AGRONOMIC CHARACTERISTICS IN MAIZE-TEOSINTE BACKCROSSES

Abstract

Teosinte populations (Zea spp.) could be important genetic resources to broad genetic diversity in maize (Zea mays L.) breeding programs, as well as to increase grain yield and improve some important agronomic traits in maize elite lines, when teosinte genes are transferred by backcrossing. The objective of this research was to evaluate changes in grain yield and agronomic traits of six recovered maize elite lines as a function of teosinte population and backcross level. The original lines and their backcrosses were evaluated in yield trials in Celaya, Guanajuato (1996 and 1997), and Tlajomulco, Jalisco (1996), in México. The experimental design used was a randomized complete block, and treatments were in split-split-plot arrangement; main plots were lines, teosinte populations were subplots, and backcross levels were the sub-subplots. Results showed that teosinte populations are an important source of alleles which could be used in maize breeding programs. Genes transference from teosinte to maize elite lines increased grain yield, plant vigor, and earliness. The best sources to increase grain yield were from Zea mays ssp. parviglumis Iltis & Doebley. The best sources to transfer earliness were from Zea mays ssp. mexicana (Schrader) Iltis. The best teosinte dosage was 6.25 %, because recovered lines had higher grain yield, plant vigor, and earliness than the original lines; nonetheless, the recovered lines had similar root and stalk lodging means to the originals.