TOMATO 295 
“7? When well supplied with water plants on a sandy loam have 
developed less disease than those on a clay loam. 
“8. Raising the soil temperature of greenhouse plants has in- 
creased the disease. 
“9. The writer is of the opinion that the increase in the disease 
from heavy watering is due to the development of harmful humic 
and ammonium compeunds and an accompanying decrease in ni- 
trates. 
“10. Susceptible tissue has more starch and more oil than normal 
tissue and its cell sap has a higher osmotic value. 
“11. The protoplasm in the cells from the fruit of the heavily 
watered plants is more granular and contains more oil than that 
of the lightly watered ones.” 
Fig. 94.—A convenient picking basket. 
Leaf spot or leaf blight (Septoria Lycopersici Speg.) 
sometimes attacks greenhouse tomatoes. It appears on 
the leaves as numerous oval or circular spots. The in- 
terior of the spots is light in color while the margins are 
dark. Bordeaux mixture is recommended for the control 
of this disease. 
Alternavia solani (E and M) J and G, is another form 
of blight which is sometimes encountered in the culture 
