CL?-Fluxe,Akkumulation und Transport in abgeschnittenen Mais-Wurzeln |
| |
Authors: | Josef Weigl |
| |
Institution: | (1) Botanisches Institut der Technischen Hochschule Darmstadt, Darmstadt, Deutschland |
| |
Abstract: | Summary Fluxes, accumulation and transport rates of Cl- in excised corn roots were investigated.Flux equilibrium in 5×10-4M KCl was not reached within an experimental period of 28 hr.Transport of Cl- (5×10-4M KCl) through the xylem of 4–6 cm long excised corn roots had a lag of 1–2 hr. From 6 to 28 hr rates of accumulation and transport were nearly constant (5×10-4M KCl). The velocity of volume-flow within the xylem was 1.5–2 cm hr-1 (5×10-4M KCl).
36Cl--efflux through the cut end of roots preloaded in K36Cl of low concentration exhibits a discontinuity which is explained by addition of two fluxes: efflux of ions concentrated in the xylem (and symplasm) plus efflux from the vacuoles through the xylem.Accumulation of Cl- by excised roots approaches a maximum level (Jackson and Edwards, 1966). Influx rates remain constant while efflux rates increase with time. It is shown in this paper that the flux of Cl- through the xylem becomes a large proportion of the influx across the plasmalemma. Flux rates suggest that more than 50% of the Cl- ions transported to the xylem passed through a vacuole (5×10-4M KCl; 20–28 hr). |
| |
Keywords: | |
本文献已被 SpringerLink 等数据库收录! |
|