Simulation of Moisture Stress Effects on Soybean Yield Components in Nebraska

Studies addressing the interaction of different spatial arrangement in soybean are needed in order to achieve management that leads to higher grain yield associated with rational seed use. The objective of this work was to evaluate the yield components and productivity of an undetermined growth type soybean as a function of different row spacing and plant densities. The treatments consisted of three row spaces (0.25, 0.35 and 0.45 m) and three plant population densities (30, 40 and 50 plants/m²). There was no interaction of row spaces and plant population on soybean yield. Regarding the overall spacing average, the grain yield of the population of 30/m² plants was higher than the productivity of the populations of 40 and 50/m² plants. The largest populations reduce plant sizes due to greater competition between plants. In addition, smaller populations promote higher individual plant yields due to the increase components of the production. This characteristic is defined as the ability of the plant to change its morphology and yield components in order to adapt to the conditions imposed by the spatial arrangement.

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Influence of Planting Dates and Plant Population on Soybean Yield and Yield Components under Peshawar Conditions

Pakistan Journal of Biological Sciences ◽

10.3923/pjbs.2000.1892.1896 ◽

2000 ◽

Vol 3 (11) ◽

pp. 1892-1896

Author(s):

Amir Zaman Kha . ◽

M. Akhtar . ◽

M. Riaz . ◽

N. Ahmad . ◽

P. Shah .

Keyword(s):

Yield Components ◽

Plant Population ◽

Planting Dates ◽

Soybean Yield ◽

Yield And Yield Components

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Interference of GR® Volunteer Corn Population and Origin on Soybean Grain Yield Losses

Planta Daninha ◽

10.1590/s0100-83582018360100003 ◽

2018 ◽

Vol 36 (0) ◽

Cited By ~ 2

Author(s):

C. PIASECKI ◽

M.A. RIZZARDI ◽

D.P. SCHWADE ◽

M. TRES ◽

J. SARTORI

Keyword(s):

Grain Yield ◽

Yield Components ◽

Individual Plant ◽

Soybean Yield ◽

Maximum Loss ◽

Tillage System ◽

Volunteer Corn ◽

Corn Plants ◽

F2 Generation ◽

The Impact

ABSTRACT: The cultivation of GR® maize prior to soybean, mainly in the no-tillage system favors the higher occurrence of GR® volunteer corn interfering in soybean crops. Volunteer corn originate from seeds that were lost during harvest or from non-harvested seeds from the field; these are individual seeds, originating individual plants, or several seeds adhered to segments of the rachis, which originate clumps. Volunteer corn in the form of clumps predominates in soybean crops, but little information about its effect on soybean is available in the literature. During two years, three experiments were carried out with the objective of evaluate the impact of the interference of GR® F2 generation volunteer corn populations coming from individual and clump seeds (seven corn plants emerged at the same point) over soybean yield components and grain yield. The results show that losses in soybean yield components and grain yield are influenced by the population and origin of volunteer corn. Clumps cause losses over 90% for populations above four clumps m-2, while the mean maximum loss observed for individual plants was 83% in the largest studied populations. Soybean yield decreased significantly when competing with populations below one plant or clump m-2, being 16% and 46% in the population of 0.5 individual plant and clump m-2, respectively.

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Light reduction and moisture stress: effects on growth and water relations of western larch seedlings

Canadian Journal of Forest Research ◽

10.1139/x85-013 ◽

1985 ◽

Vol 15 (1) ◽

pp. 72-77 ◽

Cited By ~ 8

Author(s):

Nan C. Vance ◽

Steven W. Running

Keyword(s):

Stomatal Closure ◽

Biomass Accumulation ◽

Dry Weight ◽

Moisture Stress ◽

Western Larch ◽

Light Reduction ◽

Stress Effects ◽

Reduced Height ◽

Terminal Bud ◽

Nighttime Temperatures

Ten-week-old western larch (Larixoccidentalis Nutt.) seedlings were grown in a greenhouse under 70, 37, and 27% full sunlight from late July to early October. In August, seedlings under each light treatment were repetitively water stressed until predawn leaf water potential (Bψ1) reached one of three levels: no stress (> −0.4 MPa), moderate stress (−0.7 to −1.0 MPa), and severe stress (−1.5 to −1.8 MPa). Moisture stressing significantly reduced height and diameter of seedlings grown under 70% light. Light reduction reduced shoot and root biomass accumulation. A positive linear relation was found between root dry weight and light intensity. The largest seedlings (on a weight basis) received the highest light, were unstressed, and had the lowest shoot/root ratios. Terminal bud set was not affected by light reduction or moisture stressing but occurred under a 14-h photoperiod and reduced nighttime temperatures. Stressed and shaded seedlings had significantly reduced diurnal K1 and stress-cycled seedlings showed an adjustment to stressing. The K1 of unstressed seedlings was correlated with humidity deficit (ABHD), and K1 of stressed seedlings, with Bψ1, and ABHD. Maximum K1 declined with decreasing Bψ1, but not to a level indicating complete stomatal closure.

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Correlations of soybean yield with soil porosity and bulk density of an Oxisol

Pesquisa Agropecuária Tropical ◽

10.1590/1983-40632018v4852654 ◽

2018 ◽

Vol 48 (4) ◽

pp. 476-485

Author(s):

Sérgio Ricardo Lima Negro ◽

Diego dos Santos Pereira ◽

Rafael Montanari ◽

Flávio Carlos Dalchiavon ◽

Christtiane Fernandes Oliveira

Keyword(s):

Spatial Variability ◽

Grain Yield ◽

Bulk Density ◽

Yield Components ◽

Particle Density ◽

Soil Porosity ◽

No Tillage ◽

Soybean Yield ◽

Volumetric Flask ◽

Soil Attributes

ABSTRACT The spatial variability of soil physical attributes is important to indicate management practices that best suit agricultural areas. This study aimed to analyze spatial correlations between soybean grain yield and soil mass-volume relationships, in order to select which attribute is correlated with yield, as well as to evaluate the spatial variability of soil attributes and yield components of this crop, in an Oxisol under no-tillage system. The soil attributes analyzed (0.0-0.10 m and 0.10-0.20 m) were the following ones: soil bulk density (paraffin-coated clod and volumetric ring methods), particle density (volumetric flask and modified volumetric flask methods) and total porosity. The soybean yield components were evaluated as it follows: grain yield, number of pods per plant, number of grains per pod, mass of 100 grains, grain mass per plant, plant population and plant height. The total soil porosity, calculated by the relations between the bulk density (volumetric ring method) and particle density (volumetric flask), in the 0.10-0.20 m layer, was the best indicator of soybean grain yield under no-tillage conditions.

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