Breeding Maize Hybrids with Improved Drought Tolerance Using Genetic Transformation

Area of Science:

• Agricultural Science
• Plant Biotechnology
• Genetics

Background:

• Drought poses a significant threat to global crop productivity, necessitating strategies for enhanced crop resilience.
• Genetic manipulation offers a promising avenue for developing drought-tolerant crop varieties, particularly for essential crops like maize.

Purpose of the Study:

• To develop drought-tolerant maize by introducing the Escherichia coli betA gene into elite inbred lines.
• To evaluate the efficacy of the betA transgene in improving drought tolerance and yield in maize under field conditions.

Main Methods:

• Transformation of elite maize inbred lines (DH4866, Qi319, Y478, DH9938) with the Escherichia coli betA gene using Agrobacterium.
• Evaluation of drought tolerance in T4 transgenic progenies and hybrids under reduced irrigation in field trials.
• Measurement of glycine betaine levels and assessment of tolerance at germination and seedling stages.

Main Results:

• Transgenic maize lines exhibited significantly enhanced drought tolerance compared to non-transformed controls.
• Accumulation of higher glycine betaine levels was observed in transgenic plants.
• Transgenic hybrids demonstrated improved drought tolerance and higher grain yield under drought stress conditions.
• The betA transgene conferred improved crop viability in varying soil moisture conditions.

Conclusions:

• The Escherichia coli betA gene effectively enhances drought tolerance and yield in maize.
• Transgenic maize lines and hybrids show potential for cultivation in arid and semi-arid regions.
• Genetic engineering using the betA transgene is a viable strategy for improving crop resilience to drought stress.