Major Gene Control of Nitrate Reductase Activity in Common Wheat¹

Abstract

Two high‐yielding, short‐statured spring wheats (Triticum aestivum L.), ‘Anza’ and ‘UC 44‐111,’ differ in certain characteristics of N metabolism. Nitrate reductase activity (NRA), measured in vitro on shoots or lamina of seedling plants, was about 8 and 18 µmoles of nitriteproduced/hour/g fresh weight for Anza and UC 44‐111, respectively. The genetic basis for this difference was investigated with an in vitro NRA assay on seedling plants to determine the NRA frequency distributions of parents, F1, F2, reciprocal BCF2 and randomly derived F6 lines. All data were consistent in showing that UC 44‐111 has a single dominant gene (Nra) which accounted for most of the variability observed for NRA.

Aluminum tolerances of two wheat genotypes related to nitrate reductase activities

“…Our results confirmed the finding of Rao et al, (1977) and Gallagher et al, (1980) that UC 44-111 wheat was significantly higher in NR activity than Anza. This genotypic difference persisted in both the presence and absence of varying degrees of Al stress imposed in nutrient solutions.…”

“…Table 7 shows the effects of Al on the nitrate reductase activities during the second NO^-induced cycle (See Materials and Methods). Results confirmed the findings of Rao et al, (1977) and Gallagher et al, (1980) that ÜC 44-111 is higher in NR activity than Anza. They also showed that the NR activities are much higher in tops than in roots and that the NR activities of Anza tops were severely decreased by Al, but those of UC 44-111 tops were not.…”

“…Decreases in the pH of nutrient solutions by weeping lovegrass genotypes were closely associated with the depletion of NH£ from the medium; however, the pH increases observed were not closely connected with NOj depletion as determined by single ion electrodes (Foy, et al, 1981). Gallagher, et al, (1980) reported that the spring wheat genotype 'UC 44-111' was significantly higher in nitrate reductase, (NR) activity than the genotype 'Anza 1 , presumably in the absence of mineral stress, and that this difference was largely explained by a single, dominant gene. Both genotypes are short statured, high yielding and low in protein.…”

“…In fact, at the time of its release, Anza was considered too low in protein for bread wheat and was considered for use as a feed grain in California (Qualset, et al, 1977). UC 44-111 and Anza were similar in abilities to translocate N from vegetative to reproductive tissues (Gallagher, et al, 1980), but UC was more responsive to N fertilization in terms of increased grain yield, total grain protein, total N content per unit land area, light interception at early boot stage and number of kernels per boot spike. UC usually had lower leaf NO3 levels than Anza.…”

Molecular Basis of Aluminium Toxicity in Plants: A Review

“…It is also observed that Al toxicity is closely related to nitrogen metabolism [92]. It was noted that nitrate reductase activity was higher in Al tolerant cultivars, when grown in Al treated nutrient solution [93]. Al interfered with the binding of the cations in the cell wall by the same order of magnitude as their respective influxes whereas phosphate binding was strongly enhanced [94].…”