Sulfometuron methyl influences seedling growth and leaf function of three conifer species |
| |
Authors: | Nathan D Robertson Anthony S Davis |
| |
Institution: | (1) Center for Forest Nursery and Seedling Research, College of Natural Resources, University of Idaho, PO Box 441133, Moscow, ID 83844, USA; |
| |
Abstract: | Seedling growth and gas exchange responses were measured for two potted seedling trials testing herbicide phytotoxicity to
three important tree species of the Inland Northwest, USA. Media-filled pots were treated with sulfometuron methyl (Oust?) in varying concentrations and planted with seedlings of Larix occidentalis Nutt., Pseudotsuga menziesii var. glauca (Beissn.) Franco, and Pinus monticola Dougl. ex D. Don. Seedlings were grown in two trials to determine the effects of two important residue breakdown factors,
substrate moisture and pH, relative to that of herbicide application rate on seedling health. Changes in seedling height,
root-collar diameter, and root volume were morphologic variables of interest, and physiological variables measured were net
photosynthetic assimilation, stomatal conductance, and transpiration rate. While three levels of media moisture and four levels
of media pH had no effect on seedling performance, most growth and leaf function variables were hindered across application
rate treatments of all three species. Label-recommended dosages resulted in growth suppression levels potentially detrimental
to seedling establishment for all three species. This was most pronounced for Pinus monticola, in particular for root growth, where untreated control seedlings showed 109% more root volume growth than treated seedlings.
We conclude that when possible, a species-specific application rate might be found that balances the benefits of vegetation
control with the phytotoxicity to promote optimal growth gains. |
| |
Keywords: | |
本文献已被 SpringerLink 等数据库收录! |
|