Genetic control of cereal kernel texture: Towards a maize model

Because cereal kernel texture is a determinant of maize end-use properties, it is desirable to elucidate the genetic control of kernel formation and thereby to optimize maize kernel texture for breeding. Basically, maize kernel texture is determined by the ratio of vitreous endosperm in the peripheral region to the floury endosperm in the center of the kernel. In contrast to the puroindoline proteins (Pins) as the major determinants of grain texture specific to wheat, maize kernel texture is a quantitative trait that is controlled by many minor-effect genes. Nonetheless, substantial progresses have been made in unravelling gene regulatory networks underlying maize kernel formation that is related to its texture. Here, we review the current knowledge on maize endosperm development, focusing on vitreous and floury endosperm formation, and summarize the potential transcription regulatory mechanisms for starch and zein biosynthesis. The integration of the information will potentially provide valuable candidate genes for breeding maize varieties with improved kernel texture and quality.