The influence of sowing rate and row spacing on the plant density and yield of red beet

1985 ◽  
Vol 104 (3) ◽  
pp. 615-624 ◽  
Author(s):  
L. R. Benjamin ◽  
R. A. Sutherland ◽  
D. Senior

SummaryThree experiments examined the effects of sowing rate and between-row spacing on the plant density and yield of red beet.The proportion of seeds which produced mature plants decreased when the mean distance to the nearest neighbour was less than 5 cm. In these experiments, this distance was governed by within-row spacing. Thus, plots with narrow-spaced rows achieved a higher plant density than those with wide-spaced rows, when sown with the same weight of seed.Total yield of beet per unit area decreased with increasing plant density. Maximum yields per unit area of small beet were achieved at high plant densities, whereas maximum yields of large beet were achieved at low plant densities. The effect of between-row spacing on yield was much smaller than that of density, and was important only for crops harvested early. Shoot yield per unit area was measured in two experiments and was not affected by row spacing in either. Shoot yield was not affected by plant density in one experiment, but, in the other, tended to a maximum value with increasing plant density.

HortScience ◽  
2003 ◽  
Vol 38 (4) ◽  
pp. 520-523 ◽  
Author(s):  
V.M. Russo

There is little known about how cultural methods affect yields of nonpungent jalapeño peppers (Capsicum annuum L.). Seedlings of the nonpungent jalapeño peppers `Pace 103', `Pace 105', `Pace 108', `Dulce', and `TAM Sweet2', as well as the pungent jalapeño peppers `Delicias' and `TAM Jalapeño1', used for comparison, were grown in a greenhouse with either one or two seedlings per cell in transplant trays. Transplanting to the field was in mid-April and mid-June of 2000 and 2001. In-row spacing was 0.46 m between transplanting sites. Density was varied by placing either one or two seedlings at a transplant site with resultant plant densities of 24,216 or 48,432 plants/ha. Marketable and cull yields, on a per hectare basis, were determined. In both years there were more fruit produced, and higher yields (25+% greater), at the higher plant density, especially for the mid-April planting. The exception for the mid-April planting date was `TAM Jalapeño1', which was not different at the two densities. If the increased income from higher yield can compensate for the cost of producing two seedlings in each transplant tray cell, then this technique should be employed when these types of peppers are used in early plantings.


2021 ◽  
Author(s):  
Ivica Djalovic ◽  
◽  
Vuk Radojevic ◽  
Vojislav Mihailovic ◽  
Sanja Vasiljevic ◽  
...  

Maize density is an important factor in cultivation which has significant effect on growth parameters. Newer hybrids have greater grain yield at higher plant densities than older hybrids. Differences in grain yield between older and newer maize hybrids were shown to be a function of plant population density. Optimum plant density for maximum grain yield per unit area may differ from hybrid to hybrid on account of significant interactions between hybrids and densities. Modern hybrids have shown tendencies to withstand higher levels of stress (i.e.- low N, high plant densities), which allow them to better sustain suitable photosynthetic rates, appropriate assimilate supplies, and maintain plant growth rates attributable to enhanced mineral nutrition and water use efficiency.


2002 ◽  
Vol 42 (2) ◽  
pp. 135 ◽  
Author(s):  
P. M. Evans ◽  
S. Walton ◽  
P. A. Riffkin ◽  
G. A. Kearney

The small-seeded annual clovers, balansa and Persian, are often assumed to be poor winter producers. Their small seed size, of about 1 mg or less, and poor regeneration, possibly due to inappropriate grazing management in many instances, contributes to this perception. To test the hypothesis that early growth of these clovers is determined by the weight of germinating seed, as it is in subterranean clover, an experiment with 2 cultivars of subterranean clover, Leura and Trikkala, 2 cultivars of balansa clover, Paradana and Bolta, and 1 of Persian clover, Nitro Plus, was established in the field at Hamilton, western Victoria, at 6 sowing densities. The winter production at 2 additional sites, Lake Bolac and Streatham, in their third and second and third seasons, respectively, was also examined. Plant density varied from 30 to 37000 plants/m2 across sites and species. With equal weight of germinating seed per unit area at sowing, balansa and Persian clovers produced more herbage in winter than did the 2 subterranean clover cultivars Leura and Trikkala (P<0.05). Even though there was high correlation between seed weight and seedling weight across all species shortly after emergence (r2 = 0.99), by harvest time no differences in plant weight existed between any treatments growing at the same plant density. From this we conclude the following: (i) for the same weight of germinable seed per unit area, balansa and Persian clovers produced more dry weight per hectare than subterranean clover, because they had higher plant densities; (ii) there were no differences in dry matter production per hectare between species growing at similar plant densities by harvest time at the end of winter; (iii) it appeared that in winter the small-seeded species exhibited a higher relative growth rate than the 2 subterranean clovers.


2009 ◽  
Vol 19 (3) ◽  
pp. 553-557 ◽  
Author(s):  
S. Alan Walters

Mini triploid (seedless) watermelons (Citrullus lanatus) are a growing segment of the U.S. watermelon market due to their small, one-serving size. Although mini triploid watermelons were first released and commercially grown about 6 years ago, little information is available for optimum planting densities that are needed to achieve the greatest percentage of marketable fruit in the 3- to 8-lb range. In 2006 and 2007, the fruit grade distribution response to six plant densities (2489, 3111, 4149, 6223, 8297, and 12,446 plants/acre) of four mini watermelon cultivars (Betsy, Petite Treat, Valdoria, and Vanessa) was measured at the Southern Illinois University Horticulture Research Center in Carbondale. ‘SP-1’ was used as the in-row pollenizer at 25% of the total planting. Although all cultivars responded similarly to the plant densities evaluated, ‘Vanessa’ provided the greatest fruit number and weight per acre, and percentage of fruit in the mini grade, compared with the other cultivars. Marketable mini triploid watermelon yield dramatically increased with closer in-row spacings. At lower plant densities (wider in-row spacings), a greater proportion of icebox-sized fruit (>8 lb) was produced, and the amount of marketable, mini-sized fruit (3–8 lb) declined. The grade distribution of mini triploid watermelon numbers and weights were the greatest at the highest plant density evaluated [0.5 ft in-row spacing (12,446 plants/acre)], with about 80% of the total yield in the mini grade. The greatest net revenues were also obtained at this high density. This study indicated that it is critical for producers of mini triploid watermelons to recognize the dramatic impact that plant density has on marketable fruit yield (3–8 lb). Growers of mini triploid watermelons will see a drastic improvement in revenues with closer in-row spacings compared with the approximate 2 ft in-row spacings currently used (about 4000 plants/acre). The increased cost of higher plant densities are more than offset by the greater return on investment.


1981 ◽  
Vol 97 (1) ◽  
pp. 55-68 ◽  
Author(s):  
Elizabeth A. Chapman

SUMMARYA study was made of the relationship between yields in particular size grades of carrots and onions and the number of plants per unit area with a view to providing adjustments to yields for differences in plant densities. It is concluded that the relationship for individual small grades cannot be fitted consistently by a single mathematical equation but that estimates of yields in small grades are best obtained by fitting a common equation to the accumulated yield at the limits of the grade and obtaining the yield by difference. Eleven previously published equations which have been shown to fit the relationship between total yield and plant density for a number of crops are compared with one newly developed for graded produce. It was found that the latter,where y = yield/ha, ρ = number of plants/m2 and A, B and C are constants, generally leads to the best fits when a large range of densities is present, but it is argued that, for adjustment of yields for small differences in densities such as are obtained in variety trials, a simpler equation such as a second degree polynomial is equally effective.


1978 ◽  
Vol 26 (4) ◽  
pp. 383-398 ◽  
Author(s):  
A. Darwinkel

The effect of plant density on the growth and productivity of the various ear-bearing stems of winter wheat was studied in detail to obtain information on the pattern of grain production of crops grown under field conditions. Strong compensation effects were measured: a 160-fold increase in plant density (5-800 plants/m2) finally resulted in a 3-fold increase in grain yield (282 to 850 g DM/m2). Max. grain yield was achieved at 100 plants/m2, which corresponded to 430 ears/m2 and to about 19 000 grains/m2. At higher plant densities more ears and more grains were produced, but grain yield remained constant. Tillering/plant was largely favoured by low plant densities because these allowed tiller formation to continue for a longer period and a greater proportion of tillers produced ears. However, at higher plant densities more tillers/unit area were formed and, despite a higher mortality, more ears were produced. The productivity of individual ears, from main stems as well as from tillers, decreased with increasing plant density and with later emergence of shoots. In the range from 5 to 800 plants/m2 grain yield/ear decreased from 2.40 to 1.14 g DM. At 800 plants/m2 nearly all ears originated from main stems, but with decreasing plant density tillers contributed increasingly to the number of ears. At 5 plants/m2, there were 23 ears/plant and grain yield/ear ranged from 4.20 (main stem) to 1.86 g DM (late-formed stems). Grain number/ear was reduced at higher densities and on younger stems, because there were fewer fertile spikelets and fewer grains in these spikelets. At the low density of 5 plants/m2, plants developed solitarily and grain yield/ear was determined by the number of grains/ear as well as by grain wt. Above 400 ears/m2, in this experiment reached at 100 plants/m2 and more, grain yield/ear depended solely on grain number, because the wt. of grains of the various stems were similar. The harvest index showed a max. of about 44% at a moderate plant density; at this density nearly max. grain yield was achieved. At low plant densities the harvest index decreased from 45% in main stems to about 36% in late-formed stems. However, no differences in harvest index existed between the various ear-bearing stems if the number of ears exceeded 400/m2. (Abstract retrieved from CAB Abstracts by CABI’s permission)


1988 ◽  
Vol 28 (5) ◽  
pp. 577 ◽  
Author(s):  
DG Cooksley ◽  
EA Goward

Leucaena (Leucaena leucocephala cv. Peru) was sown at 5 plant densities with 2 spatial arrangements at Brian Pastures Pasture Research Station, Gayndah, to determine the effects of these factors on leucaena and inter-row grass dry matter yield. During the 2 year establishment phase, yields of edible leucaena (leaves, pods, flowers and stems to a diameter of 5 mm) averaged 4400 and 2440 kg/ha respectively. Yields in subsequent years stabilised to an overall mean of 1360 kg/ha, with the amount of edible leucaena increasing with increasing leucaena plant density from 640 to 2260 kg/ha at 6000 and 62 500 leucaena plants/ha respectively. Edible leucaena yield for the mean of the 5 plant densities was increased by 38% when row spacing was doubled. Yields of both total and senesced leucaena were directly related to the annual rainfall. At the end of each growing season in May, edible leucaena yield remained stable between rainfall extremes of 492 and 878 mm while the amount of senesced leucaena litter increased. Edible leucaena yield was directly related to leucaena plant density (R2= 0.86). Annual total leucaena yield (edible leucaena yield plus leucaena litter) was best related to the plant parameters leucaena plant volume (R2 = 0.92), leucaena stem numbers (R2 = 0.90) and leucaena stem diameter (R2 = 0.90). Number of green panic (Panicum maximum var, trichoglume) shoots showed a marked increase at the 3 higher leucaena densities (mean of 28 shoots/m2) compared with the 2 lower leucaena densities (mean of 7 shoots/m2). Total soil nitrogen also increased at the 3 higher leucaena densities (mean of 0.186%) relative to the 2 lower leucaena densities (mean of 0.170%). Inter-row grass and grass litter yields both declined from 4640 and 4010 kg/ha to 31 10 and 2420 kg/ha respectively with increasing leucaena density. Maximum yields of edible leucaena were obtained when leucaena was grown at a density of 62 500 plants per ha in rows 0.8 m apart.


1998 ◽  
Vol 38 (2) ◽  
pp. 195
Author(s):  
T. Botwright ◽  
N. Mendham ◽  
B. Chung

Summary. The effect of plant density on growth, development, yield and quality of kabocha (buttercup squash) (Cucurbita maxima) was examined during 1992–93, at a field site in Cambridge, Tasmania. Plant densities ranged between 0.5 and 4.7 plants/m2. Marketable and total yields were fitted to a yield–density model. Total yield followed an asymptotic trend, approaching 33 t/ha at 4.7 plants/m2, while marketable yield had a parabolic relationship with density. Marketable yield increased to a maximum of 18 t/ha at 1.1 plants/m2, while declining at higher densities because of increased numbers of undersized fruit. Yield of vine marked and callused fruit did not vary with density, but represented a significant proportion of the total yield at all densities. High plant density reduced vegetative growth per plant due to competition for limited resources; as shown by decreased leaf area, number and length of vines, and plant dry weight. Yield tended to decline at high densities because of fewer female flowers and increased fruit abortion per plant. Plants at low densities had more vegetative growth but decreased yields, as increased abortion of fruit relative to the higher plant densities left only 1–2 large fruit per plant. Economic returns varied with plant density. At high densities, variable costs increased (particularly due to high seed cost) while gross income declined reflecting the relationship between marketable yield and plant density. The gross margin therefore declined at high densities.


1976 ◽  
Vol 66 (1) ◽  
pp. 113-123 ◽  
Author(s):  
S. Finch ◽  
G. Skinner

AbstractTo study the effects of plant density on populations of the cabbage root fly (Erioischia brassicae (Bch.) ) and the cabbage stem weevil (Ceutorhynchus quadridens (Panz.)), cauliflowers were planted in 24 concentric circles to achieve spacings of 10–90 cm at 22 plant densities (1·5–83/m2). Some plants were treated with a root drench of chlorfenvinphos. Each week female cabbage root flies laid approximately three times as many eggs per individual plant at the lowest than at the highest plant densities tested. This was equivalent to approximately 350 and 5000 eggs/m2, respectively. The numbers of cabbage root fly pupae produced ranged from 11/m2 at the lowest to 210/m2 at the highest plant density. In the absence of an insecticide, increasing the plant density considerably increased the absolute population of the pest without affecting cauliflower yield. Approximately seven times as many flies were produced per unit area of untreated mini-cauliflowers as from an equivalent area of plants growing at a conventional density. When chlorfenvinphos was not applied, damage by the cabbage stem weevil occurred in 30% and 70% of the plants grown at the lowest and highest densities, respectively.


1990 ◽  
Vol 70 (1) ◽  
pp. 127-137 ◽  
Author(s):  
M. J. MORRISON ◽  
P. B. E. McVETTY ◽  
R. SCARTH

To determine the effects of varying plant densities on summer rape (Brassica napus L.), the cultivar Westar was seeded in 15- and 30-cm row spacings at seeding rates of 1.5, 3.0, 6.0, and 12.0 kg ha−1. Plants seeded in 15-cm rows yielded more per area, produced more pods per plant and lodged less than those in 30-cm rows. Higher yields were associated with a more even plant distribution and a lower degree of intra-row competition. There were no significant protein, oil and chlorophyll concentration differences between the row spacing treatments. The highest yields (kg ha−1) were achieved with the 1.5 and 3.0 kg ha−1 seeding rates. Summer rape compensated for lower plant densities with the production of more branch racemes. As seeding rate increased, competitive mortality increased, resulting in greater etiolation at bolting, and greater lodging at harvest. Seed oil and protein concentrations were not affected by seeding rate. However, seed chlorophyll concentration decreased with increased seeding rate.Key words: Brassica napus, plant density, seed quality, rape (summer)


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