J01N£ OF AGRIOmm RESEARCH 



Voiv. XII Washington, D. C, February 4, 1918 No. 5 



NEW-PLACE EFFECT IN MAIZE 



By G. N. Collins, Botanist, Office of Acclimatization and Adaptation of Crop Plant? and 

 Cotton Breeding, Bureau of Plant Industry, United States Department of Agriculture 



INTRODUCTION 



Widely divergent opinions have been expressed regarding the ad- 

 visability of transferring seed from one region to another. With maize 

 (Zea mays) the transfer of seed is generally held to be disadvantageous. 

 Numerous experiments have shown that when seed of the same original 

 variety, but grown at two places, is planted side by side at one of the 

 places the results are in favor of the local seed. 



The relative superiority of the locally selected seed has been so pro- 

 nounced that the securing of seed from distant localities, except where 

 grown for forage, has been discouraged. The natural result is to confine 

 the utilization of carefully selected strains to the localities where the 

 breeding is done. Caution in transferring seed is certainly desirable, but 

 the results of the experiments here reported indicate that two opposing 

 factors are involved, the relative importance of which must be determined 

 before generalizations are made. 



The differences shown between the geographically separated lines of 

 the same variety when brought together in the locality where one of the 

 lines has been grown may be ascribed to three general causes: 



(i) Cross-pollination. Varieties removed to different localities may 

 become crossed with other sorts, with the result that their character- 

 istics are changed in a greater or less degree. 



(2) Different standards of selections. Changed conditions in con- 

 nection with the diversity that exists in all varieties bring slightly different 

 types of plants into prominence, and selection, either conscious or un- 

 conscious, results in a changed type. 



(3) New-place effects. The more or less temporary changes that fol- 

 low a transfer to new conditions, caused by the novelty or "shock" of the 

 new environment without special reference to the nature of the change. 



So far as known, new-place effect, which the experiments here re- 

 ported show to be a significant factor in the transfer of seed, has not 

 previously been considered with regard to maize. 



Journal of Agricultural Research, Vol. XII, No. s 



Washington, D. C. Feb. 4, 1918 



lu Key No. G— 134 



(231) 



