Quantitative relationships between boron and mannitol concentrations in phloem exudates of Olea europaea leaves under contrasting boron supply conditions

dc.contributor.author	Liakopoulos, G	en
dc.contributor.author	Stavrianakou, S	en
dc.contributor.author	Nikolopoulos, D	en
dc.contributor.author	Karvonis, E	en
dc.contributor.author	Vekkos, K-A	en
dc.contributor.author	Psaroudi, V	en
dc.contributor.author	Karabourniotis, G	en
dc.date.accessioned	2014-06-06T06:49:30Z
dc.date.available	2014-06-06T06:49:30Z
dc.date.issued	2009	en
dc.identifier.issn	0032079X	en
dc.identifier.uri	http://dx.doi.org/10.1007/s11104-009-9923-2	en
dc.identifier.uri	http://62.217.125.90/xmlui/handle/123456789/4637
dc.subject	Borate-polyol complexes	en
dc.subject	Boron remobilization	en
dc.subject	Cellular boron	en
dc.subject	Mannitol translocation	en
dc.subject	Olea europaea L.	en
dc.subject	Phloem sap exudate	en
dc.subject.other	alcohol	en
dc.subject.other	boron	en
dc.subject.other	cultivation	en
dc.subject.other	dicotyledon	en
dc.subject.other	exudation	en
dc.subject.other	phloem	en
dc.subject.other	remobilization	en
dc.subject.other	sap flow	en
dc.subject.other	translocation	en
dc.subject.other	Olea europaea	en
dc.title	Quantitative relationships between boron and mannitol concentrations in phloem exudates of Olea europaea leaves under contrasting boron supply conditions	en
heal.type	journalArticle	en
heal.identifier.primary	10.1007/s11104-009-9923-2	en
heal.publicationDate	2009	en
heal.abstract	Boron remobilization (BR) occurs in plants that form and export phloem-mobile borate-polyol complexes. Previous studies demonstrate that a quantitative relationship exists between polyol translocation and BR. Here we investigate if mannitol translocation is quantitatively related to BR in olive plants thus allowing acclimation to boron limiting conditions. Plants were cultivated under different boron supply ranging from adequate (23 μM) to insufficient or zero supply (0.5 μM or 0 μM). Measurement of boron in the leaf phloem sap exudates (BP) of olive leaves of low or zero boron supply treatments showed that, whereas boron was remobilized, its absolute amounts in the phloem were lower compared to the control. However, BR from source leaves at 0.5 μM or 0 μM was maintained at relatively high levels in regard to the amounts of boron available in the cells of these leaves, indicating a strategy of the source leaves to remobilize boron by depleting their cell sap boron pool. Concurrently, in the above treatments, leaf phloem mannitol (MP) was up to two-fold higher, resulting in a up to five-fold higher ratio of mannitol to boron in the phloem (MP/BP), compared to the control. Furthermore, both MP and MP/BP were negatively correlated with cell sap boron concentration of the leaves indicating the trend for BR under boron limitation. It is concluded that, in this plant species, mannitol concentrations in the leaf phloem may be involved in the promotion of BR under inadequate external supply of boron. © Springer Science+Business Media B.V. 2009.	en
heal.journalName	Plant and Soil	en
dc.identifier.issue	1	en
dc.identifier.volume	323	en
dc.identifier.doi	10.1007/s11104-009-9923-2	en
dc.identifier.spage	177	en
dc.identifier.epage	186	en