A single lot of soil was used to grow two crops in succession, both of which were harvested prior to flowering. A third crop was grown to maturity on a second lot of soil. The exchangeable sodium percentage (ESP) remained reasonably constant during cropping. Increasing ESP levels up to 20 and 30% resulted in greatly increased growth as measured by dry weight of the tops. ESP levels higher than these were detrimental to growth and yield. Increasing the ESP decreased the K, Ca, Mg, and P, and increased the Na content of the leaves. The maximum seed yield and oil percentage occurred at ESP values of about 20 and 30 respectively. The seed yield was greatly increased by “Krilium”, and at ESP 20, the total oil yield was twice as high as that of the check. The fatty acid composition of the oil appeared to be unaffected by ESP levels.
Relationships Between NO−3‐N in Petioles During the Growing Season and Yield Components of Sugar Beets (Beta vulgaris)1
Authors: Hale V. Q. , Miller R. J.
Published: July 2010

Sugar beets grown at 3 levels of nitrogen fertilizer and 4 irrigation frequencies were harvested on 3 different dates. Petiole samples were taken at about monthly intervals and analyzed for NO3−‐N. These nitrogen values were correlated with sugar yield at each harvest to determine the suitability of such analyses in predicting an optimum harvest date. The irrigation treatments had no effect on yield of roots or sugar. High nitrogen rates increased beet root yields at the last harvest date and decreased the sugar percentage at all harvest dates. However, NO3−‐N content of the petioles was not sufficiently correlated with sugar yields to be useful in predicting an optimum harvest time for maximum sugar production. With progressively later harvest dates, sugar yield per acre showed increased correlation with beet yield and decreased correlation with percent sugar.
Influence of Macronutrient Elements on the Amino Acid Composition of Soybean Plants1
Authors: Haghiri F.
Published: July 2010

Greenhouse experiments were conducted to study the effects of various levels of N, K, Mg, Ca, P, and S on the concentration of amino acids in soybean plant hydrolyzates. Deficiency and excess amounts of N increased the amino acid contents (µ mole/g dry tissue) in the tops, while in the roots the amino acid contents increased as N concentration increased in the root media. Aspartic acid, arginine, and histidine contents of tops were affected most by N treatments. Although the percent N of potassium deficient soybean tops was higher than those plants receiving potassium, their total amino acid contents were of the same order of magnitude. A negative correlation was found between the aspartic acid content of the soybean tops and the potassium concentration of the nutrient media. Similar results were obtained for plants grown at various Mg levels. Calcium levels had little effect on the concentration of amino acids in soybean plants. Increased arginine and aspartic acid and decreased glutamic, proline, glycine, alanine, valine, and leucine contents were noted with P deficient plants. The total amino acid content was highest at 30 ppm P level. A positive correlation was noted between the total amino acid content of tops and the sulfur concentration of the root media. In general, high amino acid contents were found in plants grown under conditions where the macroad micro‐nutrients were present in sufficient amounts and proper balance.
Method for Calculating the Photosynthetic Response of a Crop to Light Intensity and Leaf Temperature by an Energy Flow Analysis of the Meteorological Parameters1
Authors: Idso S. B. , Baker D. G.
Published: July 2010

The productivity of plants is highly correlated with light intensity and leaf temperature. By an energy flow analysis of the meteorological parameters it is possible to calculate the daily variations of these two factors and predict the photosynthetic response of a crop. To do this a plant is considered as being composed of several different characteristic types of leaves. An energy balance equation is derived for each type and solved for the leaf temperature. Knowing leaf temperature and light intensity, photosynthetic rate curves are then constructed for the different types of leaves. An analysis of the crop geometry gives the fractions of the total number of leaves each characteristic leaf type comprises. The photosynthetic rate curves of the different leaf types are then multiplied by these fractions and added together to give an average photosynthetic rate curve for the plant (and thus the crop) as a whole.

Results are presented for a hypothetical crop at the beginning of growth, and at times of 50% and 100% ground cover. The effect of crop development through the growing season in modifying its energy environment and thus its rate of photosynthesis is made strikingly clear by this comparison.
Winter Oat Yields from Low Test Weight Seed1
Authors: Rothman Paul G. , Bowman Donald H.
Published: July 2010

This study was undertaken to determine if low‐test‐weight winter seed oats are suitable for planting. We used 8 lots of ‘Victorgrain 48—93’ oat seeds, with test weights ranging from 28.3 to 46.3 kg/hl.3 No significant differences in yields were obtained when 3 rates of seeding of both treated and nontreated seed were tested. Furthermore, no relationship existed between initial seed weight and seed weight of the resulting crop.
Distribution and Concentration of HCN in a Sorghum‐Sudangrass Hybrid1
Authors: Wolf D. D. , Washko W. W.
Published: July 2010

Dry weight and HCN concentration were determined in several parts of a sorghum‐sudangrass hybrid. Leaf blade minus midrib was high in HCN at all growth stages but contributed decreasing amounts of total plant dry weight. Midrib, sheath, and stem portions decreased in HCN concentration with maturity. Decrease in HCN potential of the entire plant was due mostly to the proportional increase in weight of low‐HCN‐containing parts.
A Rapid Calendar Date Counter1
Authors: Abel George H.
Published: July 2010

A wheel counter was made to count days and schedule dates of events in the calendar year easily and rapidly. Construction plans are available.
Effect of Root Temperature Variation on Growth and Transpiration of Cotton (Gossypium hirsutum L.) Seedlings1
Authors: Nelson L. E.
Published: July 2010

The roots of 2‐day old cotton seedlings growing in nutrient solution were subjected to 24, 18, and 12 C for 4 days and then grown an additional 7.5 days at 24 C. Air temperature was 27 C, the saturation deficits varied between 15 and 17 mb., and light intensity was 600 ft‐c. Fresh weights, dry weights, leaf area, and water use decreased as root temperatures decreased. Little or no growth occurred at 12 C during the 4‐day treatment period, but growth resumed after return to 24 C and the rate was the same as the 24 C treatment. The detrimental effect of a short period of low root temperature was apparently caused by a reduction in water uptake which in turn decreased leaf expansion.
Alfalfa Seed Chalcid (Bruchophagus roddi Guss.) Infestation Cycles in Relation to Alfalfa Seed Production and Sampling for Resistance in Southern California
Authors: Lehman William F.
Published: July 2010

Infestations of alfalfa seed chalcid were studied on varieties and clones through three seasons in a low desert valley area of Southern California. Chalcid infestations were moderate (35 to 55%) in one test when seed was collected in late April and May, high (59 to 77%) in 1 year and low (16 to 27%) in the other 2 years during June and early July, low (10 to 33%) from the middle of July to the first part of August, and high (60 to 90%) from the middle of August through October in all 3 years. Twenty‐two clones were tested for reaction to the chalcid. Four had some tolerance and may be valuable in breeding for resistance. Seeds per raceme varied among clones and through the seed production season. Correlation coefficients between chalcid infestation and seeds per raceme were very low (r = −.16 and +.05) when based on the average reaction among clones but moderate to high (r = + .53 and +.99) when based on the average reaction among dates in the same tests.
Factors Affecting the Persistence of Picloram in Soil1
Authors: Merkle M. G. , Bovey R. W. , Davis F. S.
Published: July 2010

The effect of soil type, temperature and moisture on the persistence of 4‐amino‐3,5,6‐trichloropicolinic acid (picloram) was determined using vapor phase chromatographic analyses and plant bioassays. Detectable quantities of picloram were present in Houston clay, Axtell sandy loam, and commercial sand after incubation for 1 year, at 4, 20, and 38 C and at moisture levels of field capacity and 0.1 field capacity from rates as low as 0.25 #g per g (½ lb/A). Movement studies indicated that leaching was an important means of dissipating the herbicide in light soils. Photodecomposition may also be important if the herbicide remains on the soil surface for long periods of time.
Selection of Index Leaf for Studying the Critical Concentration of Nitrogen in Rice Plants1
Authors: Wallihan E. F. , Moomaw J. C.
Published: July 2010

Changes in nitrogen (N) concentration in the last four leaves formed on rice (Oryza sativa L.) culms of three varieties growing in paddy in the Philippines during the rainy season were studied during the period from formation of flower primordia until after flower emergence. On the basis of stability of N concentration and sensitivity to N supply, the blade of the next‐to‐last leaf (second leaf below the panicle), excised at the time of flower emergence, was chosen as the index leaf.
Parameters of a Chlorinated Pyridine Phytotoxicity to Robinia pseudoacacia1
Authors: Rieck C. E. , Lynd J. Q.
Published: July 2010

Soil factors influencing phytotoxicity of the specific nitrification inhibitor, 2‐chloro‐6‐(trichloromethyl) pyridine, N‐Serve, was determined with a Typic Quarzipsamment, Eufaula sand, for Robinia pseudoacacia L. Narrow C:N ratio, 2.88% N, soil organic matter amendment, and increased temperatures to 38 C increased N‐Serve effectiveness. Soil sterilization treatment reduced N‐Serve activity. A highly active form of this pyridine accumulated in black locust foliage.
Estimation of Optimum Plot Size and Shape for Grain Sorghum Yield Trials1
Authors: Brown A. R. , Morris H. D.
Published: July 2010

Grain sorghum was planted to a uniform stand on Cecil sandy loam soil which had been fertilized with 408 kg/ha of a 4.0‐5.3‐10.0 (4‐12‐12) fertilizer. The plants were sidedressed with 56 kg/ha of nitrogen. Heads were harvested and threshed from 1‐row plots 1.52 m long. Yields from these plots were combined in various combinations of rows and row lengths to determine the optimum plot size as measured by coefficients of variation.

Data from this 3‐year study involving different size and shape of plots for grain sorghum indicated that the optimum size plot consisted of 2 rows 4.56 m (15 ft) long.
Effect of Topdressed Nitrogen and Potassium on the Feeding Value of Orchardgrass Hay for Lactating Dairy Cows1
Authors: Martz F. A. , Brown J. R. , Das B. K. , Padgitt D. D.
Published: July 2010

Twenty lactating Guernsey cows were used to compare the feeding value of four orchardgrass (Dactylis glomerata) hays from established fields which received different combinations of topdressed nitrogen and potassium fertilizer. A 4 ✕ 4 Latin square changeover design was used. Grain and beet pulp consumption was held constant and hay was fed ad libitum throughout this trial. The average daily dry hay intake was 1.10, 1.06, 1.14, and 1.00 kg per 100 kg body weight for the treatments P, PK, NP, and NPK, respectively. Consumption of hay NPK was significantly less than the consumption of the other hays at the 5% level of significance. The average daily production of fat corrected milk was 11.45, 10.84, 11.14, and 11.19 kg for the hays from treatments P, PK, NP, and NPK, respectively. There were no significant differences in milk production from any of the hays. Top dressing with a complete fertilizer mixture containing 120 kg N and 186 kg K per hectare nearly tripled the hay yield and quadrupled the crude protein yield over top dressing with phosphorus alone.
Use and Evaluation of T‐S‐T for Improving Agronomic Teaching1
Authors: Pennock Roger
Published: July 2010

Projected transparencies have proven a highly effective teaching aid in several agronomy courses but have had the disadvantage of being difficult to review as compared to lecture material. To overcome this problem, a T‐S‐T program was developed in which students can, at their convenience, review transparencies with accompanying narration from a tape recorder. The benefit to students was measured by comparing results of tests given with and without use of the T‐S‐T program. The mean score improved by 9.3 points which was significant at p = .05.
Evaluation of Several Kentucky Bluegrass and Red Fescue Strains Maintained as Lawn Turf under Three Levels of Fertility1
Authors: Skogley C. R. , Ledeboer F. B.
Published: July 2010

Turfgrass performance of eight selections of Kentucky bluegrass and six red fescues under three levels of fertilization was studied from 1962 through 1964. Fertilizer treatments consisted of applications of a 10‐6‐4 grade at 4.88 kg/100 m2 in spring, in spring and fall, and in spring, summer and fall. Visual ratings of turf quality were made at approximately monthly intervals during the growing seasons.

Quality of turf improved markedly, particularly with bluegrasses, with each additional fertilizer application. More than two annual applications did not greatly increase fescue quality, however. ‘Park,’ ‘Delta,’ and K‐5(47) Kentucky bluegrasses performed better than other bluegrass varieties when fertilized only once a year. K‐l(51) and K‐5(47) were clearly superior when three annual applications were made. Common Kentucky bluegrass gave inferior results at all fertility levels.

Frequency of fertilizer application had little effect on the order of response among the fescues. ‘Jamestown’ (R.I. No. 6) was rated highest at each fertilizer level and ‘Pennlawn’ was second. ‘Rainier’ and creeping red gave the poorest response at each fertilizer level while ‘Chewings’ and ‘Illahee’ were intermediate.
Iron Uptake by Two Citrus Rootstock Species in Relation to Soil Moisture and CaCO31
Authors: Wallihan E. F. , Garber M. J.
Published: July 2010

Pot cultures were used to study the effects of soil water suction, presence of CaCO3 in the soil, and two species of rootstock, Citrus Aurantium L. and Citrus sinensis (Linn.) Osbeck, on iron uptake and iron sufficiency. Iron concentration in standard leaf samples was used as the measure of iron sufficiency; total leaf iron per plant was used as the measure of uptake.

Iron uptake was proportional to the weight of the root system (r = .92) when water suction was varied; this supports the hypothesis that iron uptake from aerated soils depends primarily on contacts between root surfaces and iron‐bearing soil particles.

Differences in iron uptake not accounted for by root size are described in terms of “root efficiency”, expressed as µg of leaf iron per gram of roots. Addition of CaCO3 to the soil markedly reduced the efficiency of sweet orange roots but affected that of sour orange roots only slightly, which suggests that the transfer of iron from soil to root involves two or more mechanisms that are differentially sensitive to CaCO3.

Sufficiency of iron supply to the plants was correlated with root: top ratio (r = .73 when water suction was varied; r = .72 when both soil CaCO3 and rootstocks were varied). It is concluded that physical dimensions of the iron source (roots) and sink (tops) are important plant factors that regulate iron sufficiency in the plant.
Influence of Tillage Practices on Safflower (Carthamus tinctorius L.) Yields1
Authors: Robison L. R. , Fenster C. R.
Published: July 2010

An experiment to investigate seedbed preparation and planting methods for safflower was conducted from 1963 through 1965. Three tillage intensities, designated excessive, moderate, and minimum depending on the number and kind of tillage operations performed prior to planting, were used.

Three different tillage tools were used as the primary implement in preparing the seedbed — sweep machine, one‐way, and plow. Two different types of drill were used: one with a double rolling disk furrow opener and the other with a planting shoe opener.

Minimumm, oderate, and excessive tillage plot yields averaged 462, 419, and 383 kg/ha, respectively. Yields of 459, 397, and 383 kg/ha of safflower were obtained from sweep‐machine, plow, and oneway plots, respectively. Shoe‐drill plots averaged 455 kg/ha, disk‐drill plots averaged 387 kg/ha, and in only rare instances did the diskdrill equal or exceed shoe‐drill plot yields. Sweep‐machine, minimum tillage plots seeded with the shoe drill gave 336 kg/ha greater safflower yields than commercial fields in the 3 years of the test and 25% better yields than the next highest plot yields in the test. Implements used to produce these yields are common items in farmers' equipmenbt but are seldom used for this crop. In addition, the use of minimum tillage would leave crop residue on the soil surface to help prevent wind erosion and conserve moisture.
Effect of Seed Pod and Temperature on Speed of Germination and Seedling Elongation of Sainfoin (Onobrychis viciaefolia Scop.)1
Authors: Carleton A. E. , Cooper C. S. , Wiesner L. E.
Published: July 2010

Optimum temperatures for germination of sainfoin seed and for seedling growth were determined in conjunction with studies of the effect of the presence or absence of the seed pod. Optimum temperature range for germination of sainfoin was from l5 to 20 C. A higher range of optimum temperature, 20 to 30 C, was found for seedling growth. The presence of pods at all temperatures reduced speed of germination and speed of seedling elongation. Pods on the seed slowed water absorption by 4 to 5 hr. A water soluble inhibitor which slowed the speed of germination of shelled seed was detected. This inhibitor was readily removed from the pod by washing. Mechanical restriction of germination by the pod appeared to be a minor factor in the total effect of the pod on speed of germination. There was no difference in field emergence rates of sainfoin seedlings from shelled and unshelled seed.
Floral Differentiation in Sugarcane and the Subsequent Rate of Development of the Differentiated Tissues1
Authors: Tanimoto T. T.
Published: July 2010

Evidence is presented that floral buds initiate within a 10‐day period beginning about September 7 in sugarcane variety ‘H37‐1933’ (a complex interspecific hybrid involving Saccharum officinarum L., S. spontaneum L., and S. robustum Brandes & Jeswiet ex Grassl), and that the photoperiod of that 10‐day period dictates time of initiation of the flower bud in H37‐1933. The rate of development of these buds and the final emergence of the tassels depend on the strength of the flowering stimulus, which can vary in stalks growing side by side. The top tissues of stalks with early tassels differ morphologically from top tissues of stalks with late tassels or with tassel buds that never emerge.
Effect of a Systemic Insecticide on Forage and Grain Production of Wheat, Barley, Oat, and Rye Varieties1
Authors: Stanley W. W. , Qualset C. O.
Published: July 2010

In experiments conducted at four locations for 2 years, soil applications at time of planting of 10% granules of the systemic insecticide disulfoton at the rate of 11.2 kg/ha had no effect on stand establishment of varieties of wheat, barley, rye, and oats.

Disulfoton treatment caused an increase in fall forage production of ‘Dayton’ barley, ‘Knox 62’ wheat, and possibly ‘Balbo’ rye, but no effect was found for ‘Kenbar’ barley, ‘Monoii‘ wheat, or ‘Blount,‘ ‘Forkedeer,‘ and ‘Le Conte‘ oats.

Disulfoton application had no effect on spring forage production, but grain yields were reduced in 26 of 37 comparisons for all crops. The reduction in grain yields were reduced In 26 of 37 comparisons for all crops. The reduction in grain yield was significant for Knox 62 wheat and Dayton and Kenbar barley. In treatments where no forage was harvested similar reductions in grain yield were found.
Emergence and Development of Sweet Corn as Influenced by Various Soil Mulches1
Authors: Miller D. E.
Published: July 2010

An evaluation was made of the influence of three mulches on early development and maturity of sweet corn. The mulches were: (a) a film of water emulsion asphalt sprayed over the seeded row; (b) plates standard greenhouse glass between seeded rows; and (c) a layer of water contained in polyethylene bags between seeded rows. Early spring soil temperatures were increased by the mulches. Emergence of seedlings and plant developmentw ere also hastened. Sweet corn planted April 6 was ready for harvest on glass.mulched plots 13 days earlier than on nonmulched plots. Asphalt and water mulches resulted in harvest 7 and 3 days earlier than from nonmulched plots. Combining early seeding (April 6) with mulching resulted in sweet corn harvests 19, 13, and 9 days earlier than normal seeding time (early May) in the bare soil for glass, asphalt, and water mulches, respectively.
Timing of Nitrogen Fertilization of Rice. II. Culm Elongation as a Guide to Optimum Timing of Applications Near Midseason1
Authors: Hall V. L. , Sims J. L. , Johnston T. H.
Published: July 2010

Field studies were conducted with ‘Vegold,’ ‘Nato,’ and ‘Bluebonnet 50’ rice (Oryza sativa L.) in 1963, 1964, and 1965 to determine the optimum time near midseason to apply nitrogen fertilizer for greatest yield. Internode elongation was used as a guide to estimate proper morphological stage of development for the optimum time to apply nitrogen.

During the 3 years of study all three varieties had grain yield increases of over 1,120 kg/ha that could be attributed to applying midseason nitrogen at the proper time during panicle initiation. Topdressing nitrogen at midseason was found to be most effective when 50% of the plants had elongating internodes equal to or in excess of 12.8 mm for Vegold, 39.7 mm for Nato, and 32.1 mm for Bluebonnet 50.
Residue Placement Effects on Decomposition, Evaporation, and Soil Moisture Distribution1
Authors: Unger Paul W. , Parker J. J.
Published: July 2010

In a greenhouse study, wheat (Triticum aestivum L.) residue placement affected residue decomposition, evaporation, soil moisture distribution, pH, and nitrate‐N content. Residues mixed with or covered by soil decomposed at similar rates, but surface residues did not decompose measurably. Surface and covered residue treatments, compared with the mixed residue treatments, reduced evaporation 57.4 and 18.9%, respectively. When approximately 60% of plant available moisture remained in the soil, moisture contents decreased with soil depth below the residue layer for surface and covered residue treatment. For the mixed residue treatment, soil moisture content initially increased with depth, then decreased. Soil pH remained relatively high for mixed and covered residue treatments, but decreased for the surface residue treatment.

No differences in decomposition, evaporation, or soil moisture distribution were noted due to rate of N or sulfur application. Soil pH was lowered by the high N application rate and was significantly correlated with soil nitrate‐N content. Applied sulfur did not affect pH.
Collapse of Alfalfa Petioles Their Calcium Content1
Authors: Nightingale H. I. , Smith R. L.
Published: July 2010

Alfalfa (Medicago sativa L.) plants were grown in a series of reduced calcium nutrient solutions which ranged from 1.9 to 80.0 mg Ca per liter after the plants were established using a complete nutrient solution. A sudden collapse of alfalfa petioles occurred most frequently when the calcium content of the shoots was between 11 and 16 meq per 100 g. Petiole collapse rarely occurred when the calcium content of the shoots was less than 11 meq or greater than 30 meq per 100 g dry weight. Chemical analysis of normal petiole sections showed an increase in calcium content as the leaf was approached. However, in abnormal (collapsed) petioles the reverse was found.
Tillage‐Soil Water Relations of Corn as Influenced by Weather1
Authors: Amemiya M.
Published: July 2010

Crop responses to tillage methods in the Corn Belt frequently vary among years and locations. Experiments on corn (Zea mays L.) conducted in Iowa during 1956‐66 indicate that the effectiveness of tillage methods is associated with weather and consequent soil water conditions. On Moody silt loam, in northwestern Iowa, severe soil water deficits occurred in 6 of the 11 years. In these years, lister‐planted corn outyielded conventionally planted (plow‐disk‐harrow) corn by as much as 2,588 kg/ha (41.2 bu/acre). Intermediate crop responses were obtained from other tillage methods, which included wheel‐track planting, mulch tillage, ridge planting, and cultivator planting. Crop responses were related to differences in soil water regime attributed to tillage. Under favorable weather and soil water situations, there was little difference among the several treatments.
Agronomic Factors Affecting Polonium‐210 and Lead‐210 Levels in Tobacco. I. Soil and Fertilizer
Authors: Tso T. C. , Steffens G. L. , Ferri E. S. , Baratta E. J.
Published: July 2010

An examination of soils from tobacco‐producing areas and fertilizers commercially available for tobacco production revealed that a wide variation in the levels of Ra220, Pb210 and Po210 exists in those samples. Cultural practices and source of fertilizer may contribute to these variations. Radioelements from fertilizer used for one growing season may not affect the level of these elements in the immediate crop, but will contribute to the buildup of the radioisotope level in the soil.
Nutrient Distribution During Development of Three Market Types of Peanuts. I. P, K, Ca, and Mg Contents1
Authors: Hallock D. L. , Martens D. C. , Alexander M. W.
Published: July 2010

Six plant portions of each of three peanut (Arachis hypogea L.) cultivars representing the three market types were sampled on four dates. Many interactions occurred for each nutrient among the 'cultivars, plant portions, and sampling dates.

The highest P(0.35%) and K(3.7%) contents in the cultivars were in the July 12 and October 10 leaf‐samples, respectively, of the first lateral branches of ‘Virginia 61R’. Also, similar portions of Virginia 61R sampled in July and August were high in K. Highest Ca (1.8%) and Mg (0.7%) contents were in the June 16 and October 10 samples of the second lateral branch‐leaves and upper main stem (principally leaves) portions, respectively, of ‘Starr’. Nutrient contents in the ‘Early Runner’ portions generally were intermediate or similar to the cultivar having the lowest average contents.

P, K, Ca, and Mg contents in the July main stem portion were statistically similar to or only slightly lower than in other leafy portions sampled on June 10, August 31, or October 10. Contents of the nutrients except Mg in June in the first and second lateral branch‐stems usually were lower than in the leafy portions, but higher than in the hypocotyl‐crown portion. P contents of the fruit samples were considerably higher, whereas K and Ca levels were markedly lower than in the other portions sampled on similar dates.
Variable Row Spacing of Irrigated Cotton as a Means for Reducing Production Costs and Conserving Water
Authors: Longenecker D. E. , Thaxton E. L. , Lyerly P. J.
Published: July 2010

Results of 3 years' field studies of a new irrigated cotton row spacing pattern are reported. This new pattern, called Variable Row Spacing (V.R.S.), consisted of alternate wide (1.37 m) and narrow (0.66 m) rows with furrows only between the 0.66‐m rows. Purpose of the new pattern was to conserve water and reduce production costs. Tests on both sloping and level irrigation systems are reported. The V.R.S. system was shown to be effective in maintaining yields while simultaneously presenting opportunity for reducing production costs through application of less water per irrigation, reductions in evaporation, more efficient utilization of applied water, more effective weed control, and earlier maturity of the crop. A partial skip‐row effect was believed to be obtained without skipping any rows. Chief obstacle to adoption of the new system by growers has been inability of commercial spindle pickers to harvest the variable row spacing pattern.
Residual Effect of Feeding Grain to Grazing Steers upon the Productivity of Pasture1
Authors: Benacchio S. S. , Mott G. O. , Huber D. A. , Baumgardner M. F.
Published: July 2010

A grazing trial was conducted during the growing season of 1967 to study the residual effect upon pasture productivity of 4 years of feeding different levels of grain to grazing steers. The effect on the pasture was measured in terms of steer days/ha estimated total digestible nutrients (ETDN) consumed/ha, forage dry matter produced/ha, and crude protein composition of the herbage. Each increase of 10 metric tons of grain fed per hectare increased the carrying capacity of the pastures, 53 steer days; the estimated total digestible nutrients consumed, 145 kg; and the forage dry matter yield, 224 kg. The increase in crude protein produced per hectare was 19 kg for each 10‐ton increment of grain fed.
Effect of Nitrogen, Phosphorus and Zinc Placement on Yield and Composition of Potatoes1
Authors: Soltanpour Parviz N.
Published: July 2010

Field experiments showed that the method of placement of fertilizers was crucial for potato production. Uptake of N, P, and Zn, when these nutrients were broadcast and disked, was not significantly different from the uptake when no fertilizer was applied to the soil under furrow‐irrigation and the semi‐arid conditions of the San Luis Valley of Colorado. Banding proved to be a more efficient method of applying fertilizers to potatoes.

Nitrogen increased P and Zn uptake. Phosphorus reduced Zn uptake and Zn reduced P uptake. Application of P and Zn in separate bands in the soil did not seem to reduce the antagonistic interactions between these two elements.
The “Donnan Theory” in Development of Plant Growth Media from Ion‐Exchange Resins1
Authors: Skogley Earl O.
Published: July 2010

Synthetic ion‐exchange resins were prepared to serve as plant growth media. The resin was considered as an exchanger phase present for the purpose of controlling the solution phase composition within a range known to be satisfactory for plant growth. The “Donnan Theory”, an assumed Ca++ concentration of the solution phase based on the carbonate equilibrium, and known desirable solution phase concentrations were employed for determination of resin treatments. Treatment variables were introduced to test the functioning of the “Donnan System” in the resin media. The exchanger and solution phases of prepared media were separated and analyzed. Although differences were found between theoretical and experimental values, the data are considered to support the functioning of the system. Uncertainties due to unknown activity coefficients and lack of proved procedures are considered responsible for the observed discrepancies.

Wheat (Triticum vulgare, L.), tomato (Lycopersicon esculentum, Mill.), and sunflower (Helianthus annuus, L.) were grown in the resin media, in a fertilized mixture, and in nutrient solutions. Plant yields were about equal from resin media and soils, but much less from nutrient solutions. The cation nutrient composition, including micro‐nutrients, of plants grown in resin media was essentially the same as in soil‐grown plants.
Colorimetric Determination of Protein in Feed and Forage Crops1
Authors: MacKenzie Arnold J. , Perrier Eugene R.
Published: July 2010

A colorimetric method using Orange G dye for the determination of protein in feed and forage crops is described. With each of six crops tested, a good correlation was found between Kjeldahl nitrogen percentage and the dye‐binding characteristics of the plant proteins. The method is reproducible, rapid and easily adapted to a simplified routine operation.
A Rapid Method of Determining the Hull Content of Safflower and Sunflower Seeds
Authors: Nur Idris Mohmd
Published: July 2010

Five safflower varieties and five sunflower varieties were subjected to three methods of hull determination. The standard method of germinating the seed in distilled water was compared with two other methods: germinating the seed in hydrogen peroxide and using a seed‐cutter manufactured locally.

The seed‐cutter technique for hull determination was found to be rapid and accurate for safflower and sunflower seeds.

Samples containing 45 seeds for safflower and 35 seeds for sunflower were found to be adequate.
Availability Characteristics Of and Plant Response to Nitrogen Sources
Authors: McCants C. B.
Published: July 2010

The relative availability characteristics of nitrogen in urea, cottonseed meal, a commercial urea‐formaldehyde product, and an experimental urea‐wax material were studied through successive leachings in model lysimeters in the laboratory and by leaching and plant growth in the greenhouse. The effects of the nitrogen sources on yield and chemical composition of field‐grown tobacco were studied under different moisture regimes.

The total release of nitrogen from the urea‐wax source was comparable to that from urea but significantly higher than from urea‐formaldehyde or cottonseed meal sources. The rate of N release during the first 21 days was not different among the urea‐wax, urea‐formaldehyde, and cottonseed meal sources; thereafter, it was higher from urea‐wax. When differences in crop response occurred among the different sources, the yield and quality index were higher from urea‐wax than from cottonseed meal or urea‐formaldehyde. These results and data from other research suggest that the probability of practical contributions of slow release fertilizers in the commercial production of annual field crops is quite small.
Effect of Planting Dates on the Incidence and Severity of Corn Virus Diseases1
Authors: Keaster Armon J. , Zuber M. S. , Fairchild M. L. , Loesch P. J.
Published: July 2010

A date‐of‐planting study was conducted in southeast Missouri near Portageville, for a 3‐year period, to determine the effect of planting date on the incidence and severity of certain symptoms reported to be associated with maize dwarf mosaic or corn stunt. The study included 12 hybrids having varying degrees of tolerance to these diseases and differing in maturity. Throughout the 3‐year period, the disease incidence or severity ratings increased with each delay in planting. In addition, differences among hybrids and the interactions of planting dates by hybrids were statistically significant.
Effect of Irrigation and Clipping on Seed Production and Chasmogamy of Sericea Genotypes1
Authors: Donnelly E. D. , Patterson R. M.
Published: July 2010

Seed yield and proportion of chasmogamou seed as affected by irrigation and clipping were determined for 18 lines of sericea, Lespedeza cuneata. Seed yields were increased by irrigation regardless of clipping management; however, irrigation did not increase the percentage of chasmogamous seed. Clipping in June drastically reduced seed yield and percentage chasmogamous seed. Irrigation of clipped sericea further reduced chasmogamous seed percentage below that of nonirrigated clipped sericea. Lines reacted differently to irrigation and clipping both as to proportion of seed types and seed yield.
Factors Affecting Plant Growth in High‐Zinc Medium: II. Influence of Soil Treatments on Growth of Soybeans on Strongly Acid Soil Containing Zinc from Peach Sprays1
Authors: Lee C. R. , Craddock G. R.
Published: July 2010

A field experiment was conducted to study the influence of soil pH micronutrient additions and other management practices on soybean yields where peach trees had been grown previously. Decreased soybean yields resulted when either zinc sulfate or superphosphate was added to soil with a pH value below approximately 5.40. FeEDDHA improved plant growth, but did not influence soybean yields. Raising soil pH from 5.40 to approximately 6.40 with 2,602 kg/ha of dolomitic limestone increased plant growth and soybean yields. Zinc content of leaves ranged from a high of 229 ppm in acid soil to 77 ppm in limed soil. Highest soybean yields were obtained from organic matter (snap corn meal) in combination with dolomitic limestone.
Form and Availability of P in Selected Virginia Soils as Related to Available P Tests1
Authors: Martens D. C. , Lutz J. A. , Jones G. D.
Published: July 2010

Relationships among inorganic P fractions, P extracted by the acid fluoride (Bray no. 1), and dilute acid (Mehlich) soil tests, and the P supplying power of Davidson clay loam, Groseclose and Nason silt loams, and Wellston fine sandy loam were evaluated by correlation and regression analyses. The soils under study contained wide ranges in contents of inorganic P fractions and of P extracted by the soil tests due to application of various amounts of different P sources during long‐term field investigations. Correlation analyses indicated that P from the A1 phosphate fraction was the main source of P to oat plants (Avena saliva L. ‘Andrew’) grown in the greenhouse on the four soils.

Statistical data showed that P from the AI phosphate fraction was the predominant source of P extracted from each of the four soils by the acid fluoride soil test. Similar data indicated that the dilute acid soil test extracted P from mainly Ca phosphate in the Nason and Wellston soils and from A1 phosphate in the Groseclose soil. The close relationship between dilute acid extractable P and Ca phosphate in the Nason silt loam and Wellston fine sandy loam was explained as extraction of P from rock phosphate which had been applied to the soils during long‐term field investigations. Phosphorus extracted by the dilute acid soil test was not closely related to any of the inorganic P fractions in the Davidson clay loam.

Acid fluoride extractable P was more closely related than dilute acid extractable P to P uptake from each soil, except the Groseclose silt loam. Phosphorus extracted by both soil tests was equally related to P uptake from the Groseclose soil. The acid fluoride extractable P contents required to attain maximum yield was inversely related to the clay contents of the Davidson, Groseclose, and Wellston soils.
Applicator for Broadcasting Dry Fertilizer on Experiment Plots1
Authors: Robertson Wendell , Beason Windel C. , Onken Arthur B.
Published: July 2010

An attachment for broadcasting granular materials from multiple‐cell, belt type fertilizer distributors is described. This equipment is economical and does not limit equipment use for banding granular materials.
Ammonia Volatilization from Ratios of Formamide and Urea Solutions in Soils1
Authors: Loftis J. R. , Scarsbrook C. E.
Published: July 2010

Ammonia volatilization from soils treated in the surface 1½ cm with mixtures of formamide and urea (F:U) was measured in laboratory incubation experiments. Norfolk sandy loam, which had a cation exchange capacity (CEC) of 3.7 meq/100 g and an initial pH of 5.9, evolved 18.5% at the highest rate of applied N. Losses of N from Boswell fine sandy loam, which had a CEC of 13 meq/100 g and an initial pH of 5.8, was 13.0%. Sumter clay, which had a CEC of 33 mg/100 g and an initial pH of 7.8, gave negligible losses. Urea was nitrified at approximately twice the rate of formamide in Sumter clay, but rates were low and similar in Norfolk and Boswell soils. There was a larger percentage loss of NH3 at the high N rates than at the lower rates. Addition of Ca(OH)2 increased losses of NH3 on Norfolk soil. All F: Uratios increased the soil pH alike and the rate of application determined the magnitude of the increase. Increasing the F:U generally had no effect on NH3 losses. The results showed a large positive relationship between NH3 loss and the final soil pH of Norfolk, but the effect was smaller on Boswell.
Effect of Full and Restricted Sun Exposure on Curing Peanuts1
Authors: Mixon Aubrey C. , Mott Paul A.
Published: July 2010

Green peanut pods considered to be at optimum maturity from peanut plants, Arachis hypogaea L. ‘Early Runner,’ were exposed to available and restricted sunlight until dried to 20, 15, 12, 9, or 7% seed moisture. Samples removed from sun exposures with seed moisture higher than 7% were dried to 7% average seed moisture in ambient‐air forced‐draft drying bins. Treatments were stored in closed containers at 75% relative humidity for 3 months before processing. The full‐sun exposure treatment reduced germination of sound mature seed 1 year, and germination of sound immature seed all 3 years compared with restricted (50%) sun exposure. Exposure of pods to full sunlight reduced promptness with which both mature and immature seed germinated in a 25 C germinator. Greatest reduction in promptness of germination and total germination occurred in immature seed from the fully exposed pods. Each year the percentage of seed breakage upon shelling was greater for peanuts in available sun than for those in restricted sun treatments. In 2 out of 3 years, drying peanuts to 9 or 7% seed moisture, in available sun, resulted in a less desirable flavor of roasted ground, mature seed than of those dried to 20% moisture in full sun and then dried to 7% moisture in ambient air.
Legume Contributions to Yields and Compositions of Desmodium Spp.‐Pangolagrass Mixtures1
Authors: Whitney A. S. , Green R. E.
Published: July 2010

A field experiment on a Humic Latosol at 640‐m elevation compared pure pangolagrass (Digitaria decumbens) and mixtures of (a) pangolagrass plus uninoculated Desmodium canum, (b) same but inoculated, (c) pangolagrass plus D. intortum in 90 cm rows, and (d) same as (c) but D. intortum in 45 cm rows. All treatments were tested under limed and unlimed conditions. Dry matter yields over a 2‐year period averaged: pure pangolagrass 3,780, (a) 6,840, (b) 7,510, (c) 10,810, and (d) 11,960 kg ha‐1 yr‐1. Percentage legume was low in (a) and (b), and over 50% in (c) and (d). Percentage crude protein was also highest in (c) and (d). The CP yields of the mixtures were approximately equivalent to pure pangolagrass fertilized with N (as (NH4)2SO4) at the following rates: (a) 210, (b) 240, (c) 440, and (d) 525 kg N ha‐1 yr‐1.

Apparent N‐fixation in (b) was 97 kg ha‐1 yr‐1, and inoculation of D. canum [(b) — (a)] gave a nonsignificant benefit of approximately 17 kg N ha‐1 yr‐1. D. intortum fixed approximately 213 kg ha‐1 yr‐1 in (c) and 264 kg in (d). The total amount of fixed N transferred to the grass was higher for D. intortum, but a higher percentage of the fixed N was transferred from D. canum.

There were wide seasonal variations in dry matter yields and percentage crude protein, but the ranking of the treatments was quite consistent throughout the 2‐year period for both of these characteristics. D. canum growth was reduced at average night temperatures below 16 C while D. intortum was affected little until average night temperatures fell below 15 C.

There was no benefit for liming in any of the treatments. Yields of D. intortum were depressed when exchangeable potassium was approximately ≤ 0.1 meq/100 g of soil.
Growth of Young Orchardgrass (Dactylis glomerata L.) Plants in Different Environments1
Authors: Templeton W. C. , Menees J. L. , Taylor T. H.
Published: July 2010

Growth and development of young ‘Boone’ orchardgrass plants were studied in a factorial experiment involving two temperature regimes, two photoperiods, three levels of N, and four levels of P. Seed was planted in a growth medium of Hartsells fsl soil and washed sand. Three days after emergence, seedlings were subjected to the experimental temperatures and photoperiods. Harvests of whole plants were made 3 weeks after the temperature‐photoperiod treatments were initiated and at 2‐week intervals through the eleventh week. Photoperiod effects were evident at the first harvest. With essentially equal radiant energy supplied to the two groups, the leaves of plants in the shorter, 10‐hour, photoperiod (SD) emerged more rapidly. Also, SD plants had a greater total length of exposed leaf blades during the early weeks and a lower shoot: root ratio than did plants in the 20‐ hour photoperiod. Weights of shoots, roots, and whole plants were greater under SD during the first 7 weeks. No response to supplemental N was detected during the first few weeks, but later it increased rate of leaf appearance, length of exposed blades, and weights of shoots and roots. With all measurements, marked responses to P were obtained. For the most part, interactions were relatively unimportant, but a strong N × P effect was operative after the 5th week. It is concluded that the observed plant‐weight increases may be accounted for, in part, by the morphological responses and their effects on light interception and absorptive capacities of the root systems.
Root Development and Phosphorus Uptake by Tomato Plants under Controlled Soil Moisture Conditions
Authors: Thorup Richard M.
Published: July 2010

The effect of soil moisture tension upon root growth and phosphorus uptake by tomato plants was studied using a split‐root technique. Root systems were developed in soil maintained at three different moisture levels—one well below PWP, another slightly below PWP, and a third within the “available” range. Root growth was very restricted at the lowest level of soil moisture—attaining a maximum length of 20 mm. At the level slightly below PWP, roots grew to a length of 90 mm, with substantial secondary root development. Maximum growth was attained at the moisture level maintained above PWP. At this level roots reached a length of 150 mm and exhibited extensive secondary branching.

Phosphorus uptake was measured by use of radioactive P. At all three moisture levels phosphorus was taken up by the plants. A significant increase in uptake accompanied each increase in soil moisture.

Moisture was transferred through the plant root system from zones of low tension to zones of high tension within the soil.
Effect of Ethrel on Growth and Yield of Corn
Authors: Earley E. B. , Slife F. W.
Published: July 2010

Ethrel sprayed on corn plants at three rates and at several stages of development caused a reduction in plant height, leaf area, leaf efficiency, and yield of grain as compared to untreated plants. No beneficial effects were observed from the use of this chemical on corn under the conditions of this experiment.
Influence of Photoperiod on Flowring of Rumex Crispus L.1
Authors: Maun M. A. , Cavers P. B.
Published: July 2010

Seed production and height of plants of curled dock (Rumex crispus L.) were at a maximum under a 15‐hour daylength. Flowering was greatly delayed but not prevented by shorter photoperiods of 8 and 12 hours. Seed weight and viability were not affected by any treatment.
Yield and Concentration of Meadow Hay Fertilized with Three N Sources
Authors: Rumburg C. B.
Published: July 2010

Meadow hay from plots fertilized with anhydrous ammonia in the spring prior to or during flooding ranged from .15 to .25% higher in nitrogen concentration than hay from plots fertilized with broadcast applications of ammonium sulfate or urea. Hay yields from plots fertilized with anhydrous ammonia in the spring were similar to yields from plots fertilized with ammonium sulfate or urea except that yields from plots fertilized with anhydrous ammonia were significantly higher in two experiments. Fall applied anhydrous ammonia was similar to fall or spring applied ammonium sulfate.