A model for light competition between vegetable crops and weeds

Röhrig, Manfred; Stützel, Hartmut

doi:10.1016/s1161-0301(00)00079-4

Cited by 19 publications

(11 citation statements)

References 29 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Weeds interfere in crop yield mainly competing for sunlight, water and soil nutrients; and the interference intensity for each one of these factors is difficult to be measured due to the inter relation among them, once the deficiency of one may affect the species competitiveness by the others (Fleck, 1992). Competition is the result of a relation between the distribution of plant limiting resources to the species in the agroecossystem, and the efficiency that each one has in using these resources to produce biomass (Rohrig & Stutzel, 2001).…”

Section: Introductionmentioning

confidence: 99%

Competition of Amaranthus species with dry bean plants

Carvalho

Christoffoleti²

2008

Sci. agric. (Piracicaba, Braz.)

View full text Add to dashboard Cite

Weeds compete with field crops mainly for water, light and nutrients, and this competition is among other factors, a function of the occurrence of weed density, and the intrinsic competitive ability of each vegetal species. The objective of this research was to evaluate the competitive ability of five weed species of the Amaranthus L. genus (A. deflexus, A. hybridus, A. retroflexus, A. spinosus and A. viridis) with dry bean plants (Phaseolus vulgaris L. - 'Carioca Precoce' cultivar), using the replacement series design. A fixed total density equivalent to 80 plants m-2 was used in pots of 2.8 L capacity varying the proportions between the species in coexistence. To install the experiment, Amaranthus seedlings were transplanted to the pots at the phenological stage of completely expanded cotyledon leaves, while the crop was seeded. A factorial scheme (5 x 5) was used to carry out the experiment, consisting of five species of Amaranthus (pigweeds) and five species proportions (beans:pigweeds): 4:0, 3:1, 2:2, 1:3 and 0:4. Randomized blocks with four replicates were installed and the experiment was repeated twice. Dry bean plants were more competitive than each one of the five Amaranthus species when the species proportion was equivalent. A. deflexus and A. viridis were the weed species which phenology were less affected by the competition with dry bean; the intraspecific competition was more damaging for dry bean plants, suggesting that the damages caused by the weeds are more related to high density of infestation than to the intrinsic competitive ability of the species.

show abstract

Section: Introductionmentioning

confidence: 99%

Competition of Amaranthus species with dry bean plants

Carvalho

Christoffoleti²

2008

Sci. agric. (Piracicaba, Braz.)

View full text Add to dashboard Cite

show abstract

“…Taken together, these results demonstrate that R/FR should be examined over the entire life cycle, as phenological stages may vary in response to R/FR. Furthermore, our results could be evidence of a survival mechanism that helps C. album overtop other species within a plant canopy environment (Röhrig & Stützel, 2001a,b) in order to project leaves into areas of open daylight (Ballaré et al. , 1997).…”

Section: Resultsmentioning

confidence: 87%

“…Chenopodium album (L.) can be used as a model invasive weed because this ruderal is a widely distributed (Williams, 1963; Grime, 1974; Holm et al. , 1977), shade‐avoiding species that adapts its morphology to shade its competitors (Röhrig & Stützel, 2001a,b). Phytochrome researchers used C. album to understand physiological changes caused by R/FR (Holmes & Smith, 1977; Morgan & Smith, 1978, 1981; Child et al.…”

Section: Introductionmentioning

confidence: 99%

ExploringChenopodium albumadaptive traits in response to light and temperature stresses

Mahoney

Swanton

2008

Weed Research

View full text Add to dashboard Cite

Summary Weeds within canopies are depleted in photosynthetic photon flux density (PPFD) and red to far‐red light ratio (R/FR) throughout their lifespan. Growth cabinet studies isolated PPFD and R/FR effects and explored the adaptive traits of a model invasive weed, Chenopodium album, to light and temperature. Reproductive development progressed rapidly at high temperature, yet the rate of leaf appearance was insensitive to temperatures of 25:15 and 10:5°C (day:night). Low R/FR effects were detected early in the life cycle, but by seed set, growth was influenced by low PPFD. C. album adapted to the simulated canopy environments by delaying seed set, growing taller and producing more leaf area per mol of accumulated incident PPFD. Low PPFD reduced seed number per plant and the carbon/nitrogen ratio of those seeds, but not seed weight. PPFD was a primary cue for many shade avoidance traits and only under low PPFD did R/FR modify the expression of these traits. This study elucidates the adaptive strategies that make C. album a persistent weed.

show abstract

“…It is important to distinguish between the effects an individual plant has on resources and how that plant responds to the preemption of resources by its neighbors (Goldberg, 1990). Thus, the intensity of competition is determined by two processes: (1) the effects of neighbors on resource availability and (2) the ability of individuals to tolerate or compensate for these effects through plasticity and other "behavioral" responses (Hrig and Tzel, 2001). Neighborhood effects have often been evaluated from regressions of individual plant performance, such as size or growth, on neighborhood indices, which represent the condition of the neighborhood based on distance, size, species and or spatial arrangement of neighbors (Mead, 1996).…”

Section: Introductionmentioning

confidence: 99%

Frequency, Damage and Comparative Phonology of Annual Ground Cherry (Physalis divaricata L.) Weed in Sugar Beet Fields

Alam¹,

Alizade²,

Mashhadi³

2011

Not Sci Biol

View full text Add to dashboard Cite

Ground cherry (Physalis divaricata L.) is one of the most important summer weeds in sugar beet crop in the west of Iran. In order to estimate the damage rate of this weed, field studies were conducted to quantify the effect of ground cherry density on sugar beet yield and to determine relationships among different weed densities (0, 0.5, 1, 2, 4, 8 and 16 plants m -2 ) and sugar beet yield in 2008. The experiments were arranged in a randomized complete block design (RCBD) with four replications. In addition, the neighborhood effect of ground cherry was assessed in a completely randomized design. Neighborhood effect was surveyed from zero to 125 cm apart from each sugar beet plant to ground cherry. Density of ground cherry was estimated as the systematic method in 30 sugar beet fields that were chosen randomly.Phonology of ground cherry was recorded based on the GDD (Growth Degree Day) and date. Results showed that two weed plants m 2 of this weed resulted in 34% damage to sugar beet. Ground cherry significantly reduced yield of sugar beet when sown 50 cm apart from crop plant. Crop damage of sugar beet was 41% when ground cherry seeds were sown at zero cm apart from each sugar beet plant. Flowering of ground cherry occurred in the middle of June when it received 61.45-75 GDD and it proved that ground cherry is a neutralized weed to the long day.

show abstract

A model for light competition between vegetable crops and weeds

Cited by 19 publications

References 29 publications

Competition of Amaranthus species with dry bean plants

Competition of Amaranthus species with dry bean plants

ExploringChenopodium albumadaptive traits in response to light and temperature stresses

Frequency, Damage and Comparative Phonology of Annual Ground Cherry (Physalis divaricata L.) Weed in Sugar Beet Fields

Contact Info

Product

Resources

About