Five clonal myrobalan rootstocks for peach (Mr.S.1/3, 1/6, 1/16, 2/3 and 2/8) were assessed for tolerance to lime-induced chlorosis and compared to Mr.S.2/5, rootstock known for its good level tolerance. The experiments were carried out on hydroponic culture in a greenhouse and adding sodium bicarbonate (0, 10 and 20 mM concentrations) to the Hoagland's modified nutrient solution. The evaluation was based on morphological (growth measured as fresh weight increment) and physiological (leaf chlorophyll concentration and root cationic exchange capacity) parameters. Therefore active iron concentration and ferric-reducing capacity were investigated and determined on three clones chosen for their different tolerance showed in the trial. The screening revealed a different behaviour of the selections respect to Mr.S.2/5. So morphological as physiological markers Showed that some myrobalan rootstocks (Mr.S.1/3, 1/6 and 2/8) presented a lightly minor tolerance than Mr.S.2/5. Weight increment and chlorophyll concentration were higher in Mr.S.1/6, 2/5 and particularly in Mr.S.2/8. On the contrary Mr.S.1/6 and 2/3 showed low chlorophyll concentration and low RCEC in every stress condition. Active iron and ferric-reducing capacity were higher in Mr.S.2/5 and 2/8 than in Mr.S.2/3. RCEC and Fe(III)-reducing capacities showed in evidence that tolerant rootstocks increased their power to uptake iron more than the less tolerant ones (Mr.S 1/16 and 2/3). Mr.S 1/3, 1/6, 2/8 and particularly 2/5 showed high levels of RCEC at 10 and 20 mM concentrations of NaHCO3. In conclusion the analysis of all the parameters considered together allowed to identify among the clones a range of adaptability to the lime-induced chlorosis conditions, and therefore the physiological responses investigated revealed that the best level of tolerance was shown from the clones able to greatly increase iron reduction uptake at the root system level, and iron translocation-form activation at the leaf system level
Physiological response of clonal myrabolan rootstocks under lime-induced chlorosis
VITI, RAFFAELLA;CINELLI, FABRIZIO;
1998-01-01
Abstract
Five clonal myrobalan rootstocks for peach (Mr.S.1/3, 1/6, 1/16, 2/3 and 2/8) were assessed for tolerance to lime-induced chlorosis and compared to Mr.S.2/5, rootstock known for its good level tolerance. The experiments were carried out on hydroponic culture in a greenhouse and adding sodium bicarbonate (0, 10 and 20 mM concentrations) to the Hoagland's modified nutrient solution. The evaluation was based on morphological (growth measured as fresh weight increment) and physiological (leaf chlorophyll concentration and root cationic exchange capacity) parameters. Therefore active iron concentration and ferric-reducing capacity were investigated and determined on three clones chosen for their different tolerance showed in the trial. The screening revealed a different behaviour of the selections respect to Mr.S.2/5. So morphological as physiological markers Showed that some myrobalan rootstocks (Mr.S.1/3, 1/6 and 2/8) presented a lightly minor tolerance than Mr.S.2/5. Weight increment and chlorophyll concentration were higher in Mr.S.1/6, 2/5 and particularly in Mr.S.2/8. On the contrary Mr.S.1/6 and 2/3 showed low chlorophyll concentration and low RCEC in every stress condition. Active iron and ferric-reducing capacity were higher in Mr.S.2/5 and 2/8 than in Mr.S.2/3. RCEC and Fe(III)-reducing capacities showed in evidence that tolerant rootstocks increased their power to uptake iron more than the less tolerant ones (Mr.S 1/16 and 2/3). Mr.S 1/3, 1/6, 2/8 and particularly 2/5 showed high levels of RCEC at 10 and 20 mM concentrations of NaHCO3. In conclusion the analysis of all the parameters considered together allowed to identify among the clones a range of adaptability to the lime-induced chlorosis conditions, and therefore the physiological responses investigated revealed that the best level of tolerance was shown from the clones able to greatly increase iron reduction uptake at the root system level, and iron translocation-form activation at the leaf system levelI documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
