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"DAMPING OFF" AND "FOOT ROT" 

 OF TOMATO SEEDLINGS 



By W. F. BEWLEY, 



Experimental and Research Station, Cheshunt. 



"Damping off" is a term commonly used by nurserymen to describe 

 the death of very young seedlings. In the seed-boxes, the young seedlings 

 are attacked at the base, and the rapid collapse of the stem tissues at 

 this point causes the seedlings to fall over. 



"Foot Rot" is the term applied when the young plants are attacked 

 at a later date. In this case the seedlings grow strongly in the seed-boxes, 

 but are attacked after "potting up" or even after "planting out" in 

 the houses. As in the case of "damping off," the base of the stem is 

 attacked, and these tissues collapse causing the plant to fall over. 



Generally the highest death rate has occurred after periods of 

 watering, and this has led growers to draw a close connection between 

 the disease and damping, and has given rise to the name "damping off." 

 Properly speaking, the term applies to a fatal disease set up through the 

 agency of parasitic fungi, but it is often made to embrace the wilting 

 of seedlings caused by some injurious chemical or physical factor in 

 the soil. These latter causes of death are of somewhat rare occurrence, 

 and when they do take place may usually be traced to carelessness on 

 the part of the workman. 



Cresylic acid, which is extensively used in the winter for sterilising 

 the wood- work, staging and soil itself in the glass houses, has occasionally 

 been known to produce a wilt of young plants, when the proper pre- 

 cautions necessary in such sterilisation have been disregarded. In one 

 instance, an insufficient time had elapsed between sterilising the pro- 

 pagating benches and the raising of seedlings upon them. The result 

 was that the seedlings were stunted in growth and turned a blue-green 

 colour; many were so scorched in the stem that they fell over and had 

 all the appearances of "damped off" seedlings. 



In another instance a quantity of undiluted cresylic acid had been 

 upset in one part of a house by a workman, who omitted to report the 

 accident. In due course the house was planted, and, while the greater 



