The responses to defoliation of two strains of subterranean clover, differing in growth habit, when grown in swards

1980 ◽  
Vol 31 (1) ◽  
pp. 77 ◽  
Author(s):  
RC Rossiter ◽  
WJ Collins
Keyword(s):  
Growth Habit ◽  
Total Yield ◽  
Initial Density ◽  
Subterranean Clover ◽  
Daily Maximum ◽  
Low Density ◽  
Compact Growth ◽  
Effective Yield ◽  
Principal Finding ◽  
Cutting Height

Dense swards of two strains of T. subterraneum-herein referred to as C and P-were compared at two heights of cutting-1.5 cm (low) and 5.0 cm (high)-and two frequencies of defoliation- 1-weekly (frequent) and 4- or 5-weekly (infrequent). Strain C has smaller leaves than P and a compact, in contrast to a lax, growth habit. The swards (initial density of c. 25 plants/dm2) were grown in boxes, out of doors, at Perth from 27 April to 20 September. Mean daily solar radiation varied from c. 10 to 16 MJ/m2 and average daily maximum and minimum temperatures were c. 20� and 10�C respectively. The principal finding was that under defoliation stress (i.e. low cutting) strain C yielded more than P, whereas at a lower level of stress (high cutting) there was usually little if any difference between these strains. This effect was established for the most part before the first harvest, at day 55; thereafter, with continued defoliation stress, strain P appeared to worsen slightly relative to C. The results provide support for the view that strains with a compact growth habit are less susceptible to defoliation (or grazing) stress than taller strains of lax growth habit. Generally, the total yield of tops and also the effective yield (as cut and removed material) decreased when cutting height was lowered. Also, infrequent cutting increased effective yield, particularly under low density (four plants/dm2) as observed in an ancillary experiment.

AN EVALUATION OF VARIETAL CHARACTERISTICS OF ORCHARDGRASS (DACTYLIS GLOMERATA L.) SUBJECTED TO A SILAGE-PASTURE TYPE OF UTILIZATION

1961 ◽  
Vol 41 (3) ◽  
pp. 653-663
Author(s):  
W. E. P. Davis
Keyword(s):  
Dry Matter ◽  
Growth Habit ◽  
Total Yield ◽  
Early Maturity ◽  
Main Determinant ◽  
Fall Dormancy ◽  
General Adaptation ◽  
Maturity Class ◽  
Regional Adaptation ◽  
Dactylis Glomerata L

A study was conducted over 3 harvest years to evaluate the importance of maturity classification, tillering, and fall dormancy in relation to yield of dry matter, per cent protein and yield of protein, and regional adaptation of 40 orchardgrass varieties subjected to a silage-pasture type of utilization. Using head emergence (silage stage) as the criterion, five maturity classes were established: very early, early, medium, late, very late. Early maturity was positively associated with total yield, but there was no relation between maturity and per cent protein, tillering, or fall dormancy. Total yield of dry matter was the main determinant of protein yield. Tillering was not associated with yield of dry matter or per cent protein but was associated with fall greenness. Fall dormancy was positively associated with prostrate fall growth habit. Individual varieties displaying desirable agronomic characteristics were found within every maturity class. However, the leading varieties with respect to total yield of dry matter and protein per acre were from the medium maturity class. The medium maturity class displayed the best seasonal distribution of dry matter and general adaptation.

The influence of maturity grading on total yield and seed production in strains of Trifolium subterraneun L. grown as single plants and in swards

1959 ◽  
Vol 10 (3) ◽  
pp. 305 ◽  
Author(s):  
RC Rossiter
Keyword(s):  
Soil Moisture ◽  
Seed Production ◽  
Plant Density ◽  
Total Yield ◽  
Subterranean Clover ◽  
Reverse Situation ◽  
Production Pattern ◽  
Seed Yields ◽  
The Relationship ◽  
Early Strain

A large number of strains of subterranean clover was grown as single plants and in swards in a series of 1-year experiments. The relationship between the interval from seeding to flowering ("maturity grading") and the production pattern varied according to plant density. In the case of single plants, both total yields and seed yields increased linearly with increasing maturity grading. With swards, on the other hand, total yields showed scarcely any relation to increasing maturity grading – there was a slight decline, in fact – while seed production fell rapidly. Hence the early strain Dwalganup gave the lowest seed yields as single plants, but the highest seed yields in swards, whereas the reverse situation held for the late strains Wenigup and Tallarook. The main factor responsible for the differences in these production patterns was considered to be available soil moisture supply. It was shown that in the few cases where soil moisture was severely limiting in spring for single plants, yields levelled off (and seed yields even declined) at higher maturity gradings. Three points are discussed at some length: the influence of environment on the seed yield of strains grown as single plants, the effect of plant density on the ratio seed weight/total weight, and production in relation to maturity grading in swards.

Shoot growth on lucerne plants cut at different heights

1970 ◽  
Vol 21 (4) ◽  
pp. 583 ◽  
Author(s):  
GJ Leach
Keyword(s):  
Medicago Sativa ◽  
Dry Matter ◽  
Shoot Growth ◽  
Total Yield ◽  
Extension Growth ◽  
Medicago Sativa L ◽  
Cutting Height ◽  
Two Stages

Lucerne (Medicago sativa L.) plants grown to two stages of maturity were cut at 2, 5, or 10 cm above the crown. In addition, the leaf on the stubble and on basal shoots was either removed or retained. The change in the number and size of the regrowth shoots growing from different heights above the crown, and the total yield of dry matter, were observed for 4 weeks after cutting. Nearly all the regrowth shoots arose from very near to the crown, either on the crown itself or from within the first 2 cm above it, so that cutting at higher levels increased shoot numbers only slightly. Also most of the shoots arising from near the crown resumed extension growth earlier, and therefore grew larger, than the shoots arising from higher positions. In general the growth of shoots from one stubble segment was not influenced by whether segments were still present above. Increasing the cutting height above 2 cm consequently produced little effect on the yield of dry matter 2 and 4 weeks after cutting. Retaining stubble leaf and basal shoot leaf increased the shoot yield 2 and 4 weeks later, because the basal shoots resuming growth first grew larger than those on plants from which leaves were removed. The effect of retaining leaves was independent of the stage of maturity when the plants were cut and of the cutting height.

Effect of timing of forage conservation on forage yield and quality, seed yield and seedling regeneration of four subterranean clover (Trifolium subterraneum) cultivars

2008 ◽  
Vol 48 (8) ◽  
pp. 1133 ◽  
Author(s):  
B. S. Dear ◽  
B. F. Hackney ◽  
G. M. Dyce ◽  
C. A. Rodham
Keyword(s):  
Seed Yield ◽  
Seed Set ◽  
Subterranean Clover ◽  
Trifolium Subterraneum ◽  
Forage Yield ◽  
Seedling Regeneration ◽  
Yield And Quality ◽  
Cutting Height ◽  
Seed Yields ◽  
Forage Yields

Swards of four cultivars of subterranean clover (Trifolium subterraneum L.) were cut at three different times to determine the effect on forage yield and quality, seed set and seedling regeneration in two successive seasons in southern New South Wales. The four cultivars of subterranean clover (Seaton Park LF, Junee, Goulburn and Clare) were cut on 23–25 September (early cut), 8–10 October (mid cut) or 22–23 October (late cut), to simulate an early silage, late silage or hay cut. Additional treatments imposed included either grazing or leaving the regrowth after cutting and raising the cutting height from 3 to 6 cm. Forage yields ranged from 3.5 to 9.3 t dry matter (DM)/ha in the first year and from 2.0 to 5.9 t DM/ha in the second year. Herbage yield was influenced by both cultivar and harvest time with the highest yields achieved with the mid cut. Lower forage yields at the later cut were attributed to losses due to respiration and decay under dense leaf canopies. Changes in forage quality were consistent across both years, with in vivo DM digestibility declining from 76–79% to 69–70% as cutting time was delayed. Crude protein fell from 22–24% to 14–17% over the same period, depending on cultivar. Seed yields in both years were influenced by both cutting time and cultivar with a positive relationship (R2 = 0.45–0.61) between herbage present in late spring after a period of regrowth and subsequent seed yield. The early flowering cultivar Seaton Park LF had the highest seed yield in both years and the more erect cultivar Clare had the lowest. Seed yields declined with later cutting time but increased by an average of 39% when the cutting height was raised from 3 to 6 cm. Seedling regeneration reflected seed yield responses with the largest seedling regeneration occurring in treatments cut early. The study found that forage conservation in early October is likely to yield more and be of higher quality than swards cut later in the season. Seed set is greatly reduced by all cutting strategies to levels unprofitable for seed harvesting but may be adequate for pasture regeneration.

Dry matter production from irrigated winter forage crops in the Murrumbidgee Irrigation Area

1977 ◽  
Vol 17 (89) ◽  
pp. 1004 ◽  
Author(s):  
DL Michalk ◽  
PA Witschi
Keyword(s):  
Dry Matter ◽  
New South ◽  
Total Yield ◽  
Subterranean Clover ◽  
Forage Crops ◽  
Potential Production ◽  
Potential Productivity ◽  
South Wales ◽  
Matter Production ◽  
Consequent Reduction

Between 1962 and 1964, 4 experiments were conducted at Leeton, New South Wales, Australia to examine the potential productivity of a range of irrigated winter forage crops in providing useful feed during the period of shortage in late autumn and early winter. In addition, the effects of sowing rate were examined for sowings using (a) prepared seedbeds or (b) sod-seeding into existing subterranean clover/Lolium rigidum cv. Wimmera pastures. DM yields at 74, 109, 144 or 173 days from sowing were compared with a subterranean clover/ryegrass control. Of the spp. evaluated the cereals were the most consistent both for initial production and subsequent regrowth. For the cruciferous spp. early cutting (100 days after sowing) proved detrimental to subsequent production, reducing the contribution of the sown spp. to 3% DM. Although the low proportion of the leguminous forages limited their potential production, they increased pasture quality relative to the clover/ryegrass control. DM production of wheat and rape increased with increasing sowing rate on (a) but for turnips there was a yield decline with increased sowing rate. Oats showed no response to sowing rate on (a), but increasing the sowing rate on (b) plots increased the proportion of oats in the pasture, although there was a consequent reduction in total yield. Increases in the contribution made by wheat to total yield as a result of increased sowing on (b) plots were small.

scholarly journals LONG DAYS PROMOTE FLOWERING OF ARMERIA MARITIMA

HortScience ◽  
1992 ◽  
Vol 27 (6) ◽  
pp. 575e-575
Author(s):  
J.T. Lehmann ◽  
M.L. Albrecht
Keyword(s):  
Cold Storage ◽  
Growth Habit ◽  
Leaf Length ◽  
Plant Production ◽  
Night Temperature ◽  
Potted Plant ◽  
Compact Growth ◽  
Armeria Maritima ◽  
Vegetatively Propagated Plants ◽  
Short Days

Armeria maritima was studied to provide guidelines for flowering potted plant production. Seed and vegetatively propagated plants were exposed to 9-hr, 13-hr, or 17-hr photoperiods. Flowering was enhanced under the 13-hr and 17-hr photoperiods. Peduncle and leaf length were shorter, and plants were more compact under short days (SD, 9-hr photoperiod) than under long days (LD). When grown under SDs then moved at monthly intervals to LDs, the degree to which the compact growth habit (CH) was expressed was dependent upon the length of exposure to SDs. Plants with the CH produced fewer inflorescences than full growth habit plants. Plants held in cold storage (4C) flowered more profusely under LDs, but had a delay in flowering. There was more uniform flowering for plants held in cold storage than those held in a cool greenhouse (7C night temperature).

scholarly journals Potassium Application and Leaf Sufficiency Level for Fresh-market Tomatoes Grown on a Midwestern United States Fine-textured Soil

2006 ◽  
Vol 16 (2) ◽  
pp. 247-252 ◽  
Author(s):  
H.G. Taber
Keyword(s):  
Growth Habit ◽  
Total Yield ◽  
Fruit Size ◽  
Size Difference ◽  
Fresh Market ◽  
Marketable Yield ◽  
Leaf Petiole ◽  
Indeterminate Growth Habit ◽  
Loam Soil ◽  
Marketable Fruit

Tomato (Lycopersicon esculentum) response to potassium (K) fertilization on a well-drained, central Iowa loam soil testing low in exchangeable K was evaluated over a 3-year period. Each year the experimental design was a factorial, split-plot randomized complete block with K rate as the whole unit (0 to 332 lb/acre). The subunit was cultivar, either `Mountain Spring' (determinate growth habit) or `Jet Star' (indeterminate growth habit). Fruit harvest began the first week of August and continued weekly for 5 to 8 weeks. For all years there was a significant K rate and cultivar effect for all parameters, but no interaction except for marketable fruit size and unmarketable fruit produced. Increasing the K rate to 103 lb/acre increased fruit size of both cultivars to a maximum of 8.9 oz, but year accounted for greater fruit size difference than the choice of cultivar. Maximum marketable yield for both cultivars occurred at 220 lb/acre K with `Jet Star' producing 13% more fruit than `Mountain Spring', 359 vs. 319 cwt/acre, respectively. Cullage was high, mostly as a result of blotchy ripening disorders, with `Jet Star' consistently producing more culls than `Mountain Spring'. Increasing K rate did not reduce the percentage of culls, which remained constant at about 29% of total yield. Whole-leaf K and leaf petiole sap K levels linearly increased with additional K rate for the two sample periods at flowering and mid-harvest. The whole-leaf K sufficiency level for both cultivars at the flowering stage of growth was determined to be 3.15% and dropped to 1.30% K by mid-harvest. Critical petiole leaf sap K values (using a dilution of 1:1 sap to water) could not be determined at flowering, but at mid-harvest the critical value was about 2200 to 2800 ppm K.

scholarly journals Performance of Pillar and Upright Form Peach Trees Grown in a Central Leader or Multiple Leader Orchard System at Various Planting Densities

HortScience ◽  
2004 ◽  
Vol 39 (4) ◽  
pp. 815A-815
Author(s):  
Stephen Miller* ◽  
Ralph Scorza
Keyword(s):  
Fruit Quality ◽  
Growth Habit ◽  
Growing Season ◽  
Row Spacing ◽  
Low Density ◽  
Four Seasons ◽  
Growth Habits ◽  
Time Required ◽  
Peach Trees ◽  
Plot Design

Peach trees with a pillar (P) (columnar) or upright (UP) growth habit were planted at four in-row spacings (1.5, 2.0, 4.0, and 6.0 m) in 1999 and trained to a central leader or multiple leader system to evaluate their performance in an orchard environment. A standard (S) form peach cultivar (`Harrow Beauty') was included for comparison. In this replicated study using a split-split-split plot design, one-half of the trees were summer pruned (SP) 6 weeks before harvest in each growing season from 2001 to 2003. Growth habit, tree spacing, and SP had a significant effect on tree growth and time necessary for dormant pruning. Growth habit and spacing also affected time required to summer prune. Total pruning time for all growth habits was significantly greater for SP trees compared to non-SP trees. Cumulative yields per tree were greater for UP and S habit trees than P trees over the first four seasons. Per tree yields increased as the in-row spacing increased but were decreased slightly by SP. UP trees consistently produced larger size fruit than P or S trees. Potential yields per ha and pruning times based on projected best tree spacings will be presented. UP form trees provide a good transition for growers going from low-density to high-density peach systems, with significant advantages in yield and fruit quality.

scholarly journals Spray and Drench Treatments of Paclobutrazol Influence Growth of Dissotis and Tibouchina

HortScience ◽  
2015 ◽  
Vol 50 (10) ◽  
pp. 1514-1517
Author(s):  
Susan M. Hawkins ◽  
John M. Ruter ◽  
Carol D. Robacker
Keyword(s):  
Adverse Effects ◽  
Plant Growth ◽  
Plant Growth Regulator ◽  
Growth Habit ◽  
Dry Weight ◽  
Spray Application ◽  
Compact Growth ◽  
Nursery Production ◽  
Growth Habits ◽  
Open Growth

Dissotis rotundifolia (Sm.) Triana and Tibouchina fothergillae ×pilosa are members of the Melastomataceae family with high ornamental potential. The growth habits of these species are not ideal for nursery production or shipping. D. rotundifolia grows rapidly and needs frequent pruning. T. fothergillae ×pilosa has an open growth habit and could benefit from a more compact form. The effect of the plant growth regulator (PGR) paclobutrazol on D. rotundifolia and T. fothergillae ×pilosa was assessed to determine whether it could produce plants with a more compact growth habit. Paclobutrazol was applied as a drench and a spray. Drench application was more effective in reducing the growth of both species. Spray application was effective in reducing the growth of D. rotundifolia but was not effective on T. fothergillae ×pilosa. Neither drench nor spray application delayed or reduced flowering in D. rotundifolia. T. fothergillae ×pilosa did not flower during the study. For both D. rotundifolia and T. fothergillae ×pilosa, neither drench nor spray application had an effect on root dry weight. Low-to-medium dosages were effective at controlling plant growth in D. rotundifolia and T. fothergillae ×pilosa without adverse effects on plants. Drench treatments have more persistent effects on plant growth than spray treatments.

Lucerne, phalaris, and wallaby grass in short-term pasture phases in two eastern Australian wheatbelt environments. 1. Importance of initial perennial density on their persistence and recruitment, and on the presence of weeds

2007 ◽  
Vol 58 (2) ◽  
pp. 113 ◽  
Author(s):  
B. S. Dear ◽  
J. M. Virgona ◽  
G. A. Sandral ◽  
A. D. Swan ◽  
B. A. Orchard
Keyword(s):  
Plant Density ◽  
Seedling Recruitment ◽  
Initial Density ◽  
Basal Area ◽  
Subterranean Clover ◽  
Trifolium Subterraneum ◽  
Annual Rainfall ◽  
Curvilinear Relationship ◽  
Initial Population ◽  
South Wales

The influence of initial plant density on the changes in the populations of 3 perennial pasture species, lucerne (Medicago sativa L.), wallaby grass (Austrodanthonia richardsonii (Cashm.) H.P. Linder), and phalaris (Phalaris aquatica L.), over a 3-year pasture phase was examined in the wheatbelt of southern New South Wales. The perennials were sown at 5 rates in combination with subterranean clover (Trifolium subterraneum L.) at 2 locations, Kamarah [430 mm average annual rainfall (a.a.r.)] and Junee (550 mm a.a.r). The range in initial plant populations for lucerne, phalaris, and wallaby grass was 4–74, 8–94, and 2–20 plants/m2, respectively, at Kamarah and 11–120, 9–149, and 6–48 plants/m2 at Junee. When sown at higher densities, the density of lucerne and phalaris declined curvilinearly over the 3 years at both sites. At the 3 lower densities, phalaris populations remained constant at both sites. Lucerne, in contrast, declined over all densities at both sites except at the lowest density at the wetter site (Junee). The rate of decline in lucerne was negatively related (R2 = 0.75) to initial density at Junee, but not at Kamarah. The density of the native grass, wallaby grass, increased with time at both sites through seedling recruitment. The invasion of experimental plots by the summer weed Eragrostis cilianensis (All.) Vign. ex Janchen (stinkgrass) was restricted by lucerne and phalaris, with a negative curvilinear relationship between perennial density and E. cilianensis seedlings in both environments (R2 = 0.65–0.70). In contrast, wallaby grass was ineffective at suppressing E. cilianensis. By the third year, phalaris had significantly higher herbage yields in spring than lucerne and wallaby grass at both sites and phalaris yield was independent of density. Lucerne yields at this time increased with density only at the wetter site (R2 = 0.64), but wallaby grass yields responded to increasing density at both sites (R2 = 0.27–0.59). The experiment demonstrated that establishing higher initial perennial populations of lucerne and phalaris, which did not recruit during the experiment, will result in the maintenance of higher populations over the life of a 3–4 year pasture phase despite proportionally higher rates of plant loss. The size of the initial population was less critical for wallaby grass, which was able to increase in density through recruitment. High initial populations are likely to be an advantage for suppressing weeds in swards of perennial species with limited ability to increase their basal area, such as lucerne and wallaby grass, but will be less beneficial for species such as phalaris, which can compensate by greatly increasing its basal area at lower densities.

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