Introgresion de fuentes de resistencia a roya comun y tizon foliar en lineas endocriadas de maiz (Zea mays L.)

This study was developed in the framework of the project PR-154 “Conservación y uso sostenible de los recursos fitogenéticos locales para la alimentación y la agricultura (RFAA) para contribuir a la seguridad alimentaria de los pequeños agricultores de Argentina” funded in the 4th  project cycle of Benefit Sharing Fund (BSF) of the International Treaty on Plant Genetic Resources for Food and Agriculture (ITPGRFA) of the Food and Agriculture Organization (FAO) of the United Nations (UN).

The objective of this research was to quantify the potential of a group of local populations of maize as donors of favorable alleles for resistance to P. sorghi and E. turcicum, as well as to estimate the potential for resistance to P. sorghi and E. turcicum, as well as to estimate the ACG and ACE genetic components genetic components of ACG and ACE involved in the expression of this resistance from population×lineage hybrid combinations.

Maize (Zea mays L.) is one of the most important crops worldwide and is affected by several pathogens that put productivity and grain quality at risk. Common rust (Ppathogens  and northern corn leaf blight (Exserohilum turcicum) are among the most important diseases affecting maize at the Corn Belt region of Argentina. The aim of the present work was to characterize the potential of four maize landraces (ARZM05074, ARZM08096, ARZM13057 (resistant ones) and ARZM04044 (susceptible)) as donors of favorable alleles to improve disease resistance to both pathogens. In 2018/2019 landraces were crossed to three inbreed lines, used as a female parent (LP29 (resistant), LP221 (moderately resistant) and LP2542 (susceptible)). In 2019/2020 the G1 crosses (population×inbred), were evaluated under infection with P. sorghi and E. turcicum. A diallel analysis of G1 displayed important GCA values revealing that additive genetic effects were predominant for both traits. Indeed ARZM05074 stands out as potential donor of favorable alleles for disease resistance to P. sorghi and E. turcicum. The results presented here would help to broaden the genetic base of maize breeding programs and to achieve food security in a sustainable manner. Further research should be conducted in a broader environmental range.