Changes in the concentrations of the individual sugars of the walls and locular contents of tomato fruit during ripening have been studied. The major sugars were glucose and fructose together with much smaller amounts of sucrose and myoinositol. During the initial stages of development the fruit contained approximately twice as much glucose as fructose, but with approaching maturity and the onset of ripening the glucose/fructose ratio declined to less thaii unity. On a per fruit basis the distribution of the major sugars between the walls and locular contents was about 3 : 1 at the green stage, falling to 2 : 1 as the fruit ripened.Total reducing sugars (% fresh weight or per fruit) increased markedly between the mature green and green-yellow stages with a tendency to decrease with subsequent ripening. These changes were predominantly influenced by changes in fructose content, with glucose changing little. The concentrations of sucrose and myoinositol, both less than 0.05 % fresh weight, declined with ripening.The green areas of the outer walls of "blotchy" fruit contained much less glucose and fructose than did the walls of normal mature green fruit, while the red areas contained amounts similar to those encountered in normally ripened red fruit.

Lettuce plants grown in beds of soil previously fumigated with methyl bromide accumulated water-extractable bromide, the amount present in the tissues depending on the concentration of inorganic bromide produced in the soil by the breakdown of the fumigant. Samples of lettuce plants from commercial nursery soils fumigated with methyl bromide at rates of 1-2 lb/ IOO ft2 (49-98 g/m2) gave rise to soil bromide levels of I 1-61 ,ug/g. The corresponding bromide concentrations in the plants ranged from 1.6 to

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SUMMARY Tomato plants grown in soil previously fumigated with methyl bromide accumulated inorganic bromide in the foliage. The concentration present depended on the rate of application of methyl bromide to the soil and on the interval between, soil fumigation and planting, two factors determining the concentration in the soil of inorganic bromide arising from the breakdown of the fumigant. The concentration of bromide in the leaves decreased from the base to the tip of the plant, and increased with the age of the tissue. Bromide was accumulated in the fruit, but to a lesser extent than in the leaves. Mature fruit from plants grown in soil fumigated at the commercially applied rate of 1.5 lb/100 ft2 (73 g/m2) contained at the most 45 μg/g of fresh tissue, and generally not more than half this value. The concentration of bromide in fruit was related to the concentration of inorganic bromide present in the soil, but not to the state of ripeness or the position of the fruit on the plant. Similar results were obtained for leaves and fruit from plants grown in soil supplemented with inorganic bromide.