ARS | Publication request: EVALUATING SILICON UPTAKE IN COMMON FLORICULTURE PLANTS

Submitted to: Silicon in Agriculture Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: June 15, 2005
Publication Date: October 20, 2005
Citation: Frantz, J., Pitchay, D., Locke, J.C., Krause, C.R. 2005. Evaluating silicon uptake in common floriculture plants. Silicon in Agriculture Proceedings. p.125.

Technical Abstract: Silicon (Si) is not commonly added in floriculture crop fertilizer recipes in the United States because it is not considered to be an essential plant nutrient. Given the growing body of information showing a clear, beneficial effect on plant growth, inclusion of Si in fertilizer recipes could be a large benefit to greenhouse plant producers because more production is using soilless media that are devoid of Si. Therefore, Si would have to be supplied either as a foliar spray or nutrient solution amendment. Most of the common floriculture plant species have not been critically evaluated for Si uptake, and documenting that uptake is an initial step in determining the usefulness of Si inclusion for greenhouse management. We investigated adding Si to New Guinea impatiens (Impatiens hawkeri Bull), impatiens (Impatiens wallerana Hook.f), marigold (Tagetes erecta L.), geranium (Pelargonium × hybrida ), dianthus (Dianthus spp.), verbena (Verbena× hybrida Voss) and orchid (Phalaenopsis spp.). Using SEM, energy dispersive X-ray analysis, and ICP analysis, Si content and location was determined. Of these seven species, four contained significant concentrations of Si in deposits on the leaf margin. Si was not just localized on the leaf margin in marigold, but rather distributed uniformly throughout the leaf parenchyma cells, based on x-ray analysis. There was no Si in stem or root sections of any of the plants. Regardless of its localization, the fact that Si is taken up by these plants opens the possibility for Si-activation of plant defense mechanisms and provides an opportunity to ameliorate micronutrient toxicity. This information and other growth characteristics will be used as a first step in determining the likelihood of using Si as a beneficial element in greenhouse fertilizer solutions for higher quality bedding plants with fewer agrochemical inputs in the United States.