Relationship Between Plant Height And GA Metabolism Of A Wheat Mutant Dms

Wheat mutant dms is a mutant from Zhoumai 18 characterized as dwarf,male sterile and muti-pistils.There were three typical phenotypes in the progeny of dms: tall(T),semi-dwarf(M)and dwarf(D),the plant height of which are 30 cm,60cm,80 cm,respectly.In order to explore the relationship between stem development and gibberellin metabolism,GA content in the upper internodes of dms were determined by HPLC,the plant heights were measured after application of exogenous GA3 in field;the length of coleoptiles and the first leaves were measured after application of exogenous GA3 on the seeds of dms mutant and Zhoumai18 in lab.The results are as follows:1.The sensitive period and concentration of D,M and T plants to GA3 were different.In general,the GA3 sensibility of D,M and T plants were T > M > D.2.The lengths of the first leaves of Zhoumai18 and T plants increased significantly after application of 200 ?mol/L GA3,whereas this did not happen on M plant at any GA3 concentration.The coleoptile length of Zhoumai 18 increased significantly after application of100 ?mol/L GA3,however,those of T and M plants did not increase to significant levels at any GA3 concentrations.The data of D plants were failed to get due to low seed vigour and abnormal development,which might be the consequence of poor GA3 sensibility.3.dms mutant cannot be simply categorized as a GA biosynthesis deficient mutant or a GA insensitive one.The GA3 content in the upper internode of dms mutant fluctuated.Combined with the field experiment,it showed that the time when D plant was sensitive to exogenous GA3 was exactly the period when its GA3 content dropped to the lowest,whereas when D plant had a higher GA3 concentration,it became insensitive to exogenous GA3.