Some Studies of the Adsorption of Zinc Sulfate in Thompson Seedless Grape Canes.

Abstract

Little leaf of gra.pevines is corrected by applying zinc to the vine (1, 2,3,4,5,6 RESEARCH EXPERIMIENT 1: A dlormant cane was prepared and the amount of water in the vessels of a 1.5-m section was determined by sucking the water out into a trap with a vacuum. This section of grape cane yielded 3.5 ml of water by this method. A 1-ml aliquot of the low activity Zn65SO4 solution was diluted to 4 ml with distilled water and placed in the glass tubing attached to the base of another cane. This amount of solution would just approximately displace the solution in the cane. The tip of this cane was cut off at 1.62 m andl the solution allowed to flow through it. The exudate, 3.8 ml in all, was collected in 1 ml lots and examined for radiation. The cane was then pushed through a cylindrical sample chamber having 5.7 cm thick lead walls for radioactivity measurements (Tracer Laboratory). The Geiger-MIuller tube was an end-on type having a thin mica window of 2.54 cm diameter (Tracer Laboratory), and of about 1.8 mg/cm2. The

The Mobility of 65zn In Trifolium Subterraneu M L. and Antirrhinum Majus L.

“…The evidence obtained previously by Millikan and Hanger (1967 a) on the recirculation of 65Zn in young pear trees following bark injection also supports the work by Hewitt and Gardner (1956).…”

“…It is postulated that the recirculated zinc came from the conducting strands, and that movement was by a cation exchange process, similar to that demonstrated by Hewitt and Gardner (1956) in grapevines. The evidence obtained previously by Millikan and Hanger (1967 a) on the recirculation of 65Zn in young pear trees following bark injection also supports the work by Hewitt and Gardner (1956).…”

Translocation of Calcium. Exchange versus Mass Flow

“…This suggestion could be justified from an experiment of Hewett and Gardner (8) showing an adsorption of zinc ions passing through sections of grape canes.…”

Effects of Chelation and of Various Cations on the Mobility of Foliar-Applied 65zn in Subterranean Clover

“…The most rapid movement of the 65Zn into the laminae of non-injected leaves resulted from the reduction of its charge by the chelating agent EDTA, thus allowing it to by-pass the exchange sites in the vessels. Hewitt and Gardner (1956) have also shown that the movement of radioactive zinc in grapevine canes was by a process of cation exchange, whereby the adsorbed 65Zn was displaced from the exchange sites by non-radioactive zinc or by hydrogen ions and thereby made to move along the vessels.…”