The Bulletin. 51 



tobatfo lias boon ki'o^vii juM-sistently in ono section and under a ((M-tain set 

 of environments lor a long period of time, it lias tended lo adapt itself to tlif>.se 

 conditions, and becomes better suited in constitution and character to that 

 section. 



Other things being equal, therefore, a strain of seeds that has been de- 

 veloped in any section ought to be better for that section than seeds bi-ought 

 in from some distant place, where the environing conditions are materially dif- 

 ferent. If a strain seems to run out after being in a certain sectiDU for a 

 long period of years, it is quite likely to be due to lack of intelligent and care- 

 ful methods of seed selection and saving, rather than to any inherent in- 

 feriority in the strain itself. 



The principles thus far mentioned are very simple and such as any farmer 

 can easily carrv out, with but little expense and loss of time. To sum them 

 up briefly, they are: Use only heavy, mature seed; save it under bag to pre- 

 vent running out by cross-fertilization with inferior plants; and, as a gen- 

 eral rule. sliCk to varieties developed in your own neighborhood, rather than 

 those from distant conununities, where conditions are somewhat different. 

 These methods will undoubtedly maintain in full the sujierior points of any 

 strain of seed, and there will be in most cases an improvement even, if suf- 

 ficient care is taken to save seeds always from the most superior plants that 

 are produced. 



METHODS OF IMPROVING THE TYPE. 



It is to be expected, perhaps, that the main steps forward in improving 

 plants can best be taken by trained specialists, who are in a position to make 

 a careful study of the subject over a very wide field, and who can devote 

 their time to it persistently and in a systematic manner for the necessary 

 period of several years. 



In working for the improvement of crops by breeding methods, the prospects 

 for ultimate success are based upon the recognition of the principle of in- 

 dividuality and of variability among plants. It is the key to the situation, 

 and in it is found the breeder's opportunity. Is it not a most reasonable 

 proposition to suppose that each plant has its own individual peculiarities, 

 independent of the circumstances in which it is placed, in very much the 

 same way that animals have their individual peculiarities? One plant may 

 naturally have a stronger digestive or assimilative power than its neighbor, 

 and will", therefore, under exactly the same conditions of soil fertility, climate, 

 etc., make a larger growth. Another plant might differ in the number of 

 leaves it would naturally bear; yet another would dilfer, perhaps, in the 

 shape, size, venation, thickness or other quality of the individual leaves; 

 another in the distance from one leaf to tlie next on the stalk ;-that is, in the 

 length of the iuteruodes, again there may be an occasional plant here and 

 there that, by reason of some constitutional vigor or structvu-al modification, 

 may olfer a much greater resistance to the attacks of rust, blight, wilts, or 

 other diseases than its neighbor, and would thus offer an opportunity of 

 breeding up from it, by inheritance and selection, a race of plants that 

 would be proof against one or more of these diseases. Either of these indi- 

 vidual plants may also differ markedly in its power to transmit and per- 

 petuate its own peculiarities. This last is a very important fact to be taken 

 into consideration by those engaged in the systematic improvement of the 

 species. It is here that we see the origin of the idea of "blood lines," of 

 such generally recognized importance in animal breeding — prepotency, as the 

 animal-breeders call it. Any of these individual peculiarities may be seized 

 upon by the plant-breeder as a starting poiut for the improvement of the 

 type. 



IMPROVEMENT B\' BREEDING. 



There are, broadly speaking, two general methods of procedure in improv- 

 ing plants — the method of hybridization, or cross-breeding, and the method of 

 straight selection. 



By the method of hybridization the flower of the mother plant — that is, 

 of the plant selected to produce the seed — is artificiallj'' impregnated with 

 pollen from the plant selected as the male parent, all other pollen lieihg 

 carefully excluded. To prevent self-pollination, the flower is emasculated; 



