POWER TO IMPRESS CHARACTERISTICS 23 



If the survival of the like were an absolute law there would be 

 no possibility of change and all our plants would be alike. The 

 environments of the plants set up variations and we may find that 

 plants which are unlike are descendants from the same parents. 

 These various forms may suit the different environments into which 

 they may fall and the result is a survival of the unlike. Take the 

 muscadine grape, for example. We find in nature numerous varie- 

 ties, all apparently traceable to the same common parentage. By 

 the aid of men, the varieties found among all garden and orchard 

 plants are greatly improved and their characteristics fixed more 

 firmly. 



Extreme or Sudden Variation. — Mutation is a name given to 

 any extreme or sudden variation from a type which we have been 

 growing. The term "sports" is sometimes applied to these sudden 

 variations. It is fairly well established by De Vries and others 

 that the characteristics shown by mutations may be inherited by 

 their offspring. Thus new extremely different varieties may be 

 established somewhat quickly. 



Reversion. — Any tendency of the plants of a new generation 

 to assume forms differing from their parents, but resembling gener- 

 ations farther back, is called reversion. If variations are estab- 

 lished by propagating mutants, or those with sudden variations, it 

 is common to notice certain individuals in the line reverting to 

 the old type from which the sudden variation sprang. The plant 

 breeder may find it necessary to throw out all individuals showing 

 this tendency to revert to the old forms. He must keep clearly in 

 mind his ideal and select those individuals which show a strong 

 tendency in that direction. 



Influence of Soil and Surroundings. — The environment of 

 plants has a strong influence upon their manifest characteristics. 

 When the plant breeder is making his selection, he must note care- 

 fully the surrounding influences. Plants adapt themselves to their 

 surroundings. Plants of the same origin grown in different soils 

 may show very different results. Fertilizer and tillage should be 

 uniform in all plant breeding plots. 



It is believed by many scientists that the differences due to 

 surroundings may be inherited by the offspring. The practices of 

 some plant breeders are based upon this belief. 



Power to Impress Characteristics. — Prepotency is the term 

 given to the power of plants to project or impress their own char- 

 acters upon their offspring. Some individuals fail to mark their 



