Ectomycorrhizal Fungus Scleroderma bermudense to Improve the Salt Tolerance in Coccoloba uvifera (L.)
Mijail Bullain1, Fatoumata Fall2, Raul Lopez3, Ludovic Pruneau4, Amadou Ba5, Bettina Eichler-Löbermann6
1Granma University, Plant Biotecnology Study Center, Cuba
Coccoloba uvifera (L.) L. (Polygonaceaea), also named seagrape, is a woody plant often subject to high levels of salinity along the Atlantic, Caribbean and Pacific coasts of the American tropics and subtropics. It is an important tree for edible fruits and mushrooms, ornamental plantings and coastal windbreaks along Caribbean beaches and roadsides. We studied the effect of the ectomycorrhizal (ECM) fungus Scleroderma bermudense on growth, photosynthesis and transpiration rates, chlorophyll fluorescence and content, K/Na and Ca/Na homeostasis, and water status of two Cuban provenances of Coccoloba uvifera seedlings exposed to four levels of salinity (0.0, 54.7, 164.1 and 273.5 mM NaCl equivalent to 0.02, 5, 15 and 25 dS m -1, respectively). The results indicated that S. bermudense improved the salt tolerance in seagrape seedlings. There were no differences in terms of growth performance, nutritional and physiological functions between the two ECM seagrape provenances in response to salt stress. The reduction of the Na concentration and the increase of K and Ca favoured a higher K/Na and Ca/Na ratio, respectively, in the tissues of the ECM seedlings. Furthermore, the beneficial effects of ECM symbiosis on the photosynthetic and transpiration rates, chlorophyll fluorescence and content, stomatal conductance and water status resulted in the improved growth performance of the seagrape provenances exposed to salt stress. Seagrape in symbiosis with S. bermudense only may benefit for the individual plant but, more importantly, may result in the development of ornamental plantings and coastal windbreaks along beaches and roadsides in Cuba.
Keywords: Chlorophyll, ectomycorrhiza, photosynthesis, seagrape, water status
Contact Address: Bettina Eichler-Löbermann, Rostock University, Agricultural and Environmental Faculty, Justus-von-Liebig-Weg 6, 18059 Rostock, Germany, e-mail: bettina.eichleruni-rostock.de