Ecological relationships of wild rice, Zizania spp. 10. Effects of sediment and among-population variations on plant density in Zizania palustris

2002 ◽  
Vol 80 (12) ◽  
pp. 1283-1294 ◽  
Author(s):  
P F Lee
Keyword(s):  
Seed Production ◽  
Wild Rice ◽  
Plant Density ◽  
Reproductive Potential ◽  
Resource Depletion ◽  
Dry Weight ◽  
Asymmetric Competition ◽  
Zizania Palustris ◽  
Nutrient Levels ◽  
Plant Densities

The influence of nutrients and intraspecific variations in growth form were examined for their effect on plant density in stands of northern wild rice, Zizania palustris L. In a field situation, densities of a size-restricted wild rice population increased as nutrient levels in the sediment increased. No self-thinning occurred until the population density exceeded 350 plants/m2. A series of controlled experiments examined whether these wild rice densities were determined by resource depletion and (or) intraspecific competition. As nutrient levels increased under constant plant densities, tillering, dry weight, and seed production increased more for populations with the capacity for higher vegetative and reproductive potential. As plant densities increased under constant nutrient levels, height, weight, and seed production declined but inequality of individual plants increased. When both nutrient levels and population densities were increased simultaneously, seed production per panicle declined at higher densities under unfertilized conditions but was unaffected in the treatment with the highest fertilizer level. It was hypothesized that plant densities under field conditions were the result of an integrated mechanism that was influenced by nutrients and the degree of asymmetric competition characteristic of the population. As nutrient levels increase, plant densities would be expected to decrease for populations with high levels of asymmetric competition and increase for populations with low levels of asymmetric competition.Key words: wild rice, density effects, nutrients, intraspecific variation.

Effects of Giant Burreed (Sparganium eurycarpum) and Shade on Wild Rice (Zizania palustris)

Weed Science ◽  
1987 ◽  
Vol 35 (5) ◽  
pp. 640-646 ◽  
Author(s):  
Sharon A. Clay ◽  
Ervin A. Oelke
Keyword(s):  
Wild Rice ◽  
Dry Weight ◽  
Fertilizer Application ◽  
Shoot Density ◽  
Growth And Yield ◽  
Zizania Palustris ◽  
Major Mechanism ◽  
Panicle Number ◽  
In The Wild ◽  
Sparganium Eurycarpum

Studies were conducted at Grand Rapids, MN, to determine the effect of giant burreed (Sparganium eurycarpumEngelm. # SPGEU) planted at 6, 12, and 24 corms/m2on wild rice (Zizania palustrisL. ‘K2′) growth and yield. Giant burreed, a spreading perennial, had shoot densities of 21, 29, and 42/m2at harvest for the 6, 12, and 24 corms/m2treatments, respectively. Wild rice yield and panicle number were reduced approximately 60% when giant burreed shoot density was 40/m2or higher when compared to the weed-free control. Giant burreed did not interfere with nutrient uptake of wild rice on a whole-plant basis, and increased N fertilizer application did not reduce losses in dry weight. Giant burreed reduced penetration of photosynthetically active radiation (PAR) from 2 to 35% in the wild rice canopy from the early tillering to the anthesis stage of wild rice development. In growth chamber studies, wild rice dry weight and panicle number were reduced by 46 and 65%, respectively, when wild rice was shaded for 12 weeks and compared to a full light treatment. Reduction of PAR penetration into the wild rice canopy appears to be the major mechanism of giant burreed interference with wild rice.

Chemical Control of Giant Burreed (Sparganium eurycarpum) in Wild Rice (Zizania palustris)

1990 ◽  
Vol 4 (2) ◽  
pp. 294-298
Author(s):  
Sharon A. Clay ◽  
Ervin A. Oelke
Keyword(s):  
Chemical Control ◽  
Wild Rice ◽  
Dry Weight ◽  
Amine Salt ◽  
Leaf Stage ◽  
Zizania Palustris ◽  
Sparganium Eurycarpum

The response of giant burreed to bentazon, propanil, 2,4-D (amine salt), and 2,4-D plus crop oil (0.5% v/v) was evaluated at the 2-aerial-leaf stage of wild rice. Bentazon, 2,4-D, and 2,4-D plus crop oil at 1.1 kg/ha or more in 1984, and propanil and 2,4-D plus crop oil at 4.5 kg/ha in 1985 reduced giant burreed dry weight. Generally, herbicide rates above 1.1 kg/ha injured wild rice and reduced yields compared to weed-free controls. None of the study treatments resulted in effective giant burreed control without unacceptable injury to wild rice.

Cultural Control of Common Waterplantain (Alisma triviale) in Wild Rice (Zizania palustris)

Weed Science ◽  
1983 ◽  
Vol 31 (4) ◽  
pp. 562-566 ◽  
Author(s):  
Joel K. Ransom ◽  
Ervin A. Oelke
Keyword(s):  
Seed Yield ◽  
Wild Rice ◽  
Rice Yield ◽  
Dry Weight ◽  
Cultural Control ◽  
Burial Depth ◽  
Rice Seed ◽  
Zizania Palustris ◽  
Grand Rapids ◽  
Water Depths

Experiments were conducted to determine the influence of water depth, fall flooding, and burial depth on the development of common waterplantain (Alisma trivialePursh. # ALSPA) in wild rice (Zizania palustrisL.). The optimum water depths for common waterplantain from corms were 20 cm when grown outside in submerged pots at St. Paul and 2 and 15 cm when grown in a sloping field at Grand Rapids. Growth of common waterplantain from seeds was maximum at the lowest water depths (2 to 7 cm) at both locations. Wild rice dry weight and seed yield in the same experiments were maximum at the 20- and 30-cm water depths at St. Paul and the 15- and 28-cm depths at Grand Rapids. The increased wild rice seed yield and dry weight at these depths was related to increased tiller production. Wild rice yield was similar at all water depths at Grand Rapids when grown with common waterplantain from corms at a density of 11 plants/m2. Water depths that decreased the effect of common waterplantain interference with wild rice, reduced wild rice yield. Establishment of common waterplantain from corms was maximum at the 5- and 15-cm depths and was severely reduced at the 0- and 30-cm soil depths in soils not flooded in the fall but flooded in the spring. Fall flooding killed all corms regardless of burial depth. Corm mortality under fall-flooded conditions may be due to the effects of ice-encasement.

scholarly journals Four Cultivars of Japanese Barberry Demonstrate Differential Reproductive Potential under Landscape Conditions

HortScience ◽  
2006 ◽  
Vol 41 (3) ◽  
pp. 762-767 ◽  
Author(s):  
Jonathan M. Lehrer ◽  
Mark H. Brand ◽  
Jessica D. Lubell
Keyword(s):  
Seed Production ◽  
Invasive Plant ◽  
Germination Rate ◽  
Reproductive Potential ◽  
Dry Weight ◽  
Seedling Vigor ◽  
Berberis Thunbergii ◽  
Invasive Potential ◽  
Japanese Barberry ◽  
Landscape Plants

While japanese barberry (Berberis thunbergii DC.) is an acknowledged invasive plant naturalized throughout the eastern and northern U.S., the danger posed by its popular horticultural forms is unknown and controversial. This work analyzed the reproductive potential and seedling growth of four ornamental genotypes important to the nursery industry. Fruit and seed production was quantified in 2001, 2002, and 2003 for multiple landscape plants of B.t. var. atropurpurea, `Aurea', `Crimson Pygmy', and `Rose Glow'. The average number of seeds produced per landscape specimen ranged from lows of 75 and 90 for `Aurea' and `Crimson Pygmy' to 2968 for var. atropurpurea and 762 for `Rose Glow'. Seed production relative to canopy surface area for `Rose Glow' was similar to `Aurea' and `Crimson Pygmy' and all three cultivars were less prolific than var. atropurpurea in this regard. Cleaned and stratified seeds from var. atropurpurea, `Crimson Pygmy' and `Rose Glow' showed an average greenhouse germination rate of 70% to 75%, while `Aurea' yielded 46% germination. A subpopulation of seedlings from each genotype accession was grown further outdoors in containers for a full season to ascertain seedling vigor and development. The vigor of 1-year-old seedlings, as measured by dry weight of canopy growth, for progeny derived from `Aurea' (0.70 g) and `Crimson Pygmy' (0.93 g) was significantly less than var. atropurpurea (1.20 g) and `Rose Glow' (1.33 g). These results demonstrate that popular japanese barberry cultivars express disparate reproductive potential that, after further study, may be correlated with invasive potential. Some popular commercial cultivars may pose significantly less ecological risk than others.

scholarly journals Non-Structural Carbohydrate Metabolism, Growth, and Productivity of Maize by Increasing Plant Density

Agronomy ◽  
2018 ◽  
Vol 8 (11) ◽  
pp. 243 ◽  
Author(s):  
Jairo Cazetta ◽  
Marcos Revoredo
Keyword(s):  
Sucrose Synthase ◽  
Plant Density ◽  
Specific Activity ◽  
Sucrose Concentration ◽  
Soluble Sugars ◽  
Dry Weight ◽  
Plant Production ◽  
Crop Density ◽  
Plant Densities ◽  
Narrow Row

Increasing plant density seems to improve the productivity of maize crops, and the understanding of how the metabolism of non-structural carbohydrates is affected in plants under high crop density is critical. Thus, with the objective of further clarifying this issue, maize plants were subjected to densities from 30,000 to 90,000 plants ha−1, and the plant growth, soluble sugars and starch contents, invertase and sucrose synthase activities, and plant production were evaluated. We found that the stalk is more sensitive to the increasing plant density than leaves and kernels. The dry weight of the stalk and leaves per single plant decreased more drastically from low to intermediate plant densities, while grain production was reduced linearly in all plant density ranges, leading to higher values of harvest index in intermediate plant densities. The sucrose concentration did not change in leaves, stalk, or kernels of plants subjected to increasing plant densities at the R4 stage. Also, the specific activity of soluble invertase, bound invertase, and sucrose synthase did not change in leaf, stalk, or kernels of plants subjected to increased plant density. The productivity was increased with the increase in plant density, using narrow row (0.45 m) spacing.

Effect of barley plant density on wild oat interference, shoot biomass and seed yield under zero tillage

1999 ◽  
Vol 79 (4) ◽  
pp. 655-662 ◽  
Author(s):  
J. T. O'Donovan ◽  
J. C. Newman ◽  
K. N. Harker ◽  
R. E. Blackshaw ◽  
D. W. McAndrew
Keyword(s):  
Seed Yield ◽  
Yield Loss ◽  
Plant Density ◽  
Interactive Effect ◽  
Dry Weight ◽  
Barley Plant ◽  
Wild Oat ◽  
Zero Tillage ◽  
Shoot Dry Weight ◽  
Plant Densities

There has been little research aimed at developing regression models to describe the effects of barley and wild oat plant density on barley yield loss, or wild oat biomass and seed yield. Such models are an important component of integrated weed management systems, and can help determine when weed control with herbicides is economical. Field experiments were conducted over 4 yr at Vegreville, Alberta, to determine the interactive effects of wild oat and barley plant density on barley and wild oat variables in a zero tillage system. A nonlinear regression model in most cases provided good descriptions of barley yield loss, wild oat shoot dry weight, and wild oat seed yield as functions of wild oat and barley plant densities. The interactive effect of wild oat and barley plant density on percentage barley yield loss did not differ significantly (P = 0.05) among years. A pooled regression model describing barley yield loss accounted for 57% of the variation, and provides a means of estimating yield loss due to wild oat in barley grown under zero tillage. Barley yield loss increased as wild oat density increased but the magnitude of the yield loss diminished with increasing barley plant density. Wild oat economic threshold densities varied among years, and were strongly influenced by barley price and expected wild oat-free yield. Economic thresholds were greater at higher barley plant densities. Barley seed weight decreased with increasing barley plant density, and to a lesser extent with increasing wild oat density. The interactive effect of wild oat and barley plant density on wild oat seed yield varied significantly with year, and appeared to be influenced by climatic conditions. The cooler, wetter spring of 1996 favored wild oat seed production (by several orders of magnitude) compared with the relatively warmer and drier spring of 1995. Each year wild oat seed yield and shoot dry weight decreased as barley plant density increased. The results suggest that seeding barley at relatively high rates may reduce the need for wild oat control with herbicides in zero tillage systems. Key words: Zero tillage, wild oat interference, barley seeding rate, nonlinear regression

scholarly journals Plant density in production of mini lettuce cultivars in organic system management

2014 ◽  
Vol 32 (3) ◽  
pp. 342-347 ◽  
Author(s):  
Keiko Takahashi ◽  
Antonio II Cardoso
Keyword(s):  
Plant Density ◽  
Block Design ◽  
Dry Weight ◽  
Good Alternative ◽  
Fresh Weight ◽  
Marketable Yield ◽  
Higher Plant ◽  
Organic System ◽  
Randomized Block Design ◽  
Plant Densities

Production of mini vegetables in organic system is a good alternative to improve profit, but there are no researches about the optimum plant density for these cultivars in Brazilian conditions. Two experiments were conducted to evaluate the production of mini lettuce cultivars in different plant densities. Experiment 1 was conducted from January 1th (sowing) to February 10th(harvesting), 2012. The experimental design was completely randomized blocks, with six treatments in factorial scheme, 3 mini lettuce cultivars (Tudela, Renoir and Sartre) x 2 spacing between plants (16 and 20 cm), with eight replications and plots (2.04 m2) with six rows, spaced 15 cm. Experiment 2 was conducted from June 6th (sowing) to July 18th (harvesting), 2012. The cultivars Sartre and Renoir were evaluated under four plant densities (444,444; 333,333; 266,667 and 200,000 plants ha-1, corresponding to spacing of 15x15, 15x20, 25x15 and 25x20 cm, respectively). Eight treatments were defined by a factorial scheme 2 (cultivars) x 4 (plant densities) and arranged in a completely randomized block design, with nine replications and plots with 2.04 m2. The evaluated characteristics in both experiments were total and marketable fresh weight per plant, plant dry weight, plant diameter and height, marketable yield and discard percentage. In first experiment, during the summer, cultivar Sartre showed the highest marketable fresh weight (72 g plant-1). Heaviest plants (91.6 g plant-1) were obtained with the higher plant spacing, but the highest yield (2.51 kg m-2) was obtained with the smaller spacing. In winter, plants with higher total (190 g plant-1) and marketable (146 g planta-1) fresh weight were obtained with cultivar Sartre, and the same was observed in low plant density. However, the higher plant density, the higher the yield.

Effects of atmospheric fluorides on foliage, flower, fruit, and seed production in wild raspberry and blueberry

1984 ◽  
Vol 62 (12) ◽  
pp. 2827-2834 ◽  
Author(s):  
R. J. Staniforth ◽  
S. S. Sidhu
Keyword(s):  
Seed Production ◽  
Germination Rate ◽  
Reproductive Potential ◽  
Dry Weight ◽  
Control Site ◽  
Polluted Site ◽  
Leaf Fall ◽  
Foliar Injury ◽  
Size Number ◽  
Vegetative Spread

Reproductive and vegetative characteristics of raspberry and blueberry plants were monitored at six sites downwind from a phosphorus plant which emitted gaseous and particulate fluorides. Atmospheric fluoridation rates ranged from an average of 347.4 μg F∙dm−2∙week−1 (or 11.38 μg F∙m−1) at 1.4 km to 2.5 μg F∙dm−2∙week−1 (or 0.08 μg F∙m−3) at 18.7 km from the source. The highest fluoridation levels were in July, the month in which flowering in the two species reached its peak. At the most polluted site, flower mortality was 89% for blueberry and 78% for raspberry; this accounted for most of the loss in reproductive potential. Comparative values of the control site (18.7 km from source) were 27 and 26%, respectively. There were 21- and 10-fold decreases in seed production per plant in blueberry and raspberry, respectively, as well as significant decreases in the size, number, and dry weight of fruit. Fluoride damage to blueberry plants did not result in any effects being passed on to seedlings, except for a slightly accelerated germination rate. Fluoride accumulations in the foliage of plants 1.4 km from the source were 403 ppm for raspberry and 216 ppm for blueberry but only 8 and 9 ppm, respectively, at the control site. Fluoride-affected raspberry plants also showed foliar injury, enhanced vegetative spread, and delayed leaf fall in the autumn.

Growth and Development of Wild-Proso Millet (Panicum miliaceum) Biotypes

1990 ◽  
Vol 4 (2) ◽  
pp. 415-419 ◽  
Author(s):  
Charlotte V. Eberlein ◽  
Edith L. Lurvey ◽  
Timothy L. Miller ◽  
Janis L. Michael
Keyword(s):  
Leaf Area ◽  
Seed Production ◽  
Seed Dormancy ◽  
Growth And Development ◽  
Seed Weight ◽  
Reproductive Potential ◽  
Dry Weight ◽  
Field Studies ◽  
Panicum Miliaceum ◽  
Proso Millet

Growth and development of three wild-proso millet biotypes (Cambridge, LeSueur, and Morris) and one cultivated proso millet (‘Crown’) were compared under noncompetitive conditions in field studies. LeSueur and Cambridge were taller than Crown and Morris at maturity. All wild types had greater leaf area and dry weight at maturity than Crown. Crown headed earlier than the wild types, and among the wild types, Cambridge was slowest to mature. Seed production was 1.4 to 2 times greater for wild than cultivated proso millet, and averaged 48 000, 69 000, 83 000, and 94 000 seeds/plant for Crown, Cambridge, LeSueur, and Morris, respectively. Mean seed weight was 4.0 and 3.8 mg/seed for LeSueur and Morris, respectively, and 5.8 and 5.9 mg/seed for Crown and Cambridge, respectively. LeSueur and Morris seed shattered readily, but Cambridge seed shattered relatively little. Seed dormancy was greater in LeSueur and Morris than in Cambridge. Based on reproductive potential, shattering, and dormancy characteristics, LeSueur and Morris appeared to have more weedy characteristics than Cambridge.

scholarly journals Pericarp growth dynamics associate with final grain weight in wheat under contrasting plant densities and increased night temperature

2020 ◽  
Vol 126 (6) ◽  
pp. 1063-1076 ◽  
Author(s):  
Jaime Herrera ◽  
Daniel F Calderini
Keyword(s):  
Water Content ◽  
Dry Matter ◽  
Plant Density ◽  
Growth Dynamics ◽  
Dry Weight ◽  
Grain Filling ◽  
Kernel Weight ◽  
Grain Weight ◽  
Density Control ◽  
Plant Densities

Abstract Background and Aims The pericarp weight comprises <17 % of wheat grain weight at harvest. The pericarp supports the hydration and nutrition of both the embryo and endosperm during early grain filling. However, studies of the pericarp and its association with final grain weight have been scarce. This research studied the growth dynamics of wheat pericarp from anthesis onwards and its relationship to final grain weight under contrasting plant densities and night warming. Methods Two spring wheat cultivars contrasting in kernel weight (Bacanora and Kambara) were sown in field conditions during seasons 2012–13 and 2014–15. Both genotypes were grown under contrasting plant density (control, 370 plants m–2; and low plant density, 44 plants m–2) and night temperatures, i.e. at ambient and increased (>6 °C) temperature for short periods before and after anthesis. From anthesis onward, grains were harvested every 3 or 4 d. Grain samples were measured and the pericarp was removed with a scalpel. Whole grain and pericarp fresh and dry weight were weighed with a precision balance. At harvest, 20 grains from ten spikes were weighed and grain dimensions were measured. Key Results Fresh weight, dry matter and water content of pericarp dynamics showed a maximum between 110 and 235 °Cd. Maximum dry matter of the pericarp ranged between 4.3 and 5.7 mg, while water content achieved values of up to 12.5 mg. Maximum values and their timings were affected by the genotype, environmental condition and grain position. Final grain weight was closely associated with maximum dry matter and water content of the pericarp. Conclusions Maximum pericarp weight is a determinant of grain weight and size in wheat, which is earlier than other traits considered as key determinants of grain weight during grain filling. Better growing conditions increased maximum pericarp weight, while higher temperature negatively affected this trait.

Sign in / Sign up

Export Citation Format

Share Document