Response to increasing rates of boron and NaCl on shoot proliferation and chemical composition of in vitro kiwifruit shoot cultures

Abstract

The in vitro response of kiwifruit (Actinidia deliciosa) to increasing concentrations of boron (B) and NaCl in the culture medium was studied. Kiwifruit shoot cultures were grown in vitro for 12 weeks on an MS medium containing two B concentrations (0.1 and 2 mM) combined with five NaCl concentrations (0, 10, 20, 40 and 80 mM). Kiwifruit produced the longest shoots with 2 mM B when NaCl concentration was 0-20 mM. More shoots were produced with 2 mM B for all NaCl treatments. More shoots were produced with 2 mM B and 10 and 20 mM NaCl. High B concentrations in the culture medium significantly increased shoot proliferation. Explants exhibited a moderate chlorotic appearance with 40 mM NaCl and shoots died with 80 mM NaCl. With 2 mM B, the B concentration of explants was 5-9· greater for the various NaCl treatments compared to the control. Increasing the NaCl concentration from 10 to 80 mM, resulted in higher Na and Cl concentrations in explants for all B treatments, while K and Ca concentrations decreased. Phosphorus concentration in the explants was significantly increased by increasing the NaCl concentration reaching a maximum value at 80 mM NaCl for the two B concentrations.

Physiological and growth changes in micropropagated Citrus macrophylla explants due to salinity

“…Among the different NaCl concentrations applied, 30 mM NaCl did not significantly reduce the productivity of the explants, and produced significant increases of the fresh and dry weights with respect to 0 mM NaCl. Similar results have been observed in other woody species (Singh et al, 2000;Sotiropoulos and Dimassi, 2004). Flowers and Läuchli (1983) reported that, at low concentrations, NaCl exerts a significant positive effect on shoot proliferation in vitro due to the increased osmolarity.…”

“…This pattern, the result of increasing NaCl in the medium, is a common and expected in vitro response and has been reported for many species (Sotiropoulos, 2007;Sotiropoulos and Dimassi, 2004). For plants with a poor ability to exclude saline ions, marked injury in older leaves can occur within days (Munns, 2002).…”

Responses of the cherry rootstock to salinity in vitro

“…However, Fe and Cu concentrations of explants were not significantly affected by NaCl levels in the culture media (Table 3). These results are in parallel to those of Sotiropoulos and Dimassi (2004) and Shiyab et al (2003) who worked with kiwifruit and sour orange shoots in vitro, respectively. In contrast increasing NaCl concentration in the growth medium raised Zn acquisition significantly (Table 3).…”

Effect of NaCl and CaCl2 on the antioxidant mechanism of leaves and stems of the rootstock CAB-6P (Prunus cerasus L.) under in vitro conditions

“…The observed increase in Na + and Cl -concentrations, as the result of NaCl salinity, is a common and expected response and has been also reported for many species (Sotiropoulos and Dimassi 2004;Sotiropoulos 2007). On the contrary, sweet cherry rootstock Gisela-5 presented unaffected or reduced Cl concentration under NaCl stress leading to the suggestion that the explants excluded Cl effectively.…”