The Effect of Zinc on Germination in Species of the Genus Echium (Family Boraginaceae)

The effect of zinc on seed germination in two species of the genus ( J.F. Gmelin and L.) was investigated. Zinc was used as sulphate in three different concentrations: 100 mg∕ l; 200 mg ∕ l și 300 mg ∕ l; the treatment was applied to the seeds before germination, the exposure time being short (4 hours and 8 hours). Seed germination was monitored daily for a period of 14 days. The effect of treatment on seed germination in the test species was assessed by calculating four germination indicators: final germination percentage (FGP), germination index (GI), mean germination time (MGT) and coefficient of rate germination (CRG). The results show the following: the seeds of germinate faster than those of ; statistically insignificant changes in the indicators associated with germination, except for GI in for the 8 hours exposure time; reduction of germination percentage (in both species) and increase in germination time (more evident in ) with increasing exposure time. The test species showed tolerance throughout the germination process to the zinc concentrations used.