F. KiDD AND C. West 221 



done, although few in iminber, are of considerable interest because they 

 point to methods by means of which an action induced during germina- 

 tion may favourably or otherwise afi'ect the whole course of development. 



In many cases treatments of the seed previous to or during germina- 

 tion have been devised primarily with a view to seed-sterilisation and 

 fungus control or with a view to increasing the percentage of seeds able 

 to germinate. It has thus happened that observations on the physio- 

 logical behaviour of the plants produced from these treated seeds have 

 in most cases been incidental. This is vinfortunate because in many 

 cases an increase in the vigour and size of the seedlings has been noted, 

 and because there is considerable evidence to show that a very close 

 correlation exists between the size and vigour of the seedling, even in its 

 earliest stages, and the final yield of the adult plant. 



For instance, in the last report of the Experimental and Research 

 Station of the Nursery and Market Garden Industries Development 

 Society, Cheshunt, it is recorded as a result of a series of careful quanti- 

 tative experiments carried out by Mr F. G. Gregory (iG) that in the case 

 of cucumbers a correlation exists between the area of the cotyledons 

 and the dry weight of the plant after 30 days^, also betw^een the growth 

 rate of the main stem and laterals and the weight of fruit produced in 

 the first two "flushes." It is obvious that such observations are of 

 great importance to horticulturists since they enable the practical man 

 to forecast the future efficiency of a plant from the seedling stage. 



On the one hand recent work is tending to establish that the ordinary 

 variations observed in the size and vigour of seedlings are reflected in 

 the size of the final yield independently of the environmental conditions 

 obtaining throughout the main period of the plant's life. On the other 

 hand it is known that a large number of easily applicable, brief treatments 

 of seeds previous to and during germination, favourably affect the size 

 and vigour of the seedlings produced. But practically no attempt has 

 hitherto been made to bring these two facts together and to discover 

 whether increased size and vigour of seedlings due to seed-treatments 

 will pre-determine an increase in the size of the final yield independently 

 of the conditions obtaining during the main period of growth, in other 

 words, whether increased yields can be obtained as the result of simple 



^ The authors are indebted to Mr Gregory for p3rmi>;sion to make use of the following 

 unpubhshed data: — - 



For correlation between (i) Maximum area of the cotyledons | _ 



(ii) Dry weight of the entire plant after 30 daysf 

 For correlation between (i^ Maximum area of the cotyledons 1 _ ^ , 



(ii) Maximum area of the first foliage leaf J 



Ann. Biol, v 15 



