Fig. 4. (a) Sugar (glucose + fructose) concentration in ripe fruit of tomato
cultivar Counter grown in nutrient solutions containing either low (N1) or high
(N2) nutrient concentration (controls), or after transfer of plants to lower (N2/1)
or higher (N1/2) nutrient concentration. The inset shows the differences
between N2/1 or N1/2 and their corresponding controls as correlated with
time. (b) Sugar content of ripe tomato fruit (N1, N2) as dependent on daily total
radiation (means of the 42 days recorded prior to each harvest date).