Effects of variation in density and phosphate application on growth and composition of Townsville stylo (Stylosanthes humilis)

1970 ◽  
Vol 10 (45) ◽  
pp. 442 ◽  
Author(s):  
KG Rickert ◽  
LR Humphreys
Keyword(s):  
Nitrogen Concentration ◽  
Phosphorus Concentration ◽  
Dihydrogen Phosphate ◽  
Positive Density ◽  
Nitrogen And Phosphorus ◽  
Area Index ◽  
Stylosanthes Humilis ◽  
Plant Densities ◽  
Townsville Stylo ◽  
Phosphorus Application

Townsville stylo (Stylosanthes humilis) was grown at Brisbane from February to June 1967 at initial densities of 10, 50, 250, 1250, and 6250 plants per m2 in boxes of sand which received basal nutrients and applications of 0, 10, and 50 kg P per hectare as calcium dihydrogen phosphate. Plots were irrigated frequently. Wide differences in dry matter yield between plant densities and a positive density phosphorus yield interaction persisted throughout the experiment. Peak yield was 1050 g per m2 with leaf area index (LAI) of 6.8. Intraspecific plant competition was evident in high densities 35 days after emergence, extending to the lower densities by 58 days. Plant mortality at the highest density was independent of phosphorus treatment. Maximum growth rates were reached earlier at high than at low plant densities ; the subsequent decreases in growth rate were expressed through drifts in both LA1 and NAR and were associated with progressively more unfavourable environmental conditions for growth. Nitrogen and phosphorus concentration of both shoots and roots decreased with increasing density. Phosphorus application did not affect nitrogen concentration. Exploitation of native soil phosphorus and recovery of applied phosphorus was greatest in high density swards. The data illustrate the loss in potential production which may occur in sparse swards of Townsville stylo and the limitations to efficient phosphorus response inherent in low density swards.

Performance of Townsville stylo (Stylosanthes humilis) lines in pure swards and with the annual grass (Digitaria ciliaris) under various defoliation treatments at Katherine, N.T

1974 ◽  
Vol 14 (69) ◽  
pp. 495 ◽  
Author(s):  
JR Ive ◽  
MJ Fisher
Keyword(s):  
Dry Matter ◽  
Certified Seed ◽  
Phosphorus Concentration ◽  
Annual Grass ◽  
Nitrogen And Phosphorus ◽  
Matter Production ◽  
Stylosanthes Humilis ◽  
Townsville Stylo ◽  
Better Than ◽  
Late Sowing

Townsville stylo (Stylosanthes humilis) selections collected from twelve naturalized populations, in Queensland and the Northern Territory, and certified seed of the Katherine ecotype ('lines'), were grown for three years in a field experiment at Katherine, N.T. (latitude 14.3�S). In the third year, the experiment was oversown with Digitaria ciliaris. Flowering of all lines was delayed by late sowing, but was hastened by drought. However, the order in which the lines flowered was basically the same for all three years, and similar to that at Lansdown, Queensland (latitude 19.7�S). Although seasonally dependent, highest dry matter production was associated with erect mid- or late mid-season maturity lines which were often lowest in nitrogen and phosphorus concentration. There were no differences between lines in their ability to compete with Digitaria. Grazing reduced the proportion of grass in the swards compared with the forage harvested and non-defoliated treatments largely because Townsville stylo appeared to withstand grazing and trampling better than Digitaria.

The influence of water stress on nitrogen and phosphorus uptake and concentrations in Townsville stylo (Stylosanthes humilis)

1980 ◽  
Vol 20 (103) ◽  
pp. 175 ◽  
Author(s):  
MJ Fisher
Keyword(s):  
Water Stress ◽  
Phosphorus Uptake ◽  
Phosphorus Concentration ◽  
Nitrogen And Phosphorus ◽  
Growth Stresses ◽  
Stylosanthes Humilis ◽  
Influence Of Water ◽  
Nitrogen Concentrations ◽  
Townsville Stylo ◽  
Nitrogen And Phosphorus Uptake

The phosphorus concentrations of Townsville stylo (TS) grown in the Northern Territory are lower than in Queensland, and fall below the requirements of grazing cattle for much of the year. An explanation was sought by measuring N and P in swards subjected to water stress at various times during growth. Stresses during early vegetative (EV), late vegetative (LV) and flowering (F) stages were compared with a well watered control. While nitrogen concentrations were affected little, water stress greatly reduced phosphorus concentrations, the relative effects being EV > LV > F. The EV stress depressed phosphorus concentration to 0.08% compared with 0.20% in the control. Phosphorus level recovered on the relief of stress to the same level as the control. Phosphorus concentration in stems was more sensitive to stress than that in leaves. These results show that if chemical analysis of plants is to be used to indicate the phosphorus status of the soil, the analyses will be unreliable unless the plants have grown without water stress for at least six weeks.

scholarly journals Reducing Nitrogen and Phosphorus Losses from Different Crop Types in the Water Source Area of the Danjiang River, China

2019 ◽  
Vol 16 (18) ◽  
pp. 3442 ◽  
Author(s):  
Mengjing Guo ◽  
Tiegang Zhang ◽  
Jing Li ◽  
Zhanbin Li ◽  
Guoce Xu ◽  
...  
Keyword(s):  
Total Nitrogen ◽  
Total Phosphorus ◽  
Unit Area ◽  
Nitrogen Concentration ◽  
Source Area ◽  
Water Source ◽  
Nutrient Loss ◽  
Phosphorus Concentration ◽  
Nitrogen And Phosphorus ◽  
Bare Land

Nitrogen and phosphorus are essential for plant growth and are the primary limiting nutrient elements. The loss of nitrogen and phosphorus in agricultural systems can cause the eutrophication of natural water bodies. In this paper, a field simulated rainfall experiment was conducted in a typical small watershed of the Danjiang River to study the nutrient loss process of nitrogen and phosphorus in slope croplands subjected to different crops and tillage measures. The characteristics of the runoff process and nutrient migration of different slope treatments were studied, which were the bare-land (BL, as the control), peanut monoculture (PL), corn monoculture (CL), bare land (upper slope) mixed with peanut monoculture (lower slope) (BP), corn and peanut intercropping (TCP), corn and soybean intercropping (TCS), downslope ridge cultivation (BS) slope, and straw-mulched (SC), respectively. The results showed that the runoff of CL, SC, TCS, BS, BP, PL and TCP slope types were 93%, 75%, 51%, 39%, 28%, 12%, and 6% of the those of the bare land, respectively. The total nitrogen concentration in runoff on different slope types decreased in the order of BP > PL > BS > SC > TCP > BL > CL > TCS. The BL was characterized with the highest NRL-TN (the loss of total nitrogen per unit area), with the value of 1.188 kg/hm2, while those of the TCP is the smallest with the value of 0.073 kg/hm2. The total phosphorus concentration in runoff decreasd in the order of BS > BP > PL > BL > TCP > SC > CL > TCS. The PRL-TP (the loss of total phosphorus per unit area) of BL is the largest (0.016 kg/hm2), while those of TCP is the smallest (0.001 kg/hm2). These indicate that the loss of nitrogen is much higer than that of phosphorus. The loss of nitrogen in runoff is dominated by nitrate nitrogen, which accounts for 54.4%–78.9% of TN. Slope croplands in the water source area should adopt the tillage measures of TCP and PL.These measures can reduce 85% of the runoff of nitrogen and phosphorus compared to the bare land. The results may assist in agricultural non-point source pollution control and help promote improved management of the water environment in the Danjiang River’s water source area.

scholarly journals A novel submerged Rotala rotundifolia, its growth characteristics and remediation potential for eutrophic waters

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Chaoguang Gu ◽  
Feifei Li ◽  
Jibo Xiao ◽  
Shuyi Chu ◽  
Shuang Song ◽  
...  
Keyword(s):  
Total Phosphorus ◽  
Nitrogen Concentration ◽  
Biomass Accumulation ◽  
Ammonium Nitrogen ◽  
Phosphorus Concentration ◽  
Nitrogen And Phosphorus ◽  
Overlying Water ◽  
Total Phosphorus Concentration ◽  
Submerged Aquatic Plant ◽  
Nitrogen Contents

Abstract The vegetative growth and remediation potential of Rotala rotundifolia, a novel submerged aquatic plant, for eutrophic waters were investigated on different sediments, and under a range of nitrogen concentrations. Rotala Rotundifolia grew better on silt than on sand and gravel in terms of plant height, tiller number and biomass accumulation. Percent increment of biomass was enhanced at low water nitrogen (ammonium nitrogen concentration ≤10 mg/L). The maximum total nitrogen and total phosphorus removals in the overlying water were between 54% to 66% and 42% to 57%, respectively. Nitrogen contents in the sediments increased with increasing water nitrogen levels, whereas, nitrogen contents in the plant tissues showed no apparent regularity, and the greatest value was obtained at ammonium nitrogen concentration 15 mg/L. Both phosphorus contents in the sediments and tissues of plants were not affected significantly by additional nitrogen supply. Direct nitrogen uptake by plants was in the range of 16% to 39% when total phosphorus concentration was 1.0 mg/L. These results suggested that Rotala Rotundifolia can be used to effectively remove nitrogen and phosphorus in eutrophic waters.

The effect of phosphorus on the growth and chemical composition of some tropical pasture legumes. II. Nitrogen, calcium, magnesium, potassium, and sodium contents

1969 ◽  
Vol 20 (4) ◽  
pp. 675 ◽  
Author(s):  
CS Andrew ◽  
MF Robins
Keyword(s):  
Nitrogen Concentration ◽  
Sodium Concentration ◽  
Dihydrogen Phosphate ◽  
Exchangeable Cation ◽  
Sodium Dihydrogen Phosphate ◽  
Nitrogen And Phosphorus ◽  
Cation Composition ◽  
Pasture Legumes ◽  
Calcium Magnesium ◽  
Phosphate Supply

This paper describes the effect of phosphorus on nitrogen concentration and on the total and individual concentrations of the cations calcium, magnesium, potassium, and sodium in the plant tops of 10 tropical legumes and one temperate legume when grown on two soils of different type, a light-textured solodic soil and a gley soil. Species used were Phaseolus lathyroides, P. atropurpureus, Stylosanthes humilis, Centrosema pubescens, Glycine javanica, Lotononis bainesii, Medicago sativa, Desmodium uncinatum, D. intortum, Vigna luteola, and Leucaena leucocephala. The nitrogen concentrations in the plant tops were increased by phosphorus supply, and good correlations were established between the nitrogen and phosphorus concentrations in the plant tops. When sodium dihydrogen phosphate was used as the source of phosphate, the sodium concentration in V. luteola, M. sativa, and L. bainesii was increased. Other species were not affected. Increasing phosphate supply as monocalcium phosphate had little effect on plant calcium concentration, but brought about an increase of magnesium in P. lathyroides and P. atropurpureus. In the solodic soil particularly, increases in phosphate supply in most species caused reductions in the potassium concentration, partly compensated by increases in the magnesium and calcium concentrations. Concentrations of the cations in the plants reflected the soil exchangeable cation composition. Plant species differed in their cation status. P. atropurpureus and P. lathyroides were relatively high in magnesium, L. bainesii and D. intortum in potassium, V. luteola, L. bainesii, M. sativa, and P. lathyroides in sodium, and C. pubescens and S. humilis in calcium.

Effect of times, height and frequency of defoliation on growth and development of Townsville stylo in pure ungrazed swards at Katherine, N.T

1973 ◽  
Vol 13 (63) ◽  
pp. 389 ◽  
Author(s):  
MJ Fisher
Keyword(s):  
Growth And Development ◽  
Growing Season ◽  
Nitrogen And Phosphorus ◽  
Pod Yield ◽  
Matter Production ◽  
Stylosanthes Humilis ◽  
Townsville Stylo ◽  
One Year ◽  
Complete Fertilizer ◽  
Cutting Height

A one-year experiment was done in the field at Katherine, Northern Territory, to determine the influence of defoliation at different times (January, February, and March) and heights (5, 13 and 20 cm) on the growth and development of Townsville stylo (Stylosanthes humilis) in ungrazed swards grown with complete fertilizer and irrigation. Townsville stylo withstood repeated defoliation at 5 cm provided that cutting started in January, but, when the first defoliation was delayed, single cuts at 5 cm in either February or March killed 82 and 53 per cent of the swards. Defoliation to 5 cm early in the season reduced total cumulative yield by less than 450 kg ha-1, and did not affect pod yield or nitrogen and phosphorus concentrations at the end of the growing season. Immediately after defoliation nitrogen and phosphorus concentrations were reduced, but there was rapid recovery to higher levels with 5-cm and the same levels with 13-cm defoliation. Successive defoliation at 4 3 cm in February and March increased yield of pods. Defoliation at both 5 and 13 cm increased relative growth rate compared with the control and less frequently defoliated treatments. Defoliation to 5 cm each four weeks altered the stand morphology to a dense mat of foliage at cutting height. The ability of Townsville stylo to withstand continued defoliation suggests that sustained grazing during the growing season may be successful in controlling grass weeds vulnerable to grazing without greatly reducing pod yield or total dry matter production of Townsville stylo.

Biomass of Phragmites australis and Effect Factors Analyzing in Zha Long Wetland

2011 ◽  
Vol 393-395 ◽  
pp. 1119-1123
Author(s):  
Tao Zeng ◽  
Hui Huang
Keyword(s):  
Phragmites Australis ◽  
Nitrogen Concentration ◽  
Weight Ratio ◽  
Average Diameter ◽  
Phosphorus Concentration ◽  
Limiting Factor ◽  
Average Height ◽  
Nitrogen And Phosphorus ◽  
Natural Reserve ◽  
Average Biomass

Phragmites australis are the typical vegetation in Zha Long National Natural Reserve. From August 10th to August 21st in 2006, we chose 60 quadrats in 15 sample sites, investigated the reed biomass, height, diameter, water nitrogen and phosphorus concentration. The results are as follow: 1) the average biomass of Phragmites australis models is 2858g•m-2 and the biomass between 15 sample sites is from 2029.0 to 4067.4 g•m-2; 2) the moisture content of Phragmites australis is from 42.95% to 64.95%. The average height of Phragmites australis is 272.47cm, and the average diameter of Phragmites australis is 0.51cm; 3) the NP weight ratio in each sample site concentrate from 9.18 to 15.79. Nitrogen is the most important limiting factor in Phragmites australis vegetation growing while phosphorus is not the limiting factor; 4) the Phragmites australis biomass is restricted by many factors especially water depth and water nitrogen concentration. But the phosphorus concentration in water has irrelativeness with Phragmites australis biomass.

scholarly journals Stoichiometry of Carbon, Nitrogen and Phosphorus in Shrub Organs Linked Closely With Mycorrhizal Strategy in Northern China

2021 ◽  
Vol 12 ◽  
Author(s):  
Shuang Yang ◽  
Zhaoyong Shi ◽  
Menghan Zhang ◽  
Yang Li ◽  
Jiakai Gao ◽  
...  
Keyword(s):  
Nitrogen Concentration ◽  
Northern China ◽  
Nutrient Cycle ◽  
Ecosystem Functions ◽  
Phosphorus Concentration ◽  
Nitrogen And Phosphorus ◽  
Mycorrhizal Status ◽  
N Concentration ◽  
Stems And Leaves ◽  
The Impact

Mycorrhizal strategies include mycorrhizal statuses and mycorrhizal types, which are important reflections of the functional characteristics of ecosystems. The stoichiometry of carbon, nitrogen, and phosphorus in plant organs is an important part of ecosystem functions, which has an important impact on the nutrient cycle of the ecosystem. The concentration of carbon, nitrogen, and phosphorus played a crucial role in ecosystem functioning and dynamics. The purpose of this study is to provide theoretical basis and data support for improving the properties of global terrestrial ecosystems by exploring the impact of mycorrhizal strategies on the stoichiometry of C, N, and P in different shrub organs. In this study, stoichiometric patterns of carbon (C), nitrogen (N) and phosphorus (P) in different shrub organs under different mycorrhizal status or types were analyzed at 725 samples across Northern China. Results showed that in different mycorrhizal status, the highest carbon concentration in shrub organs appeared in the facultatively mycorrhizal (FM) mycorrhizal status, and the highest nitrogen concentration appeared in the Non-mycorrhizal (NM) mycorrhizal status. Under different mycorrhizal types, the nitrogen concentration in the shrub organs under the arbuscular mycorrhiza (AM) mycorrhizal type was the highest, and the phosphorus concentration under the ecto-mycorrhiza (ECM) mycorrhizal type was the highest. In the OM or FM mycorrhizal status, the concentrations of C, N, and P in the stems and leaves increase with the increase of the concentrations of C, N, and P in the roots. In the NM mycorrhizal status, the N concentration in the stems and leaves increases with the increase of the N concentration in the roots. Under AM, AM+ECM, and ECM mycorrhizal type, the concentrations of C, N, and P are closely related in roots, stems and leaves. The content of plant nutrients in different organs is closely related. It turned out that mycorrhizal statuses or types are able to alter the allocation of C, N, and P in different organs, and the relationships of C, N, and P among different organs are able to present different trend with the varying of mycorrhizal statuses or types.

Effect of droughting and chilling on maturation and chemical composition of Townsville Stylo (Stylosanthes humilis)

1971 ◽  
Vol 22 (3) ◽  
pp. 369 ◽  
Author(s):  
CT Gates ◽  
WT Williams ◽  
RD Court
Keyword(s):  
Amino Acids ◽  
Nutrient Content ◽  
Major Effect ◽  
Multivariate Techniques ◽  
Soluble Nitrogen ◽  
Nitrogen And Phosphorus ◽  
Protein Nitrogen ◽  
Stylosanthes Humilis ◽  
Dry Conditions ◽  
Townsville Stylo

The effects of droughting and chilling on maturing Townsville stylo plants was assessed in terms of growth, seed and leaf shed, nitrogen, phosphorus, and amino acid composition. The major effect was due to droughting. Temperature participated as a small temperature-droughting interaction, in that cold reduced growth and increased proline under moist, but not under dry conditions. With droughting under warm conditions seed and leaf shed were increased and the nutrient content of seed was raised, which resulted in more of the plant's nitrogen and phosphorus being lost in these fractions. Droughting increased soluble nitrogen at the expense of protein nitrogen, but the amino acids fell as a proportion of the soluble nitrogen. The interrelations of nine amino acids were examined by multivariate techniques and it was shown that proline and aspartic acid behaved atypically, and that while other amino acids fell, proline increased some 10-fold under drought or cold stress. These effects indicate that soluble nitrogenous components may both increase and change in composition in the maturing plant as a result of stress, so rendering the plant more susceptible under field conditions to leaching or breakdown caused by dew or by slight showers of rain.

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