Comparative Cytological and Transcriptome Analyses of Anther Development in Nsa Cytoplasmic Male Sterile (1258A) and Maintainer Lines in Brassica napus Produced by Distant Hybridization.

Man Xing,Mei Guan,Chunyun Guan

doi:10.3390/ijms23042004

Man Xing, Mei Guan + Show 1 more

Open Access

https://doi.org/10.3390/ijms23042004

Copy DOI

Abstract

1258A is a new line of B.napus with Nsa cytoplasmic male sterility (CMS) with potential applications in hybrid rapeseed breeding. Sterile cytoplasm was obtained from XinJiang Sinapis arvensis through distant hybridization and then backcrossed with 1258B for many generations. However, the characteristics and molecular mechanisms underlying pollen abortion in this sterile line are poorly understood. In this study, a cytological analysis revealed normal microsporogenesis and uninucleate pollen grain formation. Pollen abortion was due to non-programmed cell death in the tapetum and the inability of microspores to develop into mature pollen grains. Sucrose, soluble sugar, and adenosine triphosphate (ATP) contents during microspore development were lower than those of the maintainer line, along with an insufficient energy supply, reduced antioxidant enzyme activity, and substantial malondialdehyde (MDA) accumulation in the anthers. Transcriptome analysis revealed that genes involved in secondary metabolite biosynthesis, glutathione metabolism, phenylpropane biosynthesis, cyanoamino acid metabolism, starch and sucrose metabolism, and glycerolipid metabolism may contribute to pollen abortion. The down regulation of nine cytochrome P450 monooxygenases genes were closely associated with pollen abortion. These results suggest that pollen abortion in 1258A CMS stems from abnormalities in the chorioallantoic membranes, energy deficiencies, and dysfunctional antioxidant systems in the anthers. Our results provide insight into the molecular mechanism underlying pollen abortion in Nsa CMS and provide a theoretical basis for better heterosis utilization in B.napus.

Highlights

Introduction published maps and institutional affilCytoplasmic male sterility (CMS) prevents self-pollination through pollen abortion
There were no significant differences in stamen size and shape between the sterile line triangular, fleshy, and pollen-free, while the pollen of the maintainer line was intact
We found that two peroxidase genes (LOC106369846 and LOC106376069) in sterile lines were up-regulated after pollen abortion (Figure 8A, Class V)

Summary

Introduction

Cytoplasmic male sterility (CMS) prevents self-pollination through pollen abortion. It is important for the utilization of crop heterosis, which has led to substantial improvements in crop growth and development as well as resistance to adverse conditions and disease, leading to substantial increases in crop yields. Heterosis is widely used in rice [2], maize [3], rape [4], sunflower [5], tomato [6], and other crops, and a large number of hybrid seeds are used in production. Brassica napus has strong heterosis, and three-line hybrids are widely used in production. There are many types of CMS in oilseed rape, which can be divided into three categories according to their iations

Methods

Results

Conclusion