Table I.

Effect of varying mannose and phosphate supply on adenine nucleotide contents, ATP/ADP ratio, and AEC in maize root tips

		ATP	ADP	AMP	Σ AdN	ATP/ADP	AEC
	nmol/tip
Control		1,836	360	<2	2,197	5.1	0.91
Starvation		1,147	225	<2	1,373	5.0	0.91
Glu	2 mm	1,205	241	<2	1,447	4.9	0.90
Man	2 mm
Pi	0 mm	313	165	11	489	1.9	0.81
	0.25 mm	475	228	22	725	2.1	0.81
	10 mm	700	188	5.7	894	3.7	0.89
	30 mm	762	141	<2	904	5.4	0.92
	100 mm	13	12	2.1	27	1.1	0.69
Man	10 mm
Pi	0 mm	367	275	74	716	1.3	0.70
	0.25 mm	387	243	61	691	1.6	0.74
	10 mm	447	236	77	760	1.9	0.74
	30 mm	446	215	47	708	2.1	0.78
	100 mm	107	35	5.3	147	3.1	0.85

Root tips were incubated for 48 h with either 2 or 10 mm mannose, in the presence of 0, 0.25, 10, 30, or 100 mm Pi, and analyzed as described in “Materials and Methods.” Control, T0 control root tips. Starvation and Glu 2-mm, 48-h-starved and 2-mm Glu-fed root tips, respectively. ΣAdN, Sum of adenine nucleotides. These data represent the mean of four independent experiments. sd are below 15%.