TEOSINTE IN MEXICO' 



The closest wild relative of Maize is Teosinte — a forage plant hitherto known only 



as an annual. A perennial form discovered in Southern Mexico 



should prove of value to the breeder 



G. N. Collins 

 Bureau of Plant Industry, U. S. Department of Agriculture 



TEOSINTE is the Mexican name 

 of a genus of large grasses (Euch- 

 laena), the only wild plant that 

 has been hybridized with maize. As 

 at present recognized Euchlaena is con- 

 sidered a monotypic genus, all forms 

 of teosinte being referred to the one 

 species, Euchlaena Mexicana Schrad. 



Before our recent trip to Mexico we 

 were familiar with but two forms of 

 teosinte; first, the teosinte listed by 

 many American seed firms and widely 

 grown in warm countries as a forage 

 plant. In the United States it matures 

 seed only in southern Florida and all 

 the American trade is supplied with 

 seed from a single plantation. 



The origin of this type is uncertain. 

 The Florida form appears to be the 

 same as that distributed from France to 

 many tropical countries, and the early 

 records indicate that teosinte was in- 

 troduced into France from Guatemala. 



The form and color of the seed, as 

 well as a number of plant characters, 

 make it an easy matter to separate 

 this variety, which we have called 

 "Florida," from the second form known 

 as "Durango," from its place of origin 

 in the Mexican state of Durango. 



The Durango variety was first 

 brought to the United States by Dr. 

 Edward Palmer, the veteran Mexican 

 collector. The original introduction 

 failed to mature seed when planted 

 at Washington and the stock was lost. 



A second lot of seed of the Durango 

 variety was obtained from Dr. H. V. 

 Jackson of Durango. Planted in south- 

 ern California it produces an abun- 

 dance of seed. So far as known Du- 

 rango teosinte has not been exploited 

 commercially, except that it was the 

 form from which Burba nk derived the 



variety called "Early Harvest." Dr. 

 Jackson supplied Mr. Burbank with 

 seed of Durango teosinte and in fact 

 sent seed of hybrids between this and 

 maize that may have provided the 

 intermediate forms put forth by Mr. 

 Burbank as demonstrating the evolu- 

 tion of maize from teosinte. 



The Durango variety is distinctly 

 more maizelike than "Florida," and the 

 possibility that the distinguishing char- 

 acteristics of this form might be due to 

 admixture with maize at some remote 

 time made it seem unwise to recognize 

 the two forms as specifically distinct 

 until a study could be made of the 

 conditions under which they grow in a 

 wild state. 



Before 1910 teosinte was known only 

 as an annual plant. In that year Dr. 

 A. S. Hitchcock discovered in the 

 State of Jalisco a perennial form of 

 teosinte that propagates itself by 

 rhizomes. All the annual types of teo- 

 sinte were known to hybridize readily 

 with maize and it was at once appre- 

 ciated that new forms, of possible 

 economic as well as of great scientific 

 interest, would result if living plants 

 of this perennial type could be obtained 

 and if crosses with maize could be 

 affected. 



The unsettled conditions in Mexico 

 made it impracticable to conduct ex- 

 plorations in that country until the 

 past season. In vSeptember and Octo- 

 ber 1921, Mr. J. H. Kempton and the 

 writer visited Mexico primarily for 

 the purpose of procuring living plants 

 and seeds of the perennial form and 

 also to obtain more definite informa- 

 tion regarding the distribution and 

 uses of the annual types of teosinte 

 growing in Mexico. 



^ Paper read before the Botanical Society of America, Toronto, Canada, December 28, 1921. 



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