Expression and Stability Studies on Axillary Branching in Novel Grain Sorghum (Sorghum bicolor L.) Somaclonal Mutant, SbABM

Abstract

Sorghum bicolor axillary branched mutant (SbABM) is the fi rst axillary branched mutant reported in grain sorghum till date with desirable phenotype and stability of expression of axillary branching over generations. However, the trait was expressed at different levels of intensity (for number of axillary branches per plant) within the progenies of a single true breeding plant. The mutant along with its parent A-1 and a local check M 35-1 were analysed in variable environments like variation in plant density and intensive management practices over years to understand the stability and expression of axillary branching. The mutant exhibited signifi cant increase in yield which was in turn attributed to signifi cant increase in yield attributing parameters viz., number of branches per plant, number of panicles per plant, panicle weight per plant and thousand seed weight compared to A-1 and M 35-1 in all the three spacings and at two fertilizer levels. However, the expression of the traits in SbABM under different treatments was at par with each other. Though there was some variation in the degree of expression of characters in SbABM, the expression of the characters was highly stable, genetically controlled and signifi cantly superior over the other two rabi varieties.