Robust soybean leaf agroinfiltration

Area of Science:

• Plant Biotechnology
• Molecular Biology
• Crop Science

Background:

• Agrobacterium-mediated agroinfiltration is a key transient assay in dicot species like Nicotiana benthamiana.
• Testing gene constructs directly in crop species is desirable for agricultural biotechnology.
• Soybean (Glycine max) is a globally significant dicot crop, necessitating efficient gene expression tools.

Purpose of the Study:

• To develop a robust agroinfiltration method for transient gene expression in soybean leaves.
• To identify critical parameters influencing the success of agroinfiltration in Glycine max.
• To provide a new research tool for soybean biotechnology and synthetic biology.

Main Methods:

• Optimization of Agrobacterium culture conditions and expression vectors.
• Use of Silwet L-77 surfactant and vacuum infiltration (5 min at -85 kPa).
• Selection of fully expanded leaves at the VC or V1 growth stage, followed by dark incubation.

Main Results:

• Successful high-level expression of GUS, fluorescent proteins, and the RUBY reporter (betalain) in soybean leaves.
• Identification of key factors for successful soybean agroinfiltration: genotype, surfactant, developmental stage, and Agrobacterium conditions.
• Demonstration of the method's efficacy in two soybean lines (V17-0799DT and TN16-5004).

Conclusions:

• A reliable agroinfiltration protocol for soybean leaf transient gene expression has been established.
• Plant genotype, leaf age, surfactant, and Agrobacterium parameters are crucial for successful agroinfiltration.
• Leaf developmental stage is speculated to be the most critical factor for optimizing agroinfiltration in crop species.