ISSN:
1573-5036
Keywords:
BPDS
;
Cucumis melo L.
;
EDDHA
;
ferric reduction
;
iron efficient
;
iron inefficient
Source:
Springer Online Journal Archives 1860-2000
Topics:
Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
Notes:
Abstract A mutant muskmelon (Cucumis melo L.) with characteristic Fe-deficiency chlorosis symptoms was compared to related cultivars in its ability to obtain Fe via the widely known Fe-stress response mechanisms of dicotyledonous plants. The three cultivars (fefe, the ‘Fe-inefficient’ mutant; Mainstream and Edisto, both ‘Fe efficient’ plants) were grown in nutrient solution in either 0 or 3.5 mg L-1 Fe as FeCl3. None of the three cultivars released ‘reductants’ or ‘phytosiderophores’, but both Edisto and Mainstream produced massive amounts of H+ ions to reduce and maintain the pH of nutrient solutions below pH 4.0. The roots of these two Fe-efficient cultivars were also capable of reducing Fe3+ to Fe2+. These responses maintained green plants, resulted in high leaf Fe in both Edisto and Mainstream, and produced Mn toxicity in Mainstream. The lack of Fe-deficiency stress response in fefe not only affected leaf Fe concentration and chlorosis, but also resulted in reduced uptake of Mn. The importance of reduced Fe (Fe2+) to the Fe-efficient cultivars was confirmed by growing the cultivars with BPDS (4, 7-diphenyl-1, 10-phenanthroline disulfonic acid, a ferrous chelator) and EDDHA [ethylene-diamine di (0-hydroxphenylacetic acid)] (a ferric chelator), and observing increased chlorosis and reduced Fe uptake in BPDS grown plants. The Fe-deficiency response observed in these cultivars points out the diversity of responses to Fe deficiency stress in plants. The fefe mutant has a limited ability to absorb Fe and Mn and perhaps could be used to better understand Mn uptake in plants.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00011860
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