Compare Growth Responses Research Articles

Comparative growth responses of perennial forage legumes in hill‐land ultisols and their relationship to soil acidity‐related factors

Abstract As soils of humid, temperate hill‐lands are typically highly weathered, mineral, and acidic, forage legumes for these conditions need to be evaluated, and limiting soil acidity‐related factors determined. Two ultisol topsoils (0–15 cm) from Appalachian hill‐lands of the Lily series (Typic Hapludults) were utilized 1n a growth chamber experiment. Both soils were of similar pH and low 1n fertility but different in % base saturation due to different management histories (abandoned versus poorly‐managed pasture). Treatments to provide a range of soil pH values (aluminum, nil, calcium) were applied to ascertain their effect on various growth response traits of alfalfa (Medicago sativa L.), red clover (Trifolium pratense L.), white clover (Trifolium repens L.), birdsfoot trefoil (Lotus corniculatus L.), big flower vetch (Vicia grandiflora Scop.), and flatpea (Lathyrus sylvestris L.). Averaging over all soils and treatments, shoot production Increased 1n the order‐alfalfa < red clover, white clover, tre...

Postthinning growth and yield of row-thinned and selectively thinned loblolly and slash pine plantations

This study compared growth responses in planted loblolly pine (Pinustaeda L.) and slash pine (P. elliottii Engelm.) stands thinned by using three row-felling methods and at the same density levels, three selective felling methods. The study plots were in six plantations, aged 15–22 years, located in central Louisiana. Growth was measured 5 and 10 years after plot installation. Site index varied from 19.5 to 31.7 m (base age 50) and initial planting densities ranged from 1993 to 2989 trees/ha. Study results show there will likely be less diameter increment and less net basal area and cubic-metre volume per unit area growth and yield, and the growth will be in smaller-sized trees, if row thinning is used rather than selective thinning from below. These differences will probably be greater in slash pine plantations than in loblolly pine plantations.

Comparative growth responses of N2-fixing and N-fertilized subterranean clover on acid soils

Effects of soil chemical properties on biological N2-fixation (BNF) byTrifolium subterraneum L. ‘Mt. Barker’ —Rhizobium trifolii strain 162×95 were studied on thirteen soils in a greenhouse experiment. Dry matter production of inoculated/+N plants indicated three groups of soils. Mean soil solution activities of Al3+ were 29.4, 9.8 and 0.1 μM for groups of soils with no BNF, limited BNF, and unlimited BNF, respectively. Using easily measurable soil chemical properties, the following equation related relative dry matter production to pH and soil Al saturation: Inoculated/+N×100=−140+46.83 (soil solution pH) −0.31 (Al concentration ×100/CEC) (r2=0.66).

Comparative Growth and Biochemical Response of Very Low Birthweight Infants Fed Own Mother's Milk, a Premature Infant Formula, or One of Two Standard Formulas

Summary:Very low birthweight (VLBW) infants weighing &lt; 1,600 g at birth were fed their own mother's milk (OMM) or randomly assigned to receive one of three formulas: a “humanized” formula (SF), a partially modified casein‐predominant cow's milk formula (CF), or a premature formula (PF). All infants were fed at 120 kcal/kg/day where possible, PF infants had significantly greater weight increments (28.0 g/day) than those on OMM (19.4 g/day), SF (18.9 g/day), and CF (18.2 g/day). Those on PF also had greater increments of length, head circumference, and skinfold thickness than those on the other two formulas and greater length increments than those on OMM. Dynamic skinfold measurements suggested that no infants accumulated excessive amounts of interstitial fluid. Infants on the two standard formulas had significantly greater base deficits, whereas those on CF also had higher urea values. Those on OMM had lower phosphate and higher alkaline phosphatase values than the other groups. Thus VLBW infants fed a premature formula had better growth and fewer biochemical problems than those on standard formulas, whereas supplementation of OMM may be necessary to ensure optimal growth and bone mineralization.

The threshold growth response of Lactobacillus casei to 5-methyl-tetrahydrofolic acid: implications for folate assays.

The comparative and absolute growth response of Lactobacillus casei was measured nephelometrically for time periods of 17-23 h in the microbiological assay of folic acid and 5-methyl-tetrahydrofolic acid at concentrations of 0-8 ng/10 ml basal medium at pH 6.8. At concentrations of 0-1 ng/10 ml the comparative growth response to 5-methyl-tetrahydrofolic acid was markedly depressed whereas growth was the same at 2 ng/10 ml and above. Comparative growth was unaffected by the length of assay incubation, depressed growth being due to differences in log-phase growth rates with the rate-plot for 5-methyl-tetrahydrofolic acid being sigmoidal and for folic acid being a rectangular hyperbola with linearity only in the 0-1 ng/10 ml range. The reciprocal rate-plot for folic acid was linear whereas that for 5-methyl-tetrahydrofolic acid was coincidental only in part, giving rise to the same estimate of maximum velocity and substrate concentration for half-maximum velocity, with the exhibition of a strong threshold at low concentration. A previous observation (Phillips & Wright, 1982) that the L. casei growth response to 5-methyl-tetrahydrofolic acid may be significantly less than that to folic acid is confirmed as is the long-established view that the response to both folates may be equal. In the light of current knowledge regarding folate-binding, transport and metabolism by L. casei, it is argued that the intracellular oxidation of 5-methyl-tetrahydrofolic acid to 5, 10-methylene-tetrahydrofolic acid is a rate-limiting step at low substrate concentrations, subsequently giving rise to a threshold growth response peculiar to 5-methyl-tetrahydrofolic acid.(ABSTRACT TRUNCATED AT 250 WORDS)

The Relative Response of Two Foxtail (Setaria) Species to Diclofop

ED50values (the dosage required to reduce the posttreatment gain in dry weight by 50%) for diclofop applied to green and yellow foxtail [Setaria viridis(L.) Beauv. ♯3SETVI andS. lutescens(Weigel.) Hubb. ♯ SETLU] at the two- and four-leaf stages were calculated from linear regression equations derived by plotting the logarithm of the applied dosage against the relative growth reduction expressed as a probit value. At the two-leaf stage, green foxtail was more susceptible to the chemical than yellow foxtail but at the four-leaf stage there was no significant difference in response of the two species. At least part of the difference in sensitivity of the two species at the two-leaf stage could be accounted for by differences in spray retention, with green foxtail retaining 1.8 times (expressed as μL/cm2) or 3.5 times (expressed as μL/g dry weight) as much spray as yellow foxtail, despite the fact that yellow foxtail had a greater projected leaf area. At the four-leaf stage, the amount of spray retained by both species calculated on a per gram dry-weight basis was significantly less than at the two-leaf stage, accounting in part for the higher ED50values obtained at the later growth stage. However, there appeared to be no direct relationship between the amount of spray retained and the comparative growth response of the two weeds at the later stage of application.

Determination of cobalamins in biological material: II. The cobalamins in human plasma and erythrocytes after desalting on nonpolar adsorbent material, and separation by one-dimensional thin-layer chromatography

An improved method for determination of cobalamins in biological materials is described. The cobalamins are extracted with ethanol after preincubation with cadmium acetate, which inhibits nonspecific adsorption of hydroxocobalamin to proteins. The extracts are desalted on Amberlite XAD-2 columns, which at least doubles the capacity of the analysis, as compared to the previous phenol procedure. The cobalamins are separated by one-dimensional thin-layer chromatography. Bioautography with Escherichia coli strain 113-3 is performed after the light-sensitive cobalamins and hydroxocobalamin have been converted to sulfitocobalamin. This is done in order to ensure comparable growth responses to equal amounts of the cobalamins. Reference intervals of plasma and erythrocytes of healthy blood donors for methyl-, 5'-deoxyadenosyl-, cyano-, hydroxo/aquo-, and sulfitocobalamin are presented. The differences between the present and previous results are discussed.

Comparative Growth and Atrazine Response of Resistant and Susceptible Populations of Amaranthus From Southern Ontario

(1) Growth characteristics and response to atrazine were studied in atrazine resistant (R) and susceptible (S) populations of Amaranthus retroflexus and A. powellii from several localities in southern Ontario. (2) Six weeks after sowing, in the absence of atrazine, plants of A. powellii were taller and had more leaves and heavier stems, while plants of A. retroflexus had greater leaf weights. R plants of A. powellii were taller and had heavier stems than S plants. R and S plants of A. retroflexus did not differ significantly in growth characteristics. (3) Differences in response to atrazine between R and S populations were essentially the same for A. powelli and A. retroflexus. S plants showed extensive leaf chlorosis and a marked decrease in leaf and stem weight after treatment with atrazine. R plants, especially of A. powellii, showed increased leaf weights and leaf numbers, suggesting a stimulatory effect of the herbicide. R populations were generally less variable with respect to growth characteristics than S populations. The within-population variability of R and S populations tended to increase with increasing levels of atrazine. (4) At maturity, in the absence of atrazine, A. retroflexus and A. powellfi differed in height and biomass production but not in the number of days to flowering or in reproductive effort. R and S plants did not differ significantly in the amount of seed produced per plant in non-competitive conditions. Plants from more southerly populations in southern Ontario were taller and produced more biomass at maturity than plants from more northerly populations.

Growth of Subterranean Clover in a Range Soil as Affected by Microclimate and Phosphorus Availability. III. Comparative Growth of Subterranean and Rose Clovers at Cold Soil Temperatures1

AbstractThe biological yield potential of winter annual range legumes is influenced by the timing of rainfall adequate to ensure germination. If rains are late, the establishment phase of growth must occur at cold soil and air temperatures. On low‐P soils, this combination of abiotic factor constraints can limit symbiotic N fixation.We conducted three controlled‐environment experiments to compare the seedling growth of rose clover (Trifolium hirtum All., ‘Hykon’) and subterranean clover (T subterrateum L., ‘Mt. Barker’, hereafter referred to as subclover) on a P‐deficient soil (Sobrante‐Las Posas association), simulating winter conditions of cold soils and low light. Comparative growth responses, especially intraplant dry matter partitioning and nodulation, were observed for several soil P availability levels.A sunlit phytotron provided a common shoot environment of seasonal (fall/winter) ambient light intensity and photoperiod, with a programmed smooth diurnal temperature cycle of 20 C maximum and 5 C minimum. Three independently‐controlled water baths maintained soil temperature experiments at a constant 5 C, a constant 10 C, and a diurnal 5 C to 10 C alternation. Phosphorus levels were 0, 45, 90, and 180 kg/ha equivalents. Growth intervals (5 ± 0.5 trifoliolate‐leaf stage), varied between 58 and 114 days.Leaf area of subclover was greater than that of rose clover, and responded more to increasing P levels. Leaf areas tended to increase with higher soil temperatures. Nodule weight was positively correlated with leaf area; nodule weight:leaf area regressions suggested that nodule development was adequate at 5 C and that nodule development was primarily related to time rather than to morphological development of the shoot. Nodule weights were similar for the two species, and low at 0 P.The results suggest that while the practical soil threshold temperature for overall growth is near 5 C, some intraplant growth processes may proceed, but only at adequate, availability levels of mineral nutrients. These relationships may be particularly important where range annual legumes are being introduced as part of a more general range improvement program.

Compensatory Growth of Tall Fescue Following Drought1

AbstractEnhancement of growth following short periods of drought stress has been reported in several crop species. If such enhancement follows summer drought‐stress of cool‐season forage grasses, the increased yield from summer irrigation may be offset partially by compensatory growth during fall. Therefore, a 3 year field study was conducted to compare growth responses of tall fescue (Festuca arundinacea Schreb.) grown with and without supplemental irrigation from June through August. Soil was Mexico silt loam (Udollic Ochraqualf) and fertilizer was applied in spring and following each cutting. Plots were harvested six times in 1971, five times in 1972, and four times in 1973. A residual harvest was made on 21 May 1974.During summer the plants that were irrigated had greater forage yields, greater tiller density, greater weight per tiller, higher leaf elongation rates, and higher concentration of water‐soluble carbohydrates (WSC) in leaf tissue as compared with plants that were water‐stressed. Concentration of WSC in stem bases during summer was higher in the water‐stressed plants. Fall growth of plants that had been water‐stressed during summer was greater than that of those that had been irrigated. The enhancement of growth or compensatory effect was associated with higher concentration of WSC in stem bases during late summer, and faster leaf elongation and greater weight per tiller during fall of the previously water‐stressed plants as compared with the summer‐irrigated plants.Compensatory growth following drought stress was still evident the following spring, as indicated by the higher tiller density and greater forage yield. However, the collective compensatory yield of the water‐stressed plants during fall and spring was not great enough to compensate for lower yields during summer. In the third year of the study normal rainfall during summer was higher than duing the first 2 years, and no compensatory growth was noted during fall or the following spring.During the 3‐year study, total yield for the irrigated treatments was 4% larger than that for the water‐stressed treatment. The major response to irrigation was a shift in season of production. Management and breeding objectives should consider the effect of summer irrigation or summer drought on the subsequent performance of cool‐season forage grasses.

Comparative gas exchange and growth responses of C3 and C4 beach species grown at different salinities.

Comparative laboratory gas exchange and relative growth rate experiments were conducted on three native California coastal strand species at four salinity treatment levels. Relative mesophyll conductance sensitivities to salinity of Atriplex leucophylla (Moq.) D. Dietr. (C4) and Atriplex californica Moq. in D.C. (C3) were nearly identical. Mesophyll conductances of both species were stimulated by moderate levels of salinity. Mesophyll conductances of Abronia maritima Nutt. ex Wats. (C3) were highest in the absence of salinity and depressed by increasing levels of salinity. Increasing levels of salinity generally decreased net photosynthesis and leaf conductances but increased water use efficiencies. The C4 species, Atriplex leucophylla, had higher mesophyll conductances and water use efficiencies at all salinity levels than the C3 species. The effects of salinity on relative growth and net assimilation rates of greenhouse grown plants were not directly correlated with the effects on net photosynthesis measured in the laboratory. Growth of Abronia maritima was greatly stimulated by low levels of salinity whereas photosynthesis was substantially inhibited. The possible significance of C4 photosynthesis in relation to salinity is discussed.

Availability of tryptophan in some feedstuffs for swine.

SUMMARY Two experiments were conducted to determine the availability of tryptophan (Try) from corn (NC), opaque-2 corn (OC), milo (M) and freeze dried alfalfa (FDA) when fed to swine. The first experiment consisted of a growth trial involving 96 baby pigs and eight treatments. The basal diet containing .06% Try and 24.5% protein was supplemented with .015%, .030% and .045% L-Try. These four diets were used to establish a standard curve for growth. The other treatments were formed by adding the feedstuffs as the source of Try to the basal diet. Availabilities were determined by comparing growth responses. Try availabilities from NC, OC, M and FDA were 70, 58.3, 70 and 83.3%, respectively, when gain was used as the response criterion, and 77, 65, 85 and 80% when gain/feed was the response criterion. Plasma Try, muscle RNA and DNA and muscle polysome profiles were used as criteria for assessing the availability of Try. Dietary levels of Try showed a quadratic effect (P<.01) on plasma Try and no apparent effect on the muscle parameters. In the second experiment, post-prandial changes in blood Try levels were used as a measure of Try availability from FDA. Analysis of blood from pigs fed the dietary treatments (growth curve) used in experiment 1 plus the treatment with FDA as the source of Try showed an increase in Try level that peaked irregularly between 15 and 45 min post-feeding followed by a marked decrease that plateaued

Effect of Herring Oil on Body Weight, Comb Size and Gonadal Development in the Chick

A diet with 20% herring oil (0.55% linoleate) gave comparable growth responses to a diet containing 20% corn oil (12.07% linoleate) in 4-week-old male and female White Leghorn chicks. No additive or synergistic growth responses were noted in female chicks fed a mixture of herring oil and corn oil. Decreased testes size and changes in testicular histology occurred in young cockerels fed herring oil. Comb responses were dissimilar in male and female chicks fed fish oil.

Fat Supplemented Grain Rations for Veal Production

Two studies were used to compare growth responses and carcass qualities of 36 Holstein bull calves fed a) whole milk; b) calf starters with 5% animal fat; c) calf starters without supplemental fat; and d) digestible energy (DE) to digestible protein (DP) ratios of 22.9, 24.4, 24.6, 26.1, 28.3, 34.6, and 40.4kcal DE per gram DP in the calf starters. All calves fed the calf starter rations were offered 3.9kg of whole milk daily until weaning at 6 weeks of age. Calves continued on the whole milk diet in Study I were offered milk at 10% of body weight to begin and gradually increased to a maximum of 15%. In Study II milk intake was gradually increased to satiety in 3 feedings daily. Average initial weights of starter-fed calves were 57.6kg (Study I) and 72kg (Study II). Milk fed calves weighed 41.9 (Study I), and 52kg (Study II), initially. Weights at slaughter of starter-fed calves were 110 (Study I) and 125kg (Study II). Milk-fed calves weighed 104 (Study I) and 125kg (Study II). Average daily gains (kg) and feed efficiency (kg dry matter per kg gain) of milk-fed calves were: .77, 1.24 (Study I) and 1.11, 1.38 (Study II). Comparative responses from calf starters containing 5% fat and different DE:DP ratios were: 1.04, 2.27 (ratio 34.6:l); .87, 2.60 (ratio 40.4:l) in Study I, and 1.14, 2.47 (ratio 26.1:l); 1.12, 2.39 (ratio 24.6:l) in Study II. Without added fat observed values included: 1.09, 2.43 (ratio 28.3:l) in Study I, and 1.26, 2.58 (ratio 24.4: 1) ; 1.24, 2.48 (ratio 22.9:l) in Study II. The DE:DP ratio of 34.6:l was optimal for protein and energy utilization and animal growth response. A ratio of 40.4:l was too wide (P<.05). Dressing percentages (hides removed) were 60.8% (milk-fed) and 53.84% (P<.01) (grain-fed). Hemoglobin values were 8.5 (milk-fed) and 12.6 g/100ml blood (P<.01) (grain-fed). The meat of starter-fed was slightly darker red. Supplemental animal fat in starters increased (P< .05) kidney fat, external fat cover, and resulted in carcass fat characteristics comparable to milk-fed calves. Chemical composition of meat taken from the 10th, 11th, and 12th rib section was not altered (P<.05) by rations. Cooking properties, taste panel test comparisons, and tenderness were unaffected (P> .05) by treatments. Acceptable veal can be produced with high energy grain rations.

Effects of Ammonium Polyphosphates on Yield1 and Chemical Composition of Irrigated Corn

AbstractIrrigated corn (Zea mays L.) grown on Zn‐deficient, slightly acid Cass fine sandy loam suffered from increasingly severe Zn deficiency when 40 kg/ha P (80 lb/A P2O5) was applied in a band to the side and below the seed. Zinc deficiency was corrected in the presence of the banded P when Zn was supplied at the rate of 11.2 kg Zn/ha as ZnSO4.Banded applications of ammonium polyphosphate (APP) in the presence of inadequate Zn tended to induce more severe Zn deficiencies than did similar applications of monoammonium phosphate (MAP). When adequate Zn was supplied, the two forms of P produced comparable plant growth responses and grain yields. Yield depressions noted with the use of banded APP without adequate Zn were associated with higher plant P contents than when the plants were supplied with MAP. High levels of plant P were concomitant with low levels of Zn in the plants. Banded applications of P resulted in higher plant concentrations of P than did broadcast P applications and induced more severe Zn deficiencies.When Zn was limiting, grain yields tended to decrease with increasing P concentrations in young plant tissues. In the presence of adequate Zn concentration of P in young plant tissues was positively correlated with grain yields.

Response of Thyroid Hormone-deficient Rats to a Growth Factor in Duodenal Tissue

A procedure for preparing a water-soluble fraction of duodenal tissue is described. This fraction was administered in the drinking water to growth-arrested thyroidectomized and hypophysectomized rats, and its effect was compared with 3,5,3′-triiodo-L-thyronine. Both substances evoked comparable growth responses in these rats, but exerted different effects on certain body tissues. In addition, the duodenal fraction did not prevent goiter in the usual goiter prevention assay. When administered intraperitoneally to thyroidectomized, hypophysectomized or thiouracilfed rats, it had no effect on growth, but it reinstated growth of sulfaguanidine-fed rats whether it was administered orally or parenterally. When the duodenal fraction was digested with pancreatin and then administered to growth-arrested thiouracil-fed rats, a growth response was observed. The data from these experiments suggest that an unknown substance is present in duodenal tissue which is capable of eliciting a growth response in thyroid hormone-deficient rats.

The Effects of Vitamin B12 and Aureomycin on Reproductive Performance in Turkeys

LITTLE information is available concerning the need for vitamin B12 for hatchability of turkey eggs. Based on studies conducted for three hatching seasons, Kratzer (1952) has reported that turkey hens on an animal protein deficient ration performed as well with regard to hatchability of fertile eggs as hens on a practical ration. However, poults from such depleted hens responded to feeding or injection of crystalline vitamin B12 while poults from hens fed normal rations gave no response. Antibiotics elicited comparable growth responses, regardless of the source of the poults. There is also little information available concerning the possible value of antibiotics in the turkey breeder diet. Work at this station (Carlson, Kohlmeyer and Moxon, 1951; and Carlson, unpublished results, 1951) has indicated that supplements containing vitamin B12 and aureomycin, when added to diets deficient in animal protein, have improved hatchability of fertile eggs and/or early growth of poults, particularly during …

Comparative Growth Response of Chicks to Detergents, Germicides and Penicillin ,

IT HAS been reported by Harris, Sherman and Jetter (1951) that synthetic surfactants based on sorbitan and polyoxyethylene polymers were toxic to rats when fed at high levels. Ely (1951) found that a lauryl ethylene oxide condensate and other synthetic detergents, such as are commonly used in household preparations, stimulate early growth of chicks when fed at 0.1% in the diet. In the data presented here, the growth responses of chicks to several detergents and germicides, at various levels in the diet, and to penicillin are compared.PROCEDUREIn the first feeding trial, Single Comb White Leghorn chicks were used. At day of age, they were distributed at random into electrically heated battery brooders so that 43 groups of 15 chicks each were formed. The basal diet shown in Table 1 was used in this and subsequent feeding trials. Supplements were added to this basal diet as indicated in Table 2. .

Study of Selective Media for Coli-Aerogenes Isolation

sacrificing sensitivity to any strains of the coli-aerogenes group. This study has been divided into three parts. The first step was to study the comparative coli-aerogenes productivity or growth response with a variety of strains. The second was to check the inhibitive qualities of these media on some of the common organisms encountered in water analysis which give false presumptive tests in lactose broth. If any of the media prove advantageous during the first steps of this study practical tests will be carried out. At the present time the first section of the study is practically complete and the second part is well under way. All of the work was performed in a number of cooperating laboratories for the committee. The cooperatore on the study include the following: Leo F. Ey and Rosemary Bole, Ohio Department of Health; Michael A. Farrell, Pennsylvania State College; F. W. Gilcreas, New York State, Department of Health; R. F. Goudey and Madeline Lynch, Department of Water and Power, Los Angeles; Murray P. Horwood and C. G. Dunn, Massachusetts Institute of Technology; Bernard H. Jeup and Marion S. Campbell, Indiana Division of Public Health; Stewart A. Koser and Raymond Spoelstra, University of Chicago; A. L. MacNabb and A. D. McClure, Ontario Department of Health; Jane H. Rider, Arizona State Laboratory; Cassandra Ritter, Kansas Board of Health; Col. J. T. Siler and Major H. R. Livesay, Army Medical School; Robert Spaulding Spray, West Virginia University;