bluuebunny/crossref_metadata_2025_split huggingface dataset:
Influence of Cool and Warm Temperatures and Temperature Reversal at Inflorescence Emergence on Growth of Timothy, Orchardgrass, and Tall Fescue1
Authors: Knievel D. P. , Smith Dale 
Published: July 2010

AbstractTimothy (Phleum pratense L.), orchardgrass (Dactylis glomerata L.), and tall fescue (Festuca arundinacea Schreb.) were grown from small propogules in pots of soil in growth chambers to evaluate the effect of temperature and temperature change on flowering, tillering, dry matter accumulation and distribution, and leaf‐blade area accumulation within and among species.Temperature greatly influenced maturation rate, growth rate, yield, tillering, leaf‐blade area, specific leaf‐blade weight (SLW), and dry matter (DM) distribution within each species. Except for maturation rate and DM distribution, each parameter was highest for all three species in cool (C, 18 C day/10 C night) or warm‐cool (WC, 32 day/24 C night with a change to 18 C day/10 C night at early inflorescence emergence) temperature regimes. Flowering in timothy was not affected by temperature. Significantly fewer flowering culms were obtained in orchardgrass at warm (W, 32 C day/24 C night) compared with C temperatures, while the opposite was true in tall fescue. Late anthesis in each of the grasses occurred first in the W regime and last in the C regime. Maturation rate, after switching from cool to warm (CW, 18 C day/ 10 C night with a change to 32 C day/24 C night at early inflorescence emergence) or warm to cool temperatures (WC) at early inflorescence emergence, varied among the three species. Timothy had the largest increase in maturation rate following the change from C to W temperatures, while that of tall fescue was least affected by the temperature change. Influence of temperature regimes on DM distribution among plant parts varied among species. Timothy was most sensitive to changes from C to W temperatures, while tall fescue was least sensitive. Warm temperatures slowed leaf‐blade area accumulation in orchardgrass and tall fescue in the CW regime and completely stopped it in timothy. Cool temperatures in the WC regimes stimulated leaf‐blade area accumulation in all three grasses. SLW of all three grasses increased with growth stage. Tall fescue had the highest SLW averaged over temperatures and growth stages, followed by orchardgrass and timothy. Change in temperature in the CW regime was followed by a decrease in SLW in each species compared with the C regime, while the opposite was true in the WC compared with the W regime. Timothy, followed in order by tall fescue and orchardgrass, produced the most DM in the C, CW, and WC regimes. Orchardgrass and tall fescue had similar DM yields which were higher than timothy in the W regime. Dry matter accumulation (DMA) rates in corresponding temperatures regimes were similar among species.It was concluded that the grasses differed in growth and development response to temperature and in sensitivity to temperature change. Differences in total plant yield among the three grasses in comparative temperature regimes were due to differences in DMA rates and in length of growth period.
Effect of Pretransplant Lighting on Post‐transplant Growth and Development of Tobacco1
Authors: Kasperbauer M. J. 
Published: July 2010

AbstractUniformity in time of flowering is desirable in tobacco (Nicotiana tabacum L.) production, especially when mechanization is involved. This study was initiated to determine methods of controlling premature floral induction without causing undesirable side‐effects to the plants. Burley tobacco seedlings were treated with various combinations of illumination during the pretransplant period in controlled‐environment chambers and outdoors in modified starting beds. Effectiveness of control was assayed under field conditions.Early floral induction occurred in seedlings that received high intensity short days and cool temperatures, or low intensity natural daylengths coupled with cool temperatures. When 12‐minute middle‐of‐night interruptions were used, white fluorescent light was more effective than white incandescent light in counteracting a florally inductive environment, while incandescent was slightly more effective than fluorescent when 240‐minute interruptions were used. Twelve minutes of white incandescent light applied in 30‐second increments repeated each 10 minutes during a 240‐minute period were almost as effective as 240 minutes of continuous illumination from the same type of lamps. Night interruptions with white and yellow incandescent light were equally effective. Phytochrome involvement in counteraction of floral induction in tobacco was discussed.Pretransplant treatments that showed most promise in the controlled‐environments were tested over outdoor starting beds in 1970 and 1971. The first year had a period of cool overcast weather during the treatment period, and the middle‐of‐night supplemental lighting was effective in delaying floral induction. Bright, warm days predominated during the 1971 treatment period, and no premature flowering occurred among either the controls or the treated plants. There were no undesirable sideeffects of the supplemental lighting during either year.In general, plants that flowered prematurely developed fewer leaves prior to flowering, produced several suckers per plant, were difficult to harvest, and yield of cured leaf was significantly reduced.
Influence of Inoculum Size on Rhizobium japonicum Serogroup Distribution Frequency in Soybean Nodules1
Authors: Kapusta George , Rouwenhorst D. L. 
Published: July 2010

AbstractInvestigations were conducted in 1969 and 1970 to determine the influence of ultra‐high inoculation rates of a single Rhizobium japonicum strain on recovery from soybean (Glycine max (L.) Merr.) nodules. Biological seed yield, nodule mass, seed oil, and protein also were studied. Bacterial suspensions containing up to 1.2 × 1012 rhizobia per cm of row were banded in contact with the seed during planting. A rapid agglutination test was used to distinguish R. japonicum serogroups in homogenized nodule suspensions. Strains 138 and 126 were used as the inoculum in 1969 and 1970, respectively.Control plot rhizosphere R. japonicum population was between 30,000 and 300,000 per g of oven‐dried soil. The predominant naturalized serogroups in these plots were 123 and c‐1(138) in 1969 and 1970, respectively, despite a distance of only 300 m between test areas. Strain 138 recovery percentage in 1969 increased from 18% in the uninoculated plots to 60% in plots receiving 15 billion rhizobia per cm of row. Similar significant shifts occurred in 1970. The data indicate that it is possible to evoke shifts with at least two serogroups. If superior strains are developed in the future, this technique would be one way to establish them rapidly.Nodulation, plant growth characteristics, seed yield, and oil and protein content were not influenced by the inoculum rates with one exception. Biological yield was significantly increased in 1970 at the highest inoculum rate. The reason for this observation is not readily apparent.
Double Cropping Systems Involving No‐Tillage and Conventional Tillage1
Authors: Sanford J. O. , Myhre D. L. , Merwine Norman C. 
Published: July 2010

AbstractThis study was prompted by the huge feed grain deficits which increase annually in the Southeast. The need exists to find ways of increasing grain production efficiently. Cropping‐tillage systems designed to accomplish this were studied. Soybeans [Glycine max (L.) Merr.] and grain sorghum [Sorghum bicolor (L.) Moench.] were double cropped following wheat (Triticum aestivum L.) on a Blackbelt soil. No‐tillage and conventional tillage methods were compared for soybeans and grain sorghum; Conventional tillage was used for wheat.The 2‐year average yield of soybeans was 1,708 kg/ha (25.4 bu/acre) for no‐tillage and 2,250 kg/ha (33.4 acre) for conventional tillage. This difference was significant (P = .05) and was due mainly to lack of nutsedge (Cyperus sp.) control by herbicide alone in no‐tillage plots. In the third year when the crop was hand‐hoed, no yield differences occurred due to tillage methods. The 2‐year average yield of grain sorghum was 3,249 kg/ha (48.3 bu/acre) for no‐tillage and 3,868 kg/ha (57.5 bu/acre) for conventional tillage. When the crop was handhoed yield of grain sorghum was significantly higher for no‐tillage (5,072 vs 4.335 kg/ha). Wheat grown after soybeans yielded significantly (P = .05) more than wheat grown after grain sorghum. This difference was attributed primarily to the bneficial effect of residual N from the previous crop of soybeans.Based on current costs and prices, the soybean‐wheat double cropping system produced significantly higher net returns over specified production costs than the wheat. grain sorghum system.
Establishment Methods for Alfalfa in Irrigated Corn1
Authors: Nordquist P. T. , Wicks G. A. 
Published: July 2010

AbstractEstablishing alfalfa (Medicago sativa L.) under irrigation is expensive and production is low during the establishment year. Our objective was to determine, in the absence of moisture stress and weed competition, which combinations of corn (Zea mays L.) types and alfalfa planting dates would be most productive during the year of planting and the year following establishment. Alfalfa was planted at corn planting time, at last corn cultivation, or after the harvesting of corn for silage. Weed control was obtained by cultivation or using 4‐(2,4‐dichlorophenoxy)butyric acid (2,4‐DB), 2,2‐dichloropropionic acid (dalapon) or S‐ethyl dipropylthiocarbamate (EPTC) without cultivation. Alfalfa stand and yield were increased 27 and 9%, respectively, when alfalfa was planted simultaneously with the corn and the corn harvested as silage; however, this planting method reduced corn silage production from 20 to nearly 50% and grain yields from 1,000 to 3,000 kg/ha compared to alfalfa planted at last cultivation or following silage harvest. Generally ‘Brachytic dwarf’ corn was a poor competitor to alfalfa. Full‐season and midseason hybrids had about the same silage yields, but the full‐season hybrid produced more corn. Under the conditions of our experiment, a midseason corn hybrid planted at 59,000 seeds/ ha, with corn and alfalfa planted at the same time and corn harvested as silage, proved to be an excellent establishment method. This combination gave high silage yields, and removing the corn crop permitted good fall growth of the alfalfa.
Flue‐cured Tobaccos With Varied Ripening Pattern for Modified Harvest Systems1
Authors: Chaplin James F. 
Published: July 2010

AbstractMechanically harvesting flue‐cured tobacco (Nicotiana tabacum L.) requires uniform ripening of leaves. Tobaccos are available with varied ripening patterns and a test was conducted to determine which may be more adaptive to varied harvesting systems. Flue‐cured cultivars ‘Coker 139’ and ‘NC 95’ and a pale yellow hybrid were used. These tobaccos varied in ripening patterns, total alkaloids, and reducing sugars. Harvest systems used were conventional, twice‐over, and once‐over for 61 cm and 115 to 140 cm (normal) topping heights. The time of topping was varied in the once‐over harvest systems.All of the modified systems, except when the pale‐yellow hybrid was harvested twice, resulted in reduced yield compared to that of the conventional system. Yields were progressively reduced by the low‐topped treatments as the time of topping was delayed. Plants which were topped normally and had all of the leaves removed at one time produced the most undesirable tobacco; with NC 95 and the pale‐yellow hybrid being the poorest.Total alkaloids were higher in tobacco from the low‐topped, once‐over harvest treatment (except that topped at harvest) than in that produced from the conventionally topped and harvested treatment. However, with a low‐alkaloid cultivar (Coker 139), an acceptable level of total alkaloids was obtained in the low‐topped, once‐over harvested tobacco when the plants were topped early. Cured leaf was produced from some of the low‐topped once‐over harvested treatments, that equalled that produced by conventionally topped and harvested for value per 45.4 kg, total alkaloids, and reducing sugars.
N Fertilization and Yield Response of High Lysine and Normal Barley1
Authors: Andersen A. J. , Køie B. 
Published: July 2010

AbstractThe yield and quality of barley (Hordeum vulgare L.) are greatly influenced by N fertilization. The yield of dry matter, mineral nutrients, and protein are generally increased but the concentration of the essential amino acid lysine in the protein is usually decreased by increasing the supply of N. However, the effect of N may vary between genotypes. The purpose of this study was to compare the response to N of a high‐lysine genotype to that of normal barley.The high‐lysine Risø mutant 1508 and its parent variety ‘Bomi’ were grown in plastic pots containing 22 kg sandy loam (Gray‐Brown Podsolic soil). Nitrogen was supplied as NH4NO3 in amounts of: O, 1, 2, 3, 4, and 6 g N/pot.The yield of dry matter increased with N fertilization up to 3 to 4 g N/pot after which it declined with additional N‐supply, while the yield of protein continued to increase. Lower grain yield of the mutant was almost entirely caused by a smaller grain size. The concentration of lysine in Bomi protein declined when protein production was increased by application of N fertilizer, whereas in the mutant it remained nearly constant. The high‐lysine character was thus enhanced when protein content in the grain was increased. The concentrations of P, Ca, and Mg were higher while that of K was lower in the grain of the mutant 1508 than in the grain of the parent variety Bomi.
Yield and Quality of Corn and Grain Sorghum Grain and Residues as Influenced by N Fertilization1
Authors: Perry L. J. , Olson R. A. 
Published: July 2010

AbstractCrop residues of grain sorghum (Sorghum bicolor (L.) Moench) and corn (Zea mays L.) have attracted attention as an alternate economical forage resource for livestock utilization. There are little data available on agronomic production factors affecting yield and quality of crop residues. We evaluated the effect of rate and time of N fertilization on irrigated corn and grain sorghum grain and residue yields, grain N content, and forage quality of the residues.During 1972 and 1973 irrigated corn and grain sorghum plots were fertilized with O, 90, 180 and 270 kg/ha of N as a 32% N solution at planting or sidedress with two P levels (O and 22 kg/ha) incorporated prior to planting. Grain and residue samples were analyzed for grain N content, and residue crude protein and in vitro dry matter digestibility (IVDMD).Corn grain yields increased significantly with N applied at 90 and 180 kg/ha, while grain sorghum grain yields increased significantly only at the 90 kg/ha rate. Grain N content increased with N fertilization for both crops. Grain sorghum N content was generally equal to or greater than corn. Residue yields of both crops were increased significantly by 90 kg/ha with no further increase at the higher N rate. Corn grain/stover ratios increased with increasing N levels. Crude protein of grain sorghum residues was consistently higher than corn while IVDMD values were consistently lower in grain sorghum. Crude protein increased significantly in grain sorghum residue with each increasing N level while little increase occurred in corn.We conclude that N rate and time of application does affect yield and quality of row crop residues. This would have an affect on supplementation of livestock grazing row crop residues.
Long‐term Residual Fertility and Current N‐P‐K Application Effects on Soybeans1
Authors: Boswell Fred C. , Anderson O. E. 
Published: July 2010

AbstractSoybean (Glycine max L.) yield response to currently applied fertilizers, especially N, has been erratic while responses to residual P and K have been more consistent. This study was conducted to determine if residual N‐P‐K fertilizers applied over a period of years to other nonleguminous crops would influence soybean fertilizer requirements. Soybeans were planted on a Rarden sl soil (Typic Dystrochrept) where plots had received the same rates of P and K for 13 years. Previous N levels were 56 or 112 kg/ha, depending on the crop. Since legumes had not grown on the area for at least 16 years, significant responses to 56 kg/ha of N occurred each year at the high level of P and K. A greater yield response occurred from the P application than from K. The fertilizer × year interaction effects on yield was greatest for P as compared to N or K interactions when fitted to a regression model equation. The highest rates of N‐P‐K resulted in significantly larger soybean seed, better quality (seed index), and higher crude protein content than low N‐P‐K rates or control plots. Crude protein was inversely related to total oil content. Even though relatively high levels of P and K were applied to certain plots for 16 years and crop residues remained on the soil surface each year, high levels of extractable (double acid) P or K were not found in the soil.
Rate of Dry Matter Accumulation in Soybean Seeds with Varying Source‐Sink Ratios1
Authors: Egli D. B. , Leggett J. E. 
Published: July 2010

AbstractThe rate of accumulation of dry weight in the seed is one important process in yield production by grain crops. Information on factors influencing the seed growth rate are needed to help identify yield limiting processes. This study was undertaken to determine the effect of varying source‐sink ratios on the rate of dry matter accumulation in seed of soybeans (Glycine max (L.) Merr.). The varying source‐sink ratios were obtained by removing approximately 50% of the pods or 66% of the leaf area (two leaflets from each trifoliolate leaf) at the end of the flowering period. The study was conducted for 2 years in the field.The pod removal treatment reduced pod number by 20% at maturity and resulted in an increase in weight/seed over the control near the end of the filling period in one of the years. Removal of two‐thirds of the leaf area reduced the weight per seed near the end of the filling period in both years of study. Pod weights of the pod removal treatments were generally heavier than the control and the pods from the leaf removal treatments were lighter than the control. Defoliation lowered the concentration of sugar in the stem sap compared with the control; but, pod removal increased the concentration of stem sugars only near the end of the filling period. The data are interpreted as suggesting that seed growth rates are not closely related to photosynthate production and that storage carbohydrates serve as a buffer between seed growth and photosynthate production.
A System and Program for Monitoring CO2 Concentration, Gradient, and Flux in an Agricultural Region1
Authors: Rosenberg Norman J. , Verma Shashi B. 
Published: July 2010

AbstractBecause of the changing global concentration of carbon dioxide and the possible effects of this change on photosynthetic activity worldwide, a program has been developed for monitoring atmospheric carbon dioxide concentration and gradients representative of a large agricultural region. The program is carried out at Mead, Neb. A meteorological tower is equipped with sampling intakes at various elevations up to 16 m, through which air is drawn to the laboratory for analysis with infra‐red gas analyzers. An automatic calibration system has been developed to permit hourly checks of analyzer performance. Profiles of wind speed and air temperature are also measured. The equipment, the calibration techniques, and the errors associated with the measurements of CO2 concentration and gradients are described. Some initial observations of CO2 concentrations and fluxes are presented.
Differential Response of Soybean Cultivars to Metribuzin1
Authors: Wax L. M. , Stoller E. W. , Bernard R. L. 
Published: July 2010

AbstractMetribuzin [4‐amino‐6‐tert‐butyl‐3‐(methylthio)‐as‐triazin‐5(4H)one] controls several species of troublesome annual broadleaf weeds in soybeans [Glycine max (L.) Merr.] but it sometimes causes excessive crop injury. To determine the extent to which this injury is caused by differential sensitivity of cultivars to metribuzin, we evaluated the response of approximately 250 soybean cultivars to soil‐incorporated metribuzin in field experiments in 1973 and 1974. Most cultivars were relatively tolerant of metribuzin at 0.56 kg/ha. At 0.84 and 1.7 kg/ha, many entries were severely injured or killed. Some of the most sensitive cultivars were ‘Altona,’ ‘Hurrelbrink,’ ‘Norman,’ ‘Portage,’ ‘Semmes,’ ‘Tracy,’ and ‘Vansoy.’ These cultivars, and possibly others with only moderate resistance to metribuzin, should probably be avoided when metribuzin is to be used for weed control.
Effects of Concentrated Superphosphate and Potassium Chloride on Residual Available P, K, and Cl in Three Depths of Soil Derived From Calcareous Glacial Till1
Authors: Peck N. H. , MacDonald G. E. , Vittum M. T. , Lathwell D. J. 
Published: July 2010

AbstractThere is increasing concern by the general public about possible pollution of the environment resulting from applications of commercial fertilizers. This concern may conflict with the need to apply adequate, but not excessive, fertilizers to obtain optimum and economical production of crops. Thus a long‐term field experiment was designed to determine cumulative effects of applications of 0, 84, 336, and 1,344 kg concentrated superphosphate (CSP) and 0, 67, 268, and 1,072 kg potassium chloride (KCl)/ha on the uptake of P, K, and Cl by plants and on residual available soil P, K, and Cl. Applications of CSP and KCl were made nine times in 10 years to a Honeoye fine sandy loam (Glossoboric Hapludalf, fine loamy, mixed, mesic). Without fertilizer CSP and KCl, more P and K was taken up by vegetables and alfalfa than was measured as available by Morgan's extraction solution in the top 0 to 25 cm of soil. Applications of 84 kg CSP (17.5 kg P) and 268 KCl (140 kg K) per ha nearly equalled the average annual uptake of P and K by the plants over the 10‐year period. Residual available soil P accumulated in the top 0 to 25 cm of soil with the two highest rates of CSP, and available soil K accumulated with the highest rate of KCl. Downward movement of P, K, and Cl into the 24 to 43 cm and 43 to 61 cm depths of soil was measured by Morgan's and 1:1 (soil:water) extractions. In conclusion, P accumulated in the surface soil to a greater extent than K and Cl from fertilizers, while K and especially Cl moved downward in the soil more than P.