高粱株高调控基因qHT7.1与Dw基因的协同效应及育种应用OA

Sorghum plant height,exhibits a typical multi-gene control characteristic as a crucial agronomic trait.Exploring more novel height-associated genes is critical for breeding semi-dwarf and lodging-resistant va-rieties suitable for mechanized harvesting,and tall bioenergy/forage varieties with high biomass.The cloned dwarfing genes dw1,dw2 and dw3 primarily reduce plant height by shortening the lower internodes while maintaining the total number of internodes.Recent research has identified a novel plant height regulatory gene qHT7.1,which demonstrates a unique phenotype.The recessive allele qht7.1 significantly reduces the lengths of peduncle and the internodes below the flag leaf without altering the total number of internodes.Based on the literature reports,we analyzed the gene and protein sequences of qHT7.1,investigated the distribution of qHT7.1 alleles in different germplasm resources,and dissect the combined effects of qHT7.1 and Dw alleles for sorghum plant height.Due to the insertion of a 740bp transpoon in the second intron of the qHT7.1 gene,caused error splicing in coding sequence,generated a novel transcript qht7.1 containing an additional exon and premature termination codon.This mutation led to substantial alteration in the C-terminal protein sequence and loss of protein function,resulted in plant dwarfing.After detection the qHT7.1 alleles in different germ-plasm resources,we found that only the dominant allele qHT7.1 was detected in wild sorghums and Chinese landraces,while both the dominant allele qHT7.1 and the recessive allele qht7.1 were detected in African landraces,Indian landraces and Chinese elite parental lines,but the proportion of the recessive allele qht7.1 was relatively lower.Although different germplasm resources contain identical Dw1,Dw2,Dw3 and qHT7.1 alleles,the plant heights are still significant.These findings suggest that there must be other novel genes regu-lating the sorghum plant height.