Seasonal changes in the nitrogen content of three warm-climate pasture grasses

1964 ◽  
Vol 4 (15) ◽  
pp. 336 ◽  
Author(s):  
EF Henzell ◽  
DJ Oxenham
Keyword(s):  
Nitrogen Content ◽  
Nitrogen Fertilizer ◽  
Nitrogen Deficiency ◽  
Nitrogen Supply ◽  
High Rate ◽  
Warm Climate ◽  
Stage Of Development ◽  
Pasture Grasses ◽  
Chloris Gayana ◽  
Nitrogen Treatments

The nitrogen content of three pasture grasses was measured under irrigation at Samford, south-east Queensland, during the period February-September 1962. The grasses were Paspalum plicatulum, Sefaria sphacelata, and Chloris gayana. Two nitrogen treatments were used-nil, and a high rate. The high rate comprised frequent nitrogen fertilizer dressings in amounts chosen to match the shape of the plant growth curve. Addition of nitrogen fertilizer caused a marked increase in the nitrogen content of all parts of the plant and maintained a higher nitrogen content in mature grass samples. Flowering had relatively less effect on the nitrogen content of the grasses than nitrogen supply. Frost had very little effect on the nitrogen content of these grasses. It is suggested that warm-climate pasture grasses generally are subjected to a greater degree of nitrogen deficiency than their temperate counterparts, and that this accounts, at least in part, for their comparatively low nitrogen content. In the nil nitrogen treatment, Setaria sphacelata and Chloris gayana consistently exhibited a higher nitrogen content than Paspalum plicatulum. The differences were greatest in the leaf blades and least in the stems. The relative influences of nitrogen supply and stage of development on the nitrogen content of pasture grasses are discussed.

Influence of Light Regime and Leaf Nitrogen Concentration on 77k Fluorescence in Leaves of Four Tropical Grasses: No Evidence for Photoinhibition

1988 ◽  
Vol 15 (5) ◽  
pp. 669 ◽  
Author(s):  
MM Ludlow ◽  
SP Samarakoon ◽  
JR Wilson
Keyword(s):  
Nitrogen Content ◽  
Nitrogen Availability ◽  
Nitrogen Concentration ◽  
Chlorophyll Concentration ◽  
Leaf Nitrogen ◽  
Nitrogen Supply ◽  
Poor Growth ◽  
Full Sunlight ◽  
Nitrogen Treatments ◽  
Low Nitrogen

This work was undertaken to determine if the stimulation of growth associated with shading of some tropical C4 grasses growing on soils with low to moderate nitrogen availability is partly due to overcoming photoinhibition (i. e. damage caused by excessive light). Four grasses (green panic, carpet grass, buffalo grass and kikuyu) were grown in full sunlight and at 37% of full sunlight, and given a low or high nitrogen supply. Despite differences of up to twofold in leaf nitrogen and chlorophyll concentration between high and low nitrogen treatments in all four grasses, photoinhibition measured by reduction in chlorophyll fluorescence was less than 3% in leaves of low nitrogen content that developed in full sunlight. Therefore, photoinhibition is not a contributor to the poor growth of nitrogen-limited grasses in full sunlight. A second objective was to determine if low nitrogen content predisposed shade-grown leaves to photoinhibition when they were subsequently exposed to full sunlight. Green panic plants that had been given either high or low nitrogen supply and grown in 37% of full sunlight were transferred to full sunlight and the extent of photoinhibition was followed over 8 days. The amount of photoinhibition that occurred was small (<6%) compared with plants grown at either nitrogen level in full sunlight. Therefore, shade and low nitrogen content separately or in combination did not cause any appreciable photoinhibition in green panic.

The nitrogen nutrition of the peach tree. IV. Storage and mobilization of nitrogen in mature trees

1969 ◽  
Vol 20 (5) ◽  
pp. 869 ◽  
Author(s):  
BK Taylor ◽  
den Ende B van
Keyword(s):  
Nitrogen Content ◽  
Total Nitrogen ◽  
Fruit Set ◽  
Growing Season ◽  
Nitrogen Supply ◽  
Soluble Nitrogen ◽  
Nitrogen Status ◽  
Mature Trees ◽  
Nitrogen Treatments ◽  
Peach Trees

An experiment was carried out on 8-year-old peach trees in the field to further study the chemical composition of storage nitrogen in mature trees and to relate tree performance in one growing season to the level of storage nitrogen in tree tissues during the previous winter. Storage nitrogen in dormant trees consisted mainly of soluble organic nitrogen, and free arginine was a principal constituent of this fraction. The arginine nitrogen content of the soluble nitrogen fraction increased with increasing nitrogen supply, but values were low compared with those found in young peach trees. The concentration of arginine in roots of dormant trees was the most sensitive indicator of the nitrogen status of the trees. In comparison, conventional leaf analysis for total nitrogen in midsummer was only about one-half as sensitive as an index of nitrogen status. Since there could be objections to using root tissue for analysis it is of interest to note that the next best estimate of the nitrogen status of the trees was given by the level of arginine nitrogen in leaf + flower buds. The growth of new shoots and especially the nitrogen content of leaves were in proportion to the levcl of storage nitrogen in dormant trees before growth commenced. However, flowering performance and fruit set per tree were not dependent upon the level of storage nitrogen in the trees. Flowers at full bloom from nil nitrogen and plus nitrogen treatments contained approximately the same content of total nitrogen and this may be the reason why nitrogen treatments did not influence fruit set. Nitrogen analyses and field observations indicated that stored nitrogen in nil nitrogen trees was preferentially used for reproductive processes rather than for vegetative growth. The amount of total nitrogen per leaf first increased and then decreased with elapsed time during the growing season. This latter loss was attributed to migration of nitrogen from ageing leaves to fruits and/or woody tissues in late summer and early autumn. Nitrogen treatment did not significantly alter the proportion of total nitrogen lost per leaf at this time, but the amount of total nitrogen lost per leaf usually increased with increasing nitrogen supply. Results are compared with those obtained in earlier work and the importance of reaccumulation of nitrogen from abscising leaves in the nitrogen economy of the trees is briefly discussed.

A view at the Russian economic transformation

2018 ◽  
pp. 142-158 ◽  
Author(s):  
E. F. Baranov ◽  
V. A. Bessonov
Keyword(s):  
Market Economy ◽  
Growth Rates ◽  
Transition Process ◽  
Well Being ◽  
Economic Transformation ◽  
High Rate ◽  
Russian Economy ◽  
Stage Of Development ◽  
Qualitative Level ◽  
Rate Of Recovery

The transition of the Russian economy from plan to market is considered at a qualitative level. The analysis of economic dynamics in the transformation paradigm is conducted. The main stages of the transition process are discussed. Bonuses and costs due to the transition to market economy are considered. The reasons for the outstripping growth of well-being as compared to the growth of output are discussed. The signs of exhaustion of the potential of factors ensuring an abnormally high rate of recovery and accompanying welfare growth are discussed. The conclusion is made that the transformational recovery has been completed. The Russian economy has moved to the stage of development with relatively low growth rates of output and welfare, typical for stable (nontransition) economies.

Rhizobium Inoculation Increases of Bean and Maize Yields in Intercrops on Farms in the Peruvian Sierra

1994 ◽  
Vol 30 (3) ◽  
pp. 311-318 ◽  
Author(s):  
P. Pineda ◽  
J. A. Kipe-Nolt ◽  
E. Rojas
Keyword(s):  
Plant Growth ◽  
Nitrogen Fertilizer ◽  
Growth Response ◽  
Nitrogen Deficiency ◽  
Selection Strategy ◽  
Small Scale ◽  
Rhizobium Inoculation ◽  
Plant Growth Response ◽  
Maize Yields ◽  
Small Scale Farmers

SUMMARYNitrogen deficiency severely limits production of the bean–maize association grown by small-scale farmers in upland Peru. Sixty-four bean Rhizobium isolates were evaluated for induction of a plant growth response in pots of soil from the area and 14 of the most promising strains of these were tested on farmers' fields in 13 trials over a three year period. Bean yields were increased by inoculation with at least one Rhizobium strain in seven of the trials, with increases ranging from 0.21 to 0.68 t ha−1. Bean yields were not increased by the application of 120 kg N ha−1 to the intercrop. Maize yields were increased by Rhizobium inoculation in nine of the 13 trials by between 0.34 and 1.85 t ha−1. Maize responded to nitrogen fertilizer on the same nine farms. This Rhizobium selection strategy, although laborious, was effective in identifying strains that can be recommended for use as inoculants by farmers in the region.

Interleukin-5 (IL-5) and IL-6 define two molecularly distinct pathways of B-cell differentiation

1993 ◽  
Vol 13 (7) ◽  
pp. 3929-3936
Author(s):  
T D Randall ◽  
F E Lund ◽  
J W Brewer ◽  
C Aldridge ◽  
R Wall ◽  
...  
Keyword(s):  
Cell Differentiation ◽  
B Cells ◽  
B Cell ◽  
B Cell Lymphoma ◽  
Receptor Expression ◽  
High Rate ◽  
B Cell Differentiation ◽  
Interleukin 5 ◽  
Stage Of Development ◽  
Differentiation Factors

Interleukin-5 (IL-5) and IL-6 have both been reported to act as B-cell differentiation factors by stimulating activated B cells to secrete antibody. However, it has not been possible to directly compare the effects of these two lymphokines because of the lack of a suitable B-cell line capable of responding to both. We have identified a clonal, inducible B-cell lymphoma, CH12, that has this property. Both IL-5 and IL-6 can independently stimulate increases in steady-state levels of immunoglobulin and J-chain mRNA and proteins, and they both induce the differentiation of CH12 into high-rate antibody-secreting cells. Nevertheless, there are significant differences in the activities of these two lymphokines. First, while IL-6 acts only as a differentiation factor, IL-5 also augments the proliferation of CH12 cells. Second, the differentiation stimulated by IL-5 but not by IL-6 is partially inhibited by IL-4. Inhibition of IL-5-induced differentiation was not at the level of IL-5 receptor expression, since IL-4 did not inhibit IL-5-induced proliferation. Third, IL-5 but not IL-6 stimulated increased mouse mammary tumor proviral gene expression in CH12 cells. These results demonstrate that while both IL-5 and IL-6 may act as differentiation factors for B cells, they induce differentiation by using at least partially distinct molecular pathways. Our results also establish that B cells characteristic of a single stage of development can independently respond to IL-4, IL-5, and IL-6.

EFFECT OF SULPHUR TREATMENTS ON YIELD AND NITROGEN AND SULPHUR CONTENT OF ALFALFA GROWN ON SULPHUR-DEFICIENT AND SULPHUR-SUFFICIENT GREY WOODED SOILS

1961 ◽  
Vol 41 (4) ◽  
pp. 709-715 ◽  
Author(s):  
R. R. Cairns ◽  
R. B. Carson
Keyword(s):  
Nitrogen Content ◽  
Relative Abundance ◽  
Nitrogen Assimilation ◽  
Calcium Sulphate ◽  
Nitrogen Supply ◽  
Physiological Functions ◽  
Root Nodulation ◽  
Main Effect ◽  
Sulphate Sulphur ◽  
Elemental Form

Sulphur applied in the elemental form, or as sodium or calcium sulphate, on Grey Wooded soils, increased yields of alfalfa on sulphur-deficient Loon River loam, but not on sulphur-sufficient Garrick loam. The quantity of sulphate-sulphur was extremely low in the alfalfa grown on untreated Loon River loam and increased markedly as a result of the application of sulphur to the soil. Although herbage from untreated areas of the sulphur-deficient soil contained a slightly higher per cent nitrogen in 1955 than that grown on the sulphur-sufficient soil, sulphur treatment increased nitrogen content and yield of nitrogen on the sulphur-deficient soil. The relative abundance of nitrogen in the herbage grown on the check areas of the deficient soil suggests that the main effect of sulphur was not on root nodulation or nitrogen supply, but rather on nitrogen assimilation and other physiological functions of the sulphur-containing compounds within the plant.

EFFECT OF NITROGEN AND PHOSPHORUS FERTILIZATION ON WILD OATS AND SPRING WHEAT

1963 ◽  
Vol 43 (1) ◽  
pp. 64-69 ◽  
Author(s):  
J. J. Sexsmith ◽  
G. C. Russell
Keyword(s):  
Seed Yield ◽  
Spring Wheat ◽  
Nitrogen Fertilizer ◽  
High Rate ◽  
Phosphorus Fertilization ◽  
Wild Oat ◽  
Measurable Effect ◽  
Nitrogen And Phosphorus ◽  
Wild Oats ◽  
Loam Soil

Spring wheat, with fertilizer applied in the drill rows, was grown in wild-oat-infested stubble on a Shallow Lethbride loam soil for 4 years, Phosphorus had no measurable effect on the height, straw weight, seed yield, or number of wild-oat plants. In contrast, nitrogen increased the number of seed-bearing stems, plant height, straw weight, and seed yield, but did not change the wild-oat stand. Wheat yields were increased by nitrogen and further increased by the addition of phosphorus at the rate of 20 pounds of P2O5 per acre in 3 of the 4 years. Measured bushel weight of the wheat increased with nitrogen fertilizer additions and was further increased by phosphorus except at the high rate of both materials. Fertilizer applications, under conditions similar to those encountered in this test, may be useful for increasing wheat production, but only at the expense of producing increased quantities of wild-oat seed.

scholarly journals Capitalization as a Tool for Managing the Development of Industry and Rail Transport

2019 ◽  
Vol 67 ◽  
pp. 01010
Author(s):  
Igor Posokhov ◽  
Victoriia Cherepanova ◽  
Olha Podrez
Keyword(s):  
Occupational Injury ◽  
Programming Model ◽  
Rapid Development ◽  
Rail Transport ◽  
High Rate ◽  
Real Economy ◽  
Industrial Enterprises ◽  
Stage Of Development ◽  
Environmental Measures ◽  
High Level

The Ukrainian real economy encounters similar problems that do not allow its rapid development – high level of wear of productive assets, lack of modern equipment, outdated technologies, inappropriate environmental measures, high rate of occupational injury, etc. All this requires designing of new tools to manage the development of such important sectors of economy as industry and rail transport. Therefore, the urgent issues at the current stage of development of these industries include the definition of conditions for fixed assets capitalization and the sources of its financing. The scientific novelty of the results is identification and justification of the capitalization main components, determining the sources of funding and the mechanism for their attraction. The tool for managing the productive and environmental protection assets capitalization has been designed which is optimized using a two-dimensional dynamic programming model. The results obtained are the basis for the practical solution of the problem, and for further scientific research. This approach allows solving the problem of rail transport and industrial enterprises capitalization in a comprehensive manner, which contributes to their sustainable development.

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