Plant population dynamics in subterranean clover and murex medic swards. II. Plant population density

1994 ◽  
Vol 45 (4) ◽  
pp. 929 ◽  
Author(s):  
MJ Blumenthal ◽  
RL Ison
Keyword(s):  
Population Density ◽  
Seedling Recruitment ◽  
Subterranean Clover ◽  
Trifolium Subterraneum ◽  
Growing Season ◽  
Plant Population ◽  
Plant Population Dynamics ◽  
Specific Effects ◽  
Matter Production ◽  
Plant Population Density

It is possible that the use of harder-seeded varieties of sub. clover (Trifolium subterraneum) and the recently domesticated murex medic (Medicago murex) may improve annual legume persistence in pasture leys. To determine the mechanisms of production and persistence in these two species, plant population density changes in single seed (sprayed) and naturally regenerating (unsprayed) swards were monitored in four varieties of sub. clover and two lines of murex medic over a three year period at Forbes in central-west N.S.W. Seedling recruitment was very sensitive to soil water and temperature at the time of germination and emergence, particularly in murex medic. Murex recruitment under irrigation was at least four times greater than without irrigation on a germinable seed basis. Irrigation of sub. clover swards did not improve recruitment to the same extent as it did in murex medic. Even the soft seeded cultivars (Junee, Seaton Park and Woogenellup) can regenerate from residual seed in the year following a year in which no seed was set, although there are qualifications for Woogenellup. Plant population density (D) declined over the growing season, despite the specific effects of environment and management; initial plant population density (Di) appears to have the greatest influence on dry matter production over the growing season.

The effect of sodium molybdate mixed in the lime seed pellet on nodulation, nitrogen content, and growth of subterranean clover

1969 ◽  
Vol 9 (39) ◽  
pp. 432 ◽  
Author(s):  
JW Gartrell
Keyword(s):  
Nitrogen Content ◽  
Dry Matter ◽  
Sodium Molybdate ◽  
Subterranean Clover ◽  
Trifolium Subterraneum ◽  
Growing Season ◽  
Combined Nitrogen ◽  
Matter Production ◽  
Clover Seed ◽  
Ground Limestone

Sodium molybdate at l 1/2 oz, 3 oz, and 6 oz mixed with 6 lb ground limestone and pelleted onto 12 lb of Trifolium subterraneum cv. Geraldton inoculated with peat culture markedly reduced clover nodulation, growth, and combined nitrogen production compared with nil sodium molybdate. Mixtures of sodium molybdate l 1/2 oz, 3 oz, and 6 oz with l80 lb superphosphate drilled at 180 lb an acre with 12 lb an acre clover seed inoculated and pelleted with 6 lb ground limestone had no effect on nodulation, increased dry matter production by 70 per cent, and increased nitrogen per acre in tops by 110 per cent compared with nil sodium molybdate. The differences persisted into the second growing season.

Plant population dynamics in subterranean clover and murex medic swards. 3. Effect of pod burial, summer grazing and autumn cultivation on emergence

1996 ◽  
Vol 36 (5) ◽  
pp. 533 ◽  
Author(s):  
MJ Blumenthal ◽  
RL Ison
Keyword(s):  
Soil Water ◽  
Seedling Recruitment ◽  
Subterranean Clover ◽  
Soil Surface ◽  
Trifolium Subterraneum ◽  
Farming Systems ◽  
Plant Population Dynamics ◽  
Eastern Australia ◽  
Ley Farming ◽  
Summer Grazing

Murex medic (Medicago murex Willd.) seedling recruitment is more sensitive to soil water at the time of emergence than subterranean clover (Trifolium subterraneum L.). Murex medic pods normally lay on the soil surface. Shallow burial of pods may be beneficial when soil moisture is marginal for germination and emergence. In addition, the tightly coiled structure of murex medic pods may also act as a barrier to water uptake by the seed. Two methods of burying murex medic pods were investigated in the field: (i) trampling by sheep hooves through summer grazing; and (ii) through light cultivation in autumn. A glasshouse experiment was also conducted to examine the interaction between the length of time that the soil stays moist and pod burial for CD26 and CD53 murex medic and Dalkeith, Junee, Seaton Park and Woogenellup subterranean clover. In the glasshouse, pod burial was important for the attainment of maximum emergence in all genotypes when soil water was limiting. However, pod structure did not appear to have a limiting role in germination and emergence in murex medic. When tested in the field, pod burial by sheep trampling through summer grazing improved emergence in CD26, possibly because the smaller more open pod was more easily trampled than that of CD53. Summer grazing in CD53 and Dalkeith and autumn cultivation in all genotypes did not improve emergence; possible reasons for this are discussed so to is the role of murex medic in ley farming systems in eastern Australia.

scholarly journals The Effect of Plant Population Density on Photosynthesis, Dry Matter Production and 13C-Labeled Distribution in Soybeans

1997 ◽  
Vol 52 (5) ◽  
pp. 875-878 ◽  
Author(s):  
Y. Koesmaryono ◽  
H. Sugimoto ◽  
D. Ito ◽  
T. Sato ◽  
T. Haseba
Keyword(s):  
Population Density ◽  
Dry Matter ◽  
Plant Population ◽  
Dry Matter Production ◽  
Matter Production ◽  
Plant Population Density

Effects of plant population density and rectangularity on the growth and yield of poppies (Papaver somniferum)

1990 ◽  
Vol 115 (2) ◽  
pp. 239-245 ◽  
Author(s):  
B. Chung
Keyword(s):  
Population Density ◽  
Dry Matter ◽  
Plant Density ◽  
Plant Population ◽  
Growth And Yield ◽  
Dry Matter Production ◽  
Matter Production ◽  
Average Wind ◽  
Total Head ◽  
Plant Population Density

SUMMARYGrowth, yield and incidence of lodging of poppies were studied in Tasmania at 10–200 plants/m2 and at nominal rectangularities (within-row: between-row spacing) ranging from 1:1 to 10:1. In 1983/84 and 1988/89, there were asymptotic relationships between plant population density and both total dry-matter production and total head (capsule plus seed) yield at maturity. In 1983/84, a season with above-average wind, the incidence of lodging increased as density increased to > 50 plants/m2; morphine concentration decreased as density increased to > 100 plants/m2. This resulted in parabolic relationships between yield of erect (machine-harvestable) heads and yield of morphine from erect heads with plant density, the maximum morphine yield from erect heads being achieved at 70 plants/m2. In 1988/89, a season with below-average wind, the effects of lodging were less severe at high densities and the components of ‘erect’ yield were adequately fitted by an asymptotic function. Rectangularity of 1:1 gave higher total dry matter production, total head yield, yield of erect heads and morphine yield from erect heads than 4:1 and 10:1. Since calm conditions similar to those of 1988/89 occur only once in every 4 years, growers should be encouraged to establish c. 70 plants/m2. As most commercial crops in Tasmania are drilled in 150–175 mm rows, growing at 70 plants/m2 to maximize the effect of plant density would also approximate to the ideal rectangularity (2:1 in this case).

Effect of plant density and row spacing on the yield of chickpea (cv. Tyson) grown on the Darling Downs, south-eastern Queensland

1989 ◽  
Vol 29 (2) ◽  
pp. 241 ◽  
Author(s):  
DF Beech ◽  
GJ Leach
Keyword(s):  
Population Density ◽  
Seed Yield ◽  
Dry Matter ◽  
Plant Population ◽  
Growth And Yield ◽  
Dry Matter Production ◽  
Row Spacing ◽  
South Eastern ◽  
Matter Production ◽  
Plant Population Density

Growth and yield of chickpea, Cicer arietinum cv. Tyson, were studied at 4 row spacings (180, 360, 530 and 710 mm) and 4 plant population densities (14, 28, 42 and 56 plants m-2) in factorial combination in a wet and a dry growing season on a vertisol at Dalby, south-eastern Queensland. In both years, row spacing had only a small effect on above-ground dry matter production and yield, and there were no significant interactions between row spacing and plant population density. Above-ground dry matter production increased significantly with increase in plant population density for about 120 days after sowing. Seed yield increased significantly from 104 to 126 g m-2 in the drier season (106 mm rain, May-October) with increase in plant population density from 14 to 56 plants m-2. In the wetter season (286 mm rain, May- October), the corresponding trend in yield was from 262 to 287 g m-2. The response was attributed chiefly to larger seed size in the wet year, and higher harvest index in the dry year. We conclude that a density of at least 40 plants m-2 is required to attain maximum seed yield in southeastern Queensland. Although row spacing had no significant effect on yield, our earlier research indicated potential benefits from narrow row spacing, particularly for mechanised crop production.

The effect of varying plant population density on the seed yield of Navy beans (Phaseolus vulgaris)in south-east Enland

1977 ◽  
Vol 88 (3) ◽  
pp. 567-576 ◽  
Author(s):  
D. H. Scarisbrick ◽  
J. M. Wilkes ◽  
R. Kempson
Keyword(s):  
Phaseolus Vulgaris ◽  
Population Density ◽  
Seed Yield ◽  
Plant Density ◽  
Growing Season ◽  
Plant Population ◽  
Population Densities ◽  
Growing Seasons ◽  
Navy Beans ◽  
Plant Population Density

SUMMARYNavy beans were precision drilled in 1973–5 at a range of plant population densities. Within each growing season the density treatments did not influence seed yield, but mean yields differed significantly between years. The results suggest that cultivars similar to Purley King can only be regarded as a reliable break crop in a season such as 1973 which was slightly warmer and drier in mid-summer than average. Although the rate of drying increased with increasing plant density in two of the growing seasons, no practical advantages are proposed.

Effects of plant population density on determinate and indeterminate forms of winter field beans (Vicia faba) 2. Growth and development

1991 ◽  
Vol 116 (3) ◽  
pp. 385-393 ◽  
Author(s):  
C. J. Pilbeam ◽  
P. D. Hebblethwaite ◽  
T. E. Nyongesa ◽  
H. E. Ricketts
Keyword(s):  
Population Density ◽  
Leaf Area ◽  
Plant Population ◽  
Field Bean ◽  
Matter Production ◽  
Competition For Light ◽  
Plant Population Density ◽  
The University ◽  
Field Beans ◽  
Target Plant

SUMMARYIn studies at the University of Nottingham at Sutton Bonington in two consecutive seasons beginning in 1986/87, Bourdon, an indeterminate cultivar, and 858, a determinate selection (provided by Plant Breeding International, Cambridge), were compared under six target plant population densities ranging from 10 to 80 plants/m2.As the season progressed, total dry matter production increased to a maximum and then declined. However, growth rates slowed at pod set because, it is suggested, of the change in the chemical composition of the newly synthesized biomass, from carbohydrate to protein, at that time. Leaf area duration was greater in Bourdon than in 858, especially during pod set, but it bore no relation to seed yield. Specific leaf area was unaffected by competition for light. It is proposed that changes in plant population density affect the competition for assimilates within a plant rather than the competition for light between different plants. Losses of branches and reproductive nodes, with time, are cited as evidence for this. The apparent causes of the lower yield of determinate forms of winter field bean relative to indeterminate forms are discussed.

Adaptation of CERES-Maize model for a better simulation of plant population density effects

2019 ◽  
Vol 238 ◽  
pp. 27-34 ◽  
Author(s):  
R. Cazanga ◽  
J.F. Ledent ◽  
E. von Bennewitz
Keyword(s):  
Population Density ◽  
Plant Population ◽  
Density Effects ◽  
Plant Population Density

Frost damage to winter wheat in the UK: the effect of plant population density

2004 ◽  
Vol 21 (1) ◽  
pp. 105-115 ◽  
Author(s):  
J.M Whaley ◽  
E.J.M Kirby ◽  
J.H Spink ◽  
M.J Foulkes ◽  
D.L Sparkes
Keyword(s):  
Population Density ◽  
Winter Wheat ◽  
Frost Damage ◽  
Plant Population ◽  
Plant Population Density ◽  
The Uk
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