802 EXPERIMENT STATION RECORD. 



chance is prominent enough in plant breeding at best. The breeding 

 work projected under this new fund has been given a definiteness of 

 i:)urpose. has been restricted to limits within which it could be care- 

 full}^ followed, and in a considerable number of instances has been so 

 planned as to contribute to a better understanding of the principles 

 of breeding. 



It is proposed, for example, to make thorough studies upon hered- 

 ity in plants, the variability in morphological characters in cultivated 

 wheat, the extent of hybridizing in nature and the environmental 

 conditions associated therewith, effects of external environmental fac- 

 tors upon hereditable morphological characters, and the correlation of 

 visible morphological characters with the presence and distribution 

 of such constituents as gliadin, glutenin, and starch in the grain. Corn 

 breeding for the semiarid region is being taken up from the standpoint 

 of the factors which constitute drought resistance as a basis for such 

 l,>reeding, and the development of immune or disease-resistant strains 

 of crops on the basis of studies upon what constitutes immunity in 

 different cases, and the principles underlying development of disease 

 resistance. These physiological studies will take up anatomical and 

 chemical phases of the subject, such questions as the functions of 

 tannin in the economy of the plant, its presence in pathological tissues, 

 effect on parasites, etc. 



In general, the pathology and physiology of disease is to be studied 

 in a more comprehensive way than heretofore, taking up such matters 

 as the relation between the character of the soil and certain diseases, 

 notably the rektion of marly soils and of lime to chlorosis of citrus 

 fruits, the specific influence of the different factors which go to make 

 up climate upon health and susceptibility to disease, and the relation 

 of nutrition to the latter. Naturally a quite large number of plant 

 diseases are to be made the subject of systematic study. In some 

 cases these are new or little understood diseases, and in others the 

 object is to clear up doubtful points as to the organisms inducing 

 them, their life cycle, relationships, susceptibility to various in- 

 fluences, means of dissemination, etc., as a more intelligent basis for 

 combating them. There is opportunity for much profitable work of 

 this kind, for in the pressure for results which should indicate reme- 

 dies to be applied it has often been impossible to go as deeply into the 

 nature and cause of the disease and the influences affecting it as is 

 clearly desirable. 



The same is true to a considerable extent in the case of economic 

 insects, and the use of sprays and other treatment. Now that the 

 opportunity is offered, it is found desirable to go back to some of 

 our most common insect pests and study more thoroughly certain 

 points in their habits and life histories, environmental conditions 

 which affect them, and similar matters, as bearing ultimately on 



