부산대학교 도서관

The reduced height(Rht‐1) genes in wheat (Triticum aestivumL.) are integral in controlling plant height. Previous studies in other plant species have demonstrated that loss‐of‐function mutations in their orthologous Rht‐1genes results in plants with a slender phenotype illustrated by increased plant heights, sterility, and a constitutive gibberellic acid (GA3) response; however, this phenotype has not been described in wheat. In this study, nonsense alleles occurring in the GRAS domain of Rht‐A1, B1, and D1were combined to create single, double, and triple Rht‐1mutants. Homozygous lines possessing none, one, two, or three Rht‐1stop mutations were grown in replicated field trials in three environments to assess agronomic traits. Germination tests to measure GA3 responsiveness and gene expression analysis via RNA‐seq were also performed. Rht‐1triple mutants exhibited a slender phenotype characterized by rapid growth, elongated coleoptiles and internodes, elongated spikes, decreased tiller and spikelet number, and sterile heads. The presence of a single functional Rht‐1gene resulted in a normal phenotype. Differences in plant height among the Rht‐1double mutants, Rht‐1single mutants, and Rht‐1all wild‐type dosages trended toward increased plant height with increased Rht‐1stop mutation dosage. Differences in Rht‐1homeolog gene expression did not equate to differences in plant height between the different Rht‐1stop mutations. Nonsense alleles occurring in the GRAS domain of Rht‐A1, B1, and D1were combined to create single, double, and triple Rht‐1mutants.Rht‐1triple mutants exhibited a slender phenotype exhibited by rapid growth, elongated coleoptiles, and internodes.At least one functional copy of a Rht‐1gene was necessary to restore normal plant development.Differences in plant height among the Rht‐1double mutants, Rht‐1single mutants, and Rht‐1all wild‐type dosages trended toward increased plant height with increased Rht‐1 stop mutation dosage.Differences in Rht‐1homeolog gene expression did not equate to differences in plant height between the different Rht‐1stop mutations.