Morphological,Biochemical and Genetic Analysis of a Brittle Stalk Mutant of Maize Inserted by Mutator

摘要

cqvip:Mutants on stalk strength are essential materials for the studies on the formation of plant cell wall.In this study,a brittle stalk mutant of maize,designated as Bk-x,was screened from a Mutator inserted mutant library.At the germination and early seedling stage,the mutant plants were indistinguishable from the normal ones.However,all of the plant organs were brittle after the 5th-leaf stage and remained brittle throughout the rest of the growing period.Microstructure observation showed that the cell wall in vascular bundle sheath of Bk-x was thinner than that in normal plants.The leaf mechanical strength in Bk-x was 77.9% of that in normal plants growing at Xishuangbanna(BN),Yunnan province and that was 61.7% in Wuhan(WH),Hubei Province,China.The proportion of cellulose was 12.3% in Bk-x,which was significantly lower than that in normal plants(26.7%),while the soluble sugar content was 36.1% in Bk-x,which is significantly higher than that in normal plants(12.4%).Genetic analysis using two F 2 populations and one F 2:3 families demonstrated that the trait of brittle stalk is controlled by a single recessive gene.