Author
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ROBERTS, BRUCE - Ohio Wesleyan University |
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LINDER, R - Ohio Wesleyan University |
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Krause, Charles |
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HARMANIS, RYAN - Ohio Wesleyan University |
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Submitted to: ARBORICULTURE AND URBAN FORESTRY
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 5/17/2011 Publication Date: 1/1/2012 Citation: Roberts, B.R., Linder, R.S., Krause, C.R., Harmanis, R. 2012. Humectants as post-plant soil amendments: effects on growth and physiological activity of drought-stressed, container-grown tree seedlings. Arboriculture and Urban Forestry. 38(1):6-12. Interpretive Summary: Two commercially-available organic soil amendments (humectants) were tested for their effectiveness in improving transplant establishment (growth and physiological activity) of drought-stressed, container-grown tree seedlings. While there was no effect of either humectant on foliar growth, fine root growth (roots less than 1mm diameter) was significantly greater for plants grown in the untreated substrate, a finding attributed to differences in the water holding characteristics of humectant-treated and untreated substrates. Measurements of physiological activity (e.g. net photosynthesis and plant-water relationships) for seedlings grown in humectant-treated substrate showed that there were significant differences between the two products tested, one of which had a positive effect on plant-water balance, and the other, which had a negative impact on the biophysical activity of membranes associated with photosystem II (PSII) photochemistry.
Technical Abstract: One-year-o1d, container-grown seedlings of red maple (Acer rubrum L.) and yellow-poplar (Liriodendron tulipirera L.) were treated with Hydretain ES~ (HydES) or Ecosentia1~ (ECOS) applied as a soil drench. A p~ogressive drought cycle was imposed after treatment and, as each seedling wilted, the leaves and roots were harvested. For both species, foliar growth was unaffected by HydES or EcoS, but root growth (surface area of roots |
