Rhizosphere Acidification is Not Part of the Strategy I Iron Deficiency Response of Vaccinium arboreum and the Southern Highbush Blueberry

Summary

Vaccinium arboreum (VA) is a wild blueberry species that exhibits wider soil pH tolerance and greater ability for iron and nitrate uptake than cultivated Vaccinium species, including southern highbush blueberry (SHB, V. corymbosum interspecific hybrids). The ability of VA and SHB to respond to iron deficiency by rhizosphere acidification was investigated. Rooted cuttings of the VA genotype FL09-502 and SHB ‘Emerald’ were transplanted to a hydroponic system filled with complete nutrient solution. After 14 days of acclimation at 45 µ m iron, plants were transferred to unbuffered nutrient solutions containing 90 or 10 µ m iron. ‘Emerald’ and FL09-502 plants grown in 10 µ m iron exhibited less iron uptake and lower chlorophyll, total iron, and active iron contents than plants grown in 90 µ m i