Differential effect of soil temperature on iron-deficiency chlorosis in susceptible and resistant subclovers

Iron deficiency, which is most prevalent on calcareous soils, reduces the productivity of susceptible clovers (Trifolium spp.). Factors causing differences in Fe-deficiency chlorosis susceptibility among clover cultivars and species are not well understood. The objective of this study was to determine the influence of soil temperature on chlorosis expression, plant growth, and mineral nutrition of Fe-deficiency chlorosis susceptible and resistant cultivars of subterranean clover (T. subterraneum L.; subclover). Two cultivars of subclover, «Karridale» (susceptible) and «Koala» (T. brachycalycinum Katzn. and Morley; resistant), were grown in a greenhouse on a low-Fe Parrita soil (pH 8.2, clayey, mixed, hyperthermic, shallow Petrocalcic Paleustoll) using a Conetainer (Stuewe and Sons, Inc., Corvallis, OR) culture system with seven soil temperature treatments within the range of 7 to 33 o C [...]