关键词: 光形态建成, 玉米中胚轴, EMS突变体筛选, 植物激素

Abstract: The hypocotyls of dicotyledons and mesocotyls of monocotyledons are important morphological hallmarks for skotomorphogenesis and photomorphogenesis. Their elongation is promoted by darkness and their growth is inhibited by light illumination. It has been established that the morphogenesis of hypocotyls in the model species Arabidopsis was cooperatively regulated by genes in light signaling and also other plant hormone signaling pathways. The homologs of these genes in crop species have been implicated with multiple important agronomic traits. Based on these, an EMS-mutagenized maize population containing 6 150 lines in Zheng 58 background and 2 340 lines in B73 background was screened for mutants in skotomorphogenesis, with elongation dynamics of mesocotyls as the morphological marker. In total 96 mutants with abnormal lengths of mesocotyls were recovered. A further study on these 2 mutants indicated that they were defective in BR signaling. The identification and characterization of mutants in skotomorphogenesis is not only helpful for dissecting in depth the light signaling components in maize, but also revealed the interaction between light signaling and other signaling pathways.

Key words: photomorphogenesis, mesocotyl of maize, screening of EMS mutants, phytohormone