Inheritance of Resistance to Downy Mildew Disease in Maize

Abstract

This study was carried out in the disease nursery at Agricultural Research Station of Sakha during 2014 and 2015 maize growing seasons. Theinheritance of resistance to sorghum downy mildew disease in maize was investigated. The obtained results indicated that, the additive gene effect, additive by additive and additive by dominance gene effects in two tested maize single crosses (SC) were significant and generally were in the resistance direction (have negative sign). While thedominance and dominance bydominance gene effects were notsignificant in two tested maize genotypes. Therefore, recurrent or mass selection scheme using the advanced generations of two tested crosses (SC 10 and SC120) would be appropriate to accumulate genes for resistance to this disease. As well as, the degree ofdominance (patience ratio) for disease in the twotested crosses were in partial dominance and in direction of resistant parent (less than one and has negative sign). Moreover, the estimates of heritability in broad sense were high, while it was low in narrow sense and in the genetic advance in the tested maize crosses. It seems likely that the environmental variation play a serious role in development of this disease. Moreover, the cytoplasmicconstitution of the female parent are interfere in conditioning theinheritance of resistance to sorghum downy mildew disease in maizeespecially in case of the single cross 120.