Herman H. Wiebe

Respiratory Pathway, Flower Color, and Leaf Area of Gladiolus as Factors in the Resistance to Fluoride Injury

Leaf disks were supplied with either glucose-1-14C or glucose-6-14C, and the ratio %14CO2 yield from glucose-6-14C/%14CO2 yield from glucose-1-14C was determined (C6/C1 ratio). Leaves of gladiolus varieties which were sensitive to hydrogen fluoride (Hendrix and Hall, 1958) generally had a higher C6/C1 ratio than leaves of varieties which were resistant to fluoride injury. The results provide circumstantial in vivo support of the hypothesis that the primary fluoride-injury mechanism in intact leaves involves the inhibition of enolase. Resistant varieties may be somewhat more dependent on the pentose phosphate pathway and less dependent on the glycolytic pathway than sensitive varieties.