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The Role of Light in the Emergence of Weeds: Using Camelina microcarpa as an Example.

Royo-Esnal A, Gesch RW, Forcella F, Torra J, Recasens J, Necajeva J - PLoS ONE (2015)

Bottom Line: Optimum temperature is necessary for metabolic processes that generate energy for growth, while turgor pressure is necessary for root and shoot elongation which eventually leads to seedling emergence from the soil.Most emergence models do not usually consider light as a residual factor, but it could have an important role as it can alter directly or indirectly the dormancy and germination of seeds.HTT based on hourly estimates is also compared with that based on daily estimates.

View Article: PubMed Central - PubMed

Affiliation: Dpt. D'Hortofruticultura, Botànica i Jardineria, Agrotecnio, Universitat de Lleida. Alcalde Rovira Roure 191, 25198, Lleida, Spain.

ABSTRACT
When modelling the emergence of weeds, two main factors are considered that condition this process: temperature and soil moisture. Optimum temperature is necessary for metabolic processes that generate energy for growth, while turgor pressure is necessary for root and shoot elongation which eventually leads to seedling emergence from the soil. Most emergence models do not usually consider light as a residual factor, but it could have an important role as it can alter directly or indirectly the dormancy and germination of seeds. In this paper, inclusion of light as an additional factor to photoperiod and radiation in emergence models is explored and compared with the classical hydrothermal time (HTT) model using Camelina microcarpa as an example. HTT based on hourly estimates is also compared with that based on daily estimates. Results suggest that, although HTT based models are accurate enough for local applications, the precision of these models is improved when HTT is estimated hourly and solar radiation is included as a factor.

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Distribution of the percentages of emergence of Table 1 throughout the two growing seasons, 2011–12 and 2012–13.(Grey line) Almenar. (Black line) Morris. Dates in the x-axis are in month/day/year.
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pone.0146079.g001: Distribution of the percentages of emergence of Table 1 throughout the two growing seasons, 2011–12 and 2012–13.(Grey line) Almenar. (Black line) Morris. Dates in the x-axis are in month/day/year.

Mentions: In addition to differences in total emergence distributed throughout the seasons, emergence was delayed in Morris during autumn 2012 compared to Almenar (Fig 1). This delay was caused by the drought conditions in Morris in autumn 2012 (Table 1).


The Role of Light in the Emergence of Weeds: Using Camelina microcarpa as an Example.

Royo-Esnal A, Gesch RW, Forcella F, Torra J, Recasens J, Necajeva J - PLoS ONE (2015)

Distribution of the percentages of emergence of Table 1 throughout the two growing seasons, 2011–12 and 2012–13.(Grey line) Almenar. (Black line) Morris. Dates in the x-axis are in month/day/year.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4696734&req=5

pone.0146079.g001: Distribution of the percentages of emergence of Table 1 throughout the two growing seasons, 2011–12 and 2012–13.(Grey line) Almenar. (Black line) Morris. Dates in the x-axis are in month/day/year.
Mentions: In addition to differences in total emergence distributed throughout the seasons, emergence was delayed in Morris during autumn 2012 compared to Almenar (Fig 1). This delay was caused by the drought conditions in Morris in autumn 2012 (Table 1).

Bottom Line: Optimum temperature is necessary for metabolic processes that generate energy for growth, while turgor pressure is necessary for root and shoot elongation which eventually leads to seedling emergence from the soil.Most emergence models do not usually consider light as a residual factor, but it could have an important role as it can alter directly or indirectly the dormancy and germination of seeds.HTT based on hourly estimates is also compared with that based on daily estimates.

View Article: PubMed Central - PubMed

Affiliation: Dpt. D'Hortofruticultura, Botànica i Jardineria, Agrotecnio, Universitat de Lleida. Alcalde Rovira Roure 191, 25198, Lleida, Spain.

ABSTRACT
When modelling the emergence of weeds, two main factors are considered that condition this process: temperature and soil moisture. Optimum temperature is necessary for metabolic processes that generate energy for growth, while turgor pressure is necessary for root and shoot elongation which eventually leads to seedling emergence from the soil. Most emergence models do not usually consider light as a residual factor, but it could have an important role as it can alter directly or indirectly the dormancy and germination of seeds. In this paper, inclusion of light as an additional factor to photoperiod and radiation in emergence models is explored and compared with the classical hydrothermal time (HTT) model using Camelina microcarpa as an example. HTT based on hourly estimates is also compared with that based on daily estimates. Results suggest that, although HTT based models are accurate enough for local applications, the precision of these models is improved when HTT is estimated hourly and solar radiation is included as a factor.

Show MeSH
Related in: MedlinePlus