Leaf structural changes associated with iron deficiency chlorosis in field-grown pear and peach: physiological implications

The final version is available at: http://www.springerlink.com/content/y62g0r6712184032/fulltext.pdfPlants grown in calcareous, high pH soils develop Fe deficiency chlorosis. While the physiological parameters of Fe-deficient leaves have been often investigated, there is a lack of information regarding structural leaf changes associated with such abiotic stress. Iron-sufficient and Fe-deficient pear and peach leaves have been studied, and differences concerning leaf epidermal and internal structure were found. Iron deficiency caused differences in the aspect of the leaf surface, which appeared less smooth in Fe-deficient than in Fe-sufficient leaves. Iron deficiency reduced the amount of soluble cuticular lipids in peach leaves, whereas it reduced the weight of the abaxial cuticle in pear leaves. In both plant species, epidermal cells were enlarged as compared to healthy leaves, whereas the size of guard cells was reduced. In chlorotic leaves, bundle sheaths were enlarged and appeared disorganized, while the mesophyll was more compacted and less porous than in green leaves. In contrast to healthy leaves, chlorotic leaves of both species showed a significant transient opening of stomata after leaf abscission (Iwanoff effect), which can be ascribed to changes found in epidermal and guard cells. Results indicate that Fe-deficiency may alter the barrier properties of the leaf surface, which can significantly affect leaf water relations, solute permeability and pest and disease resistance.This study was supported by the Spanish Ministry of Science and Education (MEC, grants AGL2006-01416 and AGL2007-61948, co-financed with FEDER), the European Commission (ISAFRUIT project, Thematic Priority 5-Food Quality and Safety of the 6th Framework Programme of RTD; Contract no. FP6-FOOD-CT-2006-016279) and the Aragón Government (group A03). V.F. was supported by a “Juan de la Cierva”-MEC post-doctoral contract, co-financed by the European Social Fund. T.E. was supported by the CAI Europa XXI for a short term stay at the EEAD-CSIC.Peer reviewe

Leaf structural changes associated with iron deficiency chlorosis in field-grown pear and peach: physiological implications

The final version is available at: http://www.springerlink.com/content/y62g0r6712184032/fulltext.pdfPlants grown in calcareous, high pH soils develop Fe deficiency chlorosis. While the physiological parameters of Fe-deficient leaves have been often investigated, there is a lack of information regarding structural leaf changes associated with such abiotic stress. Iron-sufficient and Fe-deficient pear and peach leaves have been studied, and differences concerning leaf epidermal and internal structure were found. Iron deficiency caused differences in the aspect of the leaf surface, which appeared less smooth in Fe-deficient than in Fe-sufficient leaves. Iron deficiency reduced the amount of soluble cuticular lipids in peach leaves, whereas it reduced the weight of the abaxial cuticle in pear leaves. In both plant species, epidermal cells were enlarged as compared to healthy leaves, whereas the size of guard cells was reduced. In chlorotic leaves, bundle sheaths were enlarged and appeared disorganized, while the mesophyll was more compacted and less porous than in green leaves. In contrast to healthy leaves, chlorotic leaves of both species showed a significant transient opening of stomata after leaf abscission (Iwanoff effect), which can be ascribed to changes found in epidermal and guard cells. Results indicate that Fe-deficiency may alter the barrier properties of the leaf surface, which can significantly affect leaf water relations, solute permeability and pest and disease resistance.This study was supported by the Spanish Ministry of Science and Education (MEC, grants AGL2006-01416 and AGL2007-61948, co-financed with FEDER), the European Commission (ISAFRUIT project, Thematic Priority 5-Food Quality and Safety of the 6th Framework Programme of RTD; Contract no. FP6-FOOD-CT-2006-016279) and the Aragón Government (group A03). V.F. was supported by a “Juan de la Cierva”-MEC post-doctoral contract, co-financed by the European Social Fund. T.E. was supported by the CAI Europa XXI for a short term stay at the EEAD-CSIC.Peer reviewe