19191 HORTICULTURE. 647 



approximately 1.5 per cent total sugar as Invert sugar, 0.7 per cent sucrose, 

 and 0.8 per cent free-reducing substances. Reversibility of the chief processes 

 involved in the sugar depletion, resulting in an equilibrium between the rate 

 of sugar loss and the rate of sugar formation, would account for the cessation 

 of actual sugar loss. 



Raising the temperature hastens the attainment of the equilibrium positions, 

 which seems to be about the same for all temperatures. At 30° C. (86° F.), 50 

 per cent or most of the total sugar loss occurs during the first 2'1 hours of 

 storage. At 20°, 25 per cent, and at 10°, or good refrigerator temperature, only 

 about 15 per cent is depleted during the same period. The rate of sugar loss, 

 until it reaches 50 per cent of the initial total sugar and GO per cent of tne 

 sucrose, is doubled for every increase of 10° up to 80°. 



Respiration in green corn is comparatively high when the corn is first picked, 

 but falls off rapidly with storage. Respiration accounts for only a small part 

 of the actual decrease in the percentage of sugar in the corn during the con- 

 secutive 24-hour periods of storage, even at 30°. One ton of husked green sweet 

 corn during the first 24 hours of storage at 30° would lose approximately 3.2 

 lbs. of sugar on account of respiration. Respiration may become indirectly 

 a more important factor in accelerating the depletion of sugar by raising the 

 temperature on the inside of large piles of gi'een com. 



Most of the decrease In the percentage of sugar in green sweet corn during 

 storage is attributed to condensation of polysaecharids, chiefly starch. 



Greenhouse tomato growing' in Virginia, H. H. Zimmerley {Virginia Truck 

 Sta. Bid. 26 {1919), pp. 3-23, figs. 2). — Practical directions are given for green- 

 house tomato culture. Including the control of insects and fungus diseases. 

 Some data on investigations conducted at the station are also Included. 



In the fall of 1915 a test with the variety Bonny Best was conducted to de- 

 termine the effect on yield of different planting distances. Plants were set 

 18, 24, and 30 in. apart in 30 in. rows. The 18 in. planting distance attained 

 the highest yield with 23.3 oz. of fruit to the square foot of bed area ; the 24-in. 

 distance gave a yield of 23 oz. to the square foot; and the 30-in. distance, a 

 yield of only 20.7 oz. per square foot. By Increasing the spacing from 18 to 

 24 in. the additional yield per plant was practically sufficient to compensate 

 for the increased bed area. The difference in the size of the fruit produced in 

 the three plats was not sufficient to affect their mai'ket values. 



Beginning in the fall of 1915 and continuing through three successive seasons 

 an experiment was conducted to compare the effects of the single, double, and 

 triple systems of training as to the season of maturity and total yield of fruit. 

 As an average for the three seasons the single-stem plants yielded highest, 

 with an average yield of 37.9 oz. of fruit per square foot bed area ; those with 

 double stems averaged 37.1 oz. per square foot, and those with triple stems 

 only 84.3 oz. per square foot. On an average for the three seasons' test the 

 single-stem plants outylelded the double-stem plants by 1.7 oz. and the triple- 

 stem plants by 4.2 oz. to the square foot of bed area, during the period of the 

 early harvest. During the period of midseason harvest the double-stem plants 

 outylelded the single-stem plants by 0.8 oz., and the triple stem by 0.4 oz. per 

 square foot bed surface. During the late harvest the triple-stem plants out- 

 yielded the single and double stem plants by 0.2 and 0.1 oz., respectively. These 

 results indicate that increasing the number of stems per plant decreases early 

 production of fruit to some extent. Individual fruits from single-stem plants 

 averaged 0.3 oz. heavier than those of the double-stem plants, and 0.2 oz. heavier 

 than those of the triple-stem plants. The test, as a whole, indicates that the 

 single-stem system of training has proved slightly superior in earlluess, in total 

 yield, and In convenience and simplicity of handling. 



