Transcriptomic Profiling of Shoot Apical Meristem Aberrations in the Multi-Main-Stem Mutant (ms) of Brassica napus L.

Rapeseed (Brassica napus L.) is a globally important oilseed crop with various uses, including the consumption of its succulent stems as a seasonal vegetable, but its uniaxial branching habit limits the stem yield. Therefore, developing a multi-stem rapeseed variety has become increasingly crucial. In this study, a natural mutant of the wild type (ZY511, Zhongyou511) with stable inheritance of the multi-stem trait (ms) was obtained, and it showed abnormal shoot apical meristem (SAM) development and an increased main stem number compared to the WT. Histological and scanning electron microscopy analyses revealed multiple SAMs in the ms mutant, whereas only a single SAM was found in the WT. Transcriptome analyses showed significant alterations in the expression of genes involved in cytokinin (CK) biosynthesis and metabolism pathways in the ms mutant. These findings provide insight into the mechanism of multi-main-stem formation in Brassica napus L. and lay a theoretical foundation for breeding multi-main-stem rapeseed vegetable varieties.

Automated summary

A stable mutant of rapeseed with the multi-stem trait was discovered, showing abnormal shoot apical meristem development and increased main stem number compared to the wild type. Histological and scanning electron microscopy analysis revealed multiple shoot apical meristems in the mutant, while only one was found in the wild type. Transcriptome analysis showed significant changes in gene expression involved in cytokinin biosynthesis and metabolism pathways in the mutant. These findings provide insights into the mechanism of multi-main-stem formation in Brassica napus L. and establish a theoretical foundation for breeding multi-main-stem rapeseed vegetable varieties.