chapter  7
Silicon and Floricultural Crops: Evaluation of Silicon Uptake and Deposition in Floricultural Plants
Pages 16

Silicon (Si) is still deemed to be a nonessential nutrient for the majority of plant species, although its uptake has been found to be beneficial for improving resistance to insects, pathogens, drought, and heavy metals, and for crop quality and yield in some plant species. Although not extensively studied, the addition of Si to nutrient solutions has enhanced flower quality in many ornamental plants, such as begonias, carnations, chrysanthemums, gerberas, kalanchoes, marigolds, miniature roses, petunias, phalaenopsis, poinsettias, salvias, sunflowers, torenias,

7.1 Introduction .......................................................................................................................... 118 7.2 Si in Floricultural Plants ....................................................................................................... 118

7.2.1 Ajuga multiflora ........................................................................................................ 118 7.2.2 Begonia ..................................................................................................................... 118 7.2.3 Calendula .................................................................................................................. 121 7.2.4 Carnation .................................................................................................................. 121 7.2.5 Chrysanthemum ........................................................................................................ 121 7.2.6 Cotoneaster wilsonii ................................................................................................. 121 7.2.7 Gerbera ..................................................................................................................... 122 7.2.8 Kalanchoe ................................................................................................................. 122 7.2.9 Marigold ................................................................................................................... 122 7.2.10 Nephrolepis exaltata ................................................................................................. 122 7.2.11 Phalaenopsis ............................................................................................................. 122 7.2.12 Poinsettia .................................................................................................................. 123 7.2.13 Rose .......................................................................................................................... 123 7.2.14 Salvia splendens ....................................................................................................... 123 7.2.15 Sunflower .................................................................................................................. 123 7.2.16 Zinnia ........................................................................................................................ 123

7.3 Si Uptake and Deposition in Floricultural Plants .................................................................124 7.3.1 Positive Effects .........................................................................................................124 7.3.2 Negative Effects ........................................................................................................124 7.3.3 Si Uptake and Deposition in Floricultural Plants .....................................................124 7.3.4 Lsi Genes .................................................................................................................. 127

7.4 Conclusions and Future Prospects ........................................................................................ 128 References ...................................................................................................................................... 128

and zinnias. The reported effects vary and depend strongly on plant species. The beneficial effects of Si are usually more apparent under biotic or abiotic stress. Thus, the addition of Si to the nutrient solution of plants has also shown positive effects in floristic crops. However, most floricultural plants studied were low Si accumulators. The low Si uptake by floricultural plants suggests that they may lack homologs to Lsi genes, which encode the Si transporter in rice, and thus may not have the underlying molecular mechanisms to accumulate significant amounts of Si in the tissues. The objective of this chapter is to summarize research on the effects of Si supplementation on plant growth and changes in stress resistance under abiotic and biotic stress conditions, and also to evaluate Si uptake and deposition in floricultural crops.