A comparison of the phosphorus nutrition of Australian heath plants and introduced economic plants

1966 ◽  
Vol 14 (2) ◽  
pp. 201 ◽  
Author(s):  
RL Specht ◽  
RH Groves
Keyword(s):  
Native Species ◽  
Trifolium Subterraneum ◽  
Dry Weight ◽  
Phosphorus Fractionation ◽  
Available Phosphorus ◽  
Indigenous Species ◽  
Active Growth ◽  
Low Phosphorus ◽  
Total Dry Weight ◽  
Phosphorus Levels

Dry weight and phosphorus fractionation data are presented for seven species grown over a range of phosphorus levels from 0.Wi to 10.0 p.p.m. in 2 iitres of water culture. As the phosphorus level was established at the beginning of the experiment and not afterwards adjusted, the maximum available phosphorus for each species (six plants per pot) was within the range of 0.3 to 3000 μg, plus seed phosphorus, per plant. The species were representative of two groups: species indigenous to the heath formation (Eucalyptus baxteri, Casuarina pusilla, Acacia suaveolens, and Banksia ornata) and introduced economic species now being grown with fertilizer on the same soils (Pinus radiata, Avena sativa, and Trifolium subterraneum). Results showed that at least one of the economic species, T. subterraneum, was able to absorb phosphorus from nutrient solutions to the same extent as the native species. No difference in growth, as measured by total dry weight, was observed in any species in the nutrient cultures containing less than 30 μg P per plant. 300 μg P per plant produced extra growth in all species except P. radiata, which responded only at 3000 μg P per plant. Nutrient imbalance temporarily decreased growth in all cultures containing 3000 μg P per plant. An important factor in the growth of perennial heath species at low levels of substrate phosphorus is considered to be an increase in the percentage of orthophosphate in the plant at a time of the year when active growth is being made. Other factors, such as the low death-rate of leaves and an efficient means of redistribution of nutrients from senescing leaves, may also be important. The significance of these findings in relation to the growth of the indigenous species in the field is discussed. Species which possess all these characteristics have a decided advantage for survival in low phosphorus environments.

The effect of autotetraploidy in five varieties of subterranean clover (Trifolium subterraneum L.).

1954 ◽  
Vol 5 (3) ◽  
pp. 356 ◽  
Author(s):  
WM Hutton ◽  
JW Peak
Keyword(s):  
Moisture Content ◽  
Dry Matter ◽  
Subterranean Clover ◽  
Trifolium Subterraneum ◽  
Dry Weight ◽  
The Other ◽  
Seed Setting ◽  
Plant Parts ◽  
Green Matter ◽  
Total Dry Weight

Induced autotetraploidy in the Dwalganup variety of subterranean clover (Trifolium subterraneum L.) resulted in total dry weight increases of 60 and 65.5 per cent. at flowering and maturity respectively. In the other four varieties the tetraploids had decreased yields of dry matter compared with the diploids, although the decreases for leaf weights at flowering were nonsignificant in Mount Barker and Tallarook, as was the total dry weight reduction in Tallarook at maturity. There were no significant differences between the diploids and tetraploids in percentage moisture content. When early development was stimulated by growth in a glass-house, the tetraploids of all varieties showed a significant increase in yield of green matter. The level of increased growth was maintained only in Dwalganup, and decreased in other varieties during flowering. An analysis was made of the way in which the different plant parts mere changed by tetraploidy. Where decreased growth occurred, the leaves and stems were coarser. In all varieties a reduced seed-setting followed autotetraploidy, although in Dwalganup the yield of seed per plant was not affected.

Nodule and Plant Development in Stylosanthes humilis H.B.K.: Symbiotic Response to Phosphorus and Sulphur

1974 ◽  
Vol 22 (1) ◽  
pp. 45 ◽  
Author(s):  
CT Gates
Keyword(s):  
Soil Phosphorus ◽  
Effective Strain ◽  
Dry Weight ◽  
Nodule Development ◽  
Nitrogen And Phosphorus ◽  
Relative Growth Rates ◽  
High Phosphorus ◽  
Stylosanthes Humilis ◽  
Low Phosphorus ◽  
Phosphorus Levels

The effect of phosphorus and sulphur on the initiation and subsequent course of development of effective nodulation was determined for young seedlings of Stylosanthes humilis over the period days 1 1 to 26 from sowing. The plants were inoculated with an effective strain of Rhizobium and grown under controlled conditions in a small amount of nitrogen-deficient soil. Phosphorus had a beneficial effect on the initiation of nodules, which were first detected at day 11 in high-phosphorus plants, but not until day 14 in low. Thereafter, nodule development was greatly enhanced by phosphorus, nodule numbers, volumes and dry weights being increased. Nodule relative growth rates were stimulated from 0 . 3 g/g/day at low phosphorus levels to 0 . 7 g/g/day at high phosphorus levels over days 23-26. The nodules became pink earlier, and developed more rapidly as nitrogen-rich organs, in response to phosphorus. This suggested that from the earliest stages, phosphorus not only promoted the development of an increased mass of nodular tissue but also favoured an effective symbiosis. This enhanced nodule development led to greatly stimulated growth, with increasing amounts of total nitrogen and phosphorus in high-phosphorus plants. The assimilation of nitrogen by the whole plant was increased from 17 mg/g nodule dry weightlday at low to 53 mg/g/day with high phosphorus over days 23-26. Sulphur caused an increase in dry weight, but the response to sulphur mainly occurred late in development and was smaller than the response to phosphorus in the young seedlings of this trial.

The influence of temperature and density on the growth of communities of subterranean clover (Trifolium subterraneum L. cv. Mount Barker)

1973 ◽  
Vol 24 (4) ◽  
pp. 479 ◽  
Author(s):  
PS Cocks
Keyword(s):  
Growth Rate ◽  
High Temperature ◽  
Subterranean Clover ◽  
Trifolium Subterraneum ◽  
Dry Weight ◽  
Plant Size ◽  
Area Index ◽  
Influence Of Temperature ◽  
Total Dry Weight ◽  
Increasing Temperature

The influence of temperature on the growth of high and low density communities of subterranean clover (Trifolium subterraneum L. cv. Mount Barker) was studied at four temperatures ranging from 12�C day/7�C night to 27�C day/22�C night. The response to temperature depended on leaf area index (LAI). When the LAI was low (0.2), growth rate increased with increasing temperature to a maximum at 22� day/ 17�C night. This agreed with the temperature response of single plants of the same species previously reported. However, when the LAI was 3 the growth rate was not influenced by temperature within the range tested. At a still higher value of LAI (5.5), the response in growth became negative with increasing temperature, communities at the highest temperature growing at only half the rate of those at the lowest. The frequency distribution of plant size in the dense communities was measured, at eight times during the experiment. The distribution was influenced by both temperature and the total dry weight of the community. At low temperature it was approximately symmetrical, but at high temperature it rapidly became asymmetric as total dry weight increased, the amount of skewness being greatest at the highest temperature and dry weight. Plant death was greatest at the high temperature. The communities were divided into five equally populated groups of ascending plant size. At high temperature the largest plants increased in size throughout the experiment, but each of the groups of smaller plants reached a maximum size, subsequently losing weight. At lower temperatures only the groups of smaller size lost weight, the number of groups losing weight depending on temperature. The distribution data were used to try to explain the interaction between temperature and LAI. It was proposed that community growth rate was best when canopy cover was complete and the distribution of plant weight was not strongly skewed.

Effects of Chronic Ozone Exposure on the Growth of Trifolium subterraneum and Trifolium repens

1981 ◽  
Vol 8 (5) ◽  
pp. 405 ◽  
Author(s):  
DC Horsman ◽  
AO Nicholls ◽  
DM Calder
Keyword(s):  
Trifolium Subterraneum ◽  
Dry Weight ◽  
Plant Part ◽  
Ozone Exposure ◽  
Rapid Decline ◽  
Relative Growth ◽  
Area 6 ◽  
Leaf Necrosis ◽  
Net Assimilation ◽  
Total Dry Weight

Plants of Trifolium subterraneum and T. repens were exposed to 9 parts per hundred million ozone for 4 h per day, 5 days per week for 5 weeks. Leaf necrosis was apparent after the first week of exposure and this was followed by the death of some leaves and stems. At the end of the exposure, significant reductions were found in total dry weight (30-40%), plant part dry weight and leaf area (ͭ6 30%). Ozone caused a rapid decline in relative growth rate which was related to a reduction in net assimilation rate.

Distribution of zinc and copper in seedlings of subterranean clover (Trifolium subterraneum L.) in solution culture

1956 ◽  
Vol 7 (6) ◽  
pp. 495 ◽  
Author(s):  
DS Riceman ◽  
GB Jones
Keyword(s):  
Dry Matter ◽  
Subterranean Clover ◽  
Trifolium Subterraneum ◽  
Dry Weight ◽  
Solution Culture ◽  
Rapid Decline ◽  
Trifoliate Leaf ◽  
Plant Parts ◽  
Total Dry Weight ◽  
Substantial Change

Changes in the distribution of zinc, copper, and dry matter in seedlings of Trifolium subterraneum L. var. Bacchus Marsh grown in solution cultures which were supplied with copper but not with zinc have been traced during the first 40 days after germination. Increase in total dry weight was accompanied by a rapid decline in the concentration of zinc in the plant parts examined. Symptoms of zinc deficiency were recognizable in the third trifoliate leaf by the time the leaflets opened, 33 days after germination. At that time the concentration of zinc in leaf plus petiole had fallen to 14 p.p.m. in the dry matter. There was a continual net loss of zinc from the cotyledons. A marked increase in the amount of copper present in roots, and in leaf plus petiole, occurred soon after the addition of copper to the cultures 20 days after germination, but no substantial change was observed in the amount of copper present in the cotyledons or in the hypocotyl plus growing point. These latter tissues had previously lost small amounts of copper.

BIOASSAY OF PROLACTIN

1969 ◽  
Vol 60 (1) ◽  
pp. 91-100 ◽  
Author(s):  
Charles S. Nicoll
Keyword(s):  
Epithelial Cells ◽  
Lipid Content ◽  
Dry Weight ◽  
Fat Content ◽  
Assay Sensitivity ◽  
Mucosal Epithelium ◽  
Wet Weight ◽  
Total Dry Weight

ABSTRACT The response of the pigeon crop-sac to systemically acting prolactin (injected subcutaneously) was evaluated by measuring the wet weight of the responsive lateral lobes of the organ and by determining the dry weight of a 4 cm diameter disc of mucosal epithelium taken from one hemicrop. Of several different injection schedules tested, administration of prolactin in four daily injections was found to yield optimal responses. When compared with a graded series of prolactin doses, measurement of the mucosal dry weight proved to be a better method of response quantification than determination of the crop-sac wet weight with respect to both assay sensitivity and precision. The submucosal tissue of the crop-sac was estimated to constitute about 64 % of the total dry weight of the unstimulated organ and it was found to be relatively unresponsive to prolactin stimulation in comparison with the mucosa. The lipid content of the mucosal epithelium was determined using unstimulated crop-sacs or tissues which showed varying degrees of prolactin-induced proliferation. The fat content of the mucosal epithelial cells increased only slightly more rapidly than the dry weight or the defatted dry weight of the mucosa. Suggestions are made for the further improvement of the systemic crop-sac assay for prolactin.

Impact of an Open Trellis on Canopy Growth, Light Interception, Yield, and Leaf Physiology of Red Raspberry (Rubus idaeus)

HortScience ◽  
1998 ◽  
Vol 33 (3) ◽  
pp. 468b-468
Author(s):  
Stephen F. Klauer ◽  
J. Scott Cameron ◽  
Chuhe Chen
Keyword(s):  
Leaf Area ◽  
Total Nitrogen ◽  
Dry Weight ◽  
Light Interception ◽  
Rubus Idaeus ◽  
Above Ground Biomass ◽  
Red Raspberry ◽  
Leaf Physiology ◽  
Total Dry Weight ◽  
Upper Third

After promising results were obtained with an open-style split trellis (two top wires) in its initial year, two new trials were established in 1997 in northwest (Lynden) and southwest (Woodland) Washington. For the split trellis, actual yields were 33% (machine-picked 1/2 season) and 17% (hand-picked) greater, respectively, for the two locations compared to the conventional trellis (one top wire). In Woodland, canes from the split trellis had 33% more berries, 55% more laterals, 69% more leaves, and 25% greater leaf area compared with the conventional trellis. Greatest enhancement of these components was in the upper third of the canopy. Laterals were also shorter in this area of the split canopy, but there was no difference in average total length of lateral/cane between trellis types. Total dry weight/cane was 22% greater in the split trellis, but component partitioning/cane was consistent between the two systems with fruit + laterals (43%) having the greatest above-ground biomass, followed by the stem (30% to 33%) and the leaves (21% to 22%). Measurement of canopy width, circumference, and light interception showed that the split-trellis canopy filled in more quickly, and was larger from preanthesis through postharvest. Light interception near the top of the split canopy was 30% greater 1 month before harvest with 98% interception near the top and middle of that canopy. There was no difference between the trellis types in leaf CO2 assimilation, spectra, or fluorescence through the fruiting season, or in total nitrogen of postharvest primocane leaves.

scholarly journals Dietary metabolizable energy, digestible lysine, available phosphorus levels and exogenous enzymes affect broiler chicken performance

animal ◽  
2021 ◽  
Vol 15 (5) ◽  
pp. 100206
Author(s):  
P. Cozannet ◽  
R. Davin ◽  
M. Jlali ◽  
J. Jachacz ◽  
A. Preynat ◽  
...  
Keyword(s):  
Broiler Chicken ◽  
Metabolizable Energy ◽  
Available Phosphorus ◽  
Exogenous Enzymes ◽  
Phosphorus Levels

scholarly journals Impact of Different Water Management Regimes on the Growth, Productivity, and Resource Use Efficiency of Dry Direct Seeded Rice in Central Punjab-Pakistan

Agronomy ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 1151
Author(s):  
Sadam Hussain ◽  
Saddam Hussain ◽  
Zubair Aslam ◽  
Muhammad Rafiq ◽  
Adeel Abbas ◽  
...  
Keyword(s):  
Grain Yield ◽  
Hybrid Rice ◽  
Water Productivity ◽  
Dry Weight ◽  
Cost Ratio ◽  
Yield Attributes ◽  
Benefit Cost Ratio ◽  
Direct Seeded ◽  
Total Dry Weight ◽  
Benefit Cost

Dry direct-seeded rice has been shown to save irrigation water and labor. Nonetheless, irrigation management in dry direct-seeded rice has received very little attention. Here, we examined the potential of different irrigation regimes: aerobic rice (AR), alternate wetting and drying (AWD) and continuous flooding (CF) in dry direct-seeded rice cultivation on two rice cultivars (Pride-1 (hybrid indica) and NB-1 (inbred indica)). Growth, yield attributes, grain yield, total water input, water productivity and benefit cost ratio were measured. Our results showed that AR saved 11.22 and 28.40%, and 5.72 and 32.98% water compared with AWD and CF during 2018 and 2020, respectively. There was a significant difference in grain yield among treatments and cultivars. AWD and CF produced statistically same total dry weight and grain yield, while AR reduced the total dry weight by 31.34% and 38.04% and grain yield by 34.82% and 38.16% in comparison to AWD and CF, respectively, across the years. Except for 1000-grain weight and harvest index in AWD and CF, further differences in total dry weight and grain yield among irrigation treatments were primarily correlated with variations in yield attributes. Among the cultivars, hybrid rice performed better than inbred rice. Over the two-year period, hybrid rice increased total dry weight, grain yield, and water productivity by 9.28%, 13.05%, and 14.28%, respectively, as compared to inbred rice. Regarding water productivity (WP), the maximum percentage (40.90 and 26.53%) was recorded for AWD compared to AR and CF. Among cultivars, more water productivity (14.28%) was calculated for hybrid rice than inbred one. Chlorophyll and carotenoid contents, leaf area index and crop growth rate contributed to higher grain yield of hybrid rice under AWD and CF. In contrast to WP, the maximum benefit cost ratio was estimated to be higher for CF than that of AR and AWD. For the cultivars, the maximum value (2.26 in 2018 and 2.32 in 2020) was calculated for hybrid rice compared with the inbred one. In conclusion, these results suggests that AWD with maximum WP and CF with maximum BCR could be more efficient approaches than AR. Under CF, hybrid rice cultivars with higher yield and yield-related attributes, WP and BCR performed better.

Effects of Temperature and CO2Concentration on the Growth of Cotton (Gossypium hirsutum), Spurred Anoda (Anoda cristata), and Velvetleaf (Abutilon theophrasti)

Weed Science ◽  
1988 ◽  
Vol 36 (6) ◽  
pp. 751-757 ◽  
Author(s):  
David T. Patterson ◽  
Maxine T. Highsmith ◽  
Elizabeth P. Flint
Keyword(s):  
Dry Matter ◽  
Dry Weight ◽  
Net Assimilation Rate ◽  
Assimilation Rate ◽  
Short Term ◽  
Leaf Weight ◽  
Matter Production ◽  
Total Plant ◽  
Net Assimilation ◽  
Total Dry Weight

Cotton, spurred anoda, and velvetleaf were grown in controlled-environment chambers at day/night temperatures of 32/23 or 26/17 C and CO2concentrations of 350 or 700 ppm. After 5 weeks, CO2enrichment to 700 ppm increased dry matter accumulation by 38, 26, and 29% in cotton, spurred anoda, and velvetleaf, respectively, at 26/17 C and by 61, 41, and 29% at 32/23 C. Increases in leaf weight accounted for over 80% of the increase in total plant weight in cotton and spurred anoda in both temperature regimes. Leaf area was not increased by CO2enrichment. The observed increases in dry matter production with CO2enrichment were caused by increased net assimilation rate. In a second experiment, plants were grown at 350 ppm CO2and 29/23 C day/night for 17 days before exposure to 700 ppm CO2at 26/17 C for 1 week. Short-term exposure to high CO2significantly increased net assimilation rate, dry matter production, total dry weight, leaf dry weight, and specific leaf weight in comparison with plants maintained at 350 ppm CO2at 26/17 C. Increases in leaf weight in response to short-term CO2enrichment accounted for 100, 87, and 68% of the observed increase in total plant dry weight of cotton, spurred anoda, and velvetleaf, respectively. Comparisons among the species showed that CO2enrichment decreased the weed/crop ratio for total dry weight, possibly indicating a potential competitive advantage for cotton under elevated CO2, even at suboptimum temperatures.

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