DIVISION OF VEGETABLE PHYSIOLOGY AND PATHOLOGY. 57 



heavier yield aud containing larger percentages of gluten can d<nibt- 

 less be ol)tained. Plans for cooperation with the experiment stations 

 of the West in this work are now under vrny. It is recognized that to 

 obtain varieties of the greatest value for the various districts the 

 varieties themselves must be developed under more or less local con- 

 ditions. This can probably be best effected through cooperation with 

 the stations, and to this end the cooperative work is l)eing planned. 

 It is recognized, for instance, that macaroni wheats can probably be 

 best developed in Texas, and that other wheats adapted to different 

 purposes can be obtained through work at other stations Avhere con- 

 ditions are different. The main object of the work as a whole is to 

 develop the general pi'inciples of l)reeding, leaving it to the stations 

 themselves to look to the details with respect to local needs. 



The investigations inaugurated in the improvement of citrous fruits 

 will be continued, but it will be several j^ears before the various 

 hybrids can be fruited sufficiently to determine their true worth. In 

 tlie meantime facts as regards hardiness and other desirable charac- 

 teristics will be constantly accumulating. The pineapples obtained 

 as a result of Iwbridization will be carefully studied, and such impor- 

 tant points as may develop in regard to their value will Ije recorded. 

 It is believed that there is a promising outlook in this country for the 

 cultivation of this crop, and it is verj' desirable to improve the varie- 

 ties now on hand, as it is recognized that but few of them have attained 

 a high state of cultivation. 



The work of improvement of grapes will be continued in California, 

 and as a number of the varieties are now beginning to fruit, plans are 

 being formulated for distributing them in a way that will show the 

 connection of the Department Avith the work and at the same time 

 give the best and widest distribution to the material oji hand. The 

 question of distributing the various improved forms of plants is an 

 important one, and is receiving careful attenti<jn. It would be mani- 

 festly unwise to permit a control of the plants which would in anj^ 

 way interfere with or curtail freedom of <listribution among the peo- 

 p\e. It is also important to carefully grow the productions until their 

 full value is thoroughly ascertained. 



In connection with the plant-breeding, work, careful attention is 

 being given to the underh'ing iDrinciples of the subject. Cooperative 

 experiments with several experiment stations have been inaugurated 

 to test the effect of environment on plants, and to determine how this 

 effect can l^e best utilized by the practical plant breeder. Experi- 

 ments for the fixation of hybrids into stal)le races are also under way, 

 and some points of interest have been obtained. This ijarticular line 

 of work is of such wide application and must be carried on under such 

 varj'ing conditions of climate and soil that it will probably be brought 

 to a successful issue better by the Dei)artnient than by the experiment 

 stations, and it will enable the Dej)artment'to i^lace in the hands of a 

 number of plant breeders information as to the principles underlying 

 the work. 



The tobacco investigations are being continued in cooperation with 

 the Division of Soils. The princij)al lines of work planned have for 

 their object the obtaining of further information in regard to the 

 changes taking place in the tobacco leaf during fermentation, and, 

 furthermore, to determine if possible the cause of the aromas of the 

 various types of tobacco. These questions being Avorked out, it may . 

 be i30s.sible to determine definitely whether or not conditions of growth 

 and of handling can be so changed as to bring about the desired effects 



