An efficient sorghum transformation system using embryogenic calli derived from mature seeds.

Lihua Wang,Li Gao,Jieqin Li,Yanlong Liu,Ruirui Meng,Guoquan Liu

doi:10.7717/peerj.11849

Abstract

Significant progress has been made on sorghum transformation in the last decades; however, the transformation process has been constrained by the availability of immature embryos because most of the researchers have utilized immature embryos as favorable explants. Although immature embryos have been proven to be optimal for tissue culture and transformation, isolation of immature embryos is time-consuming, labor-intensive, and limited by warm weather. In this study, we developed an efficient genetic transformation system using mature seeds as explants. The nptII and gus gene, used as the selective marker and report gene respectively, have been co-transformed by particle bombardment. After optimization of tissue culture, the G418 concentration, and transgenic, the average transformation frequency at 13.33% was achieved routinely. The transgenic events and transgene copy numbers were determined by PCR and RT-PCR, respectively. The geneticin selection and GUS staining on T1 seedlings confirmed that the transgenic plants were heritable. Our results demonstrated that the efficient sorghum transformation system has been established using mature seeds as explants. This transformation system will promote sorghum research on genetic engineering and genome editing without seasonal weather conditions restriction and explant resources restriction.

Highlights

Sorghum (Sorghum bicolor) is the fifth most cultivated cereal crops in the world
With the availability of sorghum genome sequencing, more and more researchers have focused on the manipulation of gene function in sorghum because sorghum has the smallest genome size of the agronomically important C4 crops, and further, sorghum has been studied for its use as a C4 model crop (Paterson et al, 2009; Mace et al, 2013)
An efficient sorghum transformation system using embryogenic calli derived from mature seeds

Summary

Introduction

Sorghum (Sorghum bicolor) is the fifth most cultivated cereal crops in the world. It is a multipurpose crop that can be used as food, forage, biofuel, and industrial materials (De Morais Cardoso et al, 2017; Dahlberg, 2019). In Africa and parts of Asia, sorghum is used as a staple food (Adebo, 2020). With the availability of sorghum genome sequencing, more and more researchers have focused on the manipulation of gene function in sorghum because sorghum has the smallest genome size of the agronomically important C4 crops, and further, sorghum has been studied for its use as a C4 model crop (Paterson et al, 2009; Mace et al, 2013). An efficient sorghum transformation system using embryogenic calli derived from mature seeds.

Methods

Results

Conclusion