Rick Jones

Electron Microprobe Analysis of the Distribution of Silicon and Other Elements in Rice Leaf Epidermis

Using electron microprobe analysis, significant amounts of silicon were detected in a few long epidermal cells, mostly along their cell walls, in the silica cells, and in the trichomes of both surfaces of the leaf blade and leaf sheath of the rice (Oryza) plant. This analysis did not reveal detectable amounts of silicon in the stomatal apparatuses of these organs. In the ligule, silicon is present in significant quantities in some of the epidermal cells, while in other long epidermal cells no significant amounts of silicon were detected. The effect of accumulation of large quantities of silicon in the long epidermal cells of the ligule on the accumulation pattern of K, Ca, Mg, P, Mn, Fe, and Na is described. This effect of silicon, particularly on the accumulation of potassium, is discussed.

Urease and urea amidolyase: Determination of activity in liverworts

Abstract Using highly sensitive techniques, we have investigated urea degradation in the liverworts and found that they have high urease but no detectable urea amidolyase activity.