Table 1.

Effect of inhibitors on NO₃⁻ net uptake into Cleopatre mandarine roots

	cHATS		iHATS		LATS
Treatment	NO3− net uptake	% inhibition	NO3− net uptake	% inhibition	NO3− net uptake	% inhibition
Control	0.103±0.010		0.197±0.012		0.417±0.030
2,4-DNP	0.051±0.001*	50	0.003±0.001*	98	0.109±0.011*	74
DCCD	0.036±0.002*	65	0.056±0.003*	72	0.148±0.012*	64
DES	0.031±0.012*	70	0.043±0.002*	78	0.217±0.020*	48

The cHATS, iHATS and cHATS+LATS activities were measured in 0.2 mM NO₃⁻, uninduced seedlings, 0.2 mM NO₃⁻, induced seedlings by 3 d, and 3 mM NO₃⁻, uninduced seedlings, respectively. iHATS and LATS were calculated by subtracting the NO₃⁻ net uptake measured at 0.2 mM NO₃⁻ in uninduced seedlings from these measured at 0.2 mM NO₃⁻ in induced seedlings and, 3 mM NO₃⁻ in uninduced seedlings, respectively. Each data point is the average of 24 replicates with ± SE.

^*Significant at 5% level respect to the control. NS not significant. NO₃⁻ net uptake is expressed as µmol g⁻¹ root FW h⁻¹.