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Improving NaCl resistance of red-osier dogwood: role of CaCl2 and CaSO4

“…However, the plants produced were significantly shorter than the salttreated plants not exposed to CaSO 4 . Previous results (Renault et al 2001) have also shown that 50 mM Na 2 SO 4 reduced plant biomass and shoot height of redosier dogwood to a greater degree than NaCl in equimolar Na + concentrations although the osmotic potential of the 50 mM Na 2 SO 4 solution (−0.43 MPa) was higher than for the NaCl solution (−0.56 MPa) suggesting specific anion effects. Although sulfur is required as a macronutrient for plant growth, a high concentration of SO 2À 4 can lead to the formation of sulfoxide that can inhibit cell division (Strogonov 1974).…”

“…We found that the negative effects of 50 mM Na 2 SO 4 on shoot height and stem cell wall dry weight of red-osier dogwood could be alleviated by the presence of 5 mM CaCl 2 (Renault 2005). However, our results have shown that 50 mM Na 2 SO 4 caused a more severe reduction in root and shoot dry biomass of red-osier dogwood than equimolar Na + concentration from NaCl (Renault et al 2001). Therefore, it cannot be speculated that the interaction of NaCl and various Ca 2+ salts will be similar to a Na 2 SO 4 and Ca 2+ interaction.…”

“…Previous studies using hydroponics have shown that the root/shoot ratio of red-osier Table 7 Calcium content of red-osier dogwood tissues (root, stem, leaf and lateral shoot) exposed to 50 mM NaCl in presence or absence of additional Ca 2+ for 40 days dogwood was not affected by 50 mM NaCl as both root and shoot biomass were equally reduced by the salt (Renault et al 2001). This difference in plant responses can be attributed to the availability of ions.…”

“…It is a coldand flood-tolerant species that can also grow on dry sites. This species is an excellent soil stabilizer that has potential for early stages of reclamation of some saltaffected areas in Western Canada as a result of oil sand mining (Renault et al 2001). Our earlier studies (Renault et al 2001;Renault 2005) have shown that Na + was preferentially stored in the root tissues of redosier dogwood exposed to NaCl and Na 2 SO 4 suggesting that the seedlings could control the transport of Na + from root to shoot thus limiting shoot injury.…”

“…This species is an excellent soil stabilizer that has potential for early stages of reclamation of some saltaffected areas in Western Canada as a result of oil sand mining (Renault et al 2001). Our earlier studies (Renault et al 2001;Renault 2005) have shown that Na + was preferentially stored in the root tissues of redosier dogwood exposed to NaCl and Na 2 SO 4 suggesting that the seedlings could control the transport of Na + from root to shoot thus limiting shoot injury. We found that the negative effects of 50 mM Na 2 SO 4 on shoot height and stem cell wall dry weight of red-osier dogwood could be alleviated by the presence of 5 mM CaCl 2 (Renault 2005).…”