Field performance of transgenic sugarcane produced using Agrobacterium and biolistics methods

Area of Science:

• Agricultural Science
• Plant Biotechnology
• Genetics

Background:

• Genetic improvement of sugarcane is crucial for developing high-yielding cultivars with enhanced traits like herbicide and insect resistance.
• Successful genetic modification relies on producing transgenic plants that maintain or improve field performance.

Purpose of the Study:

• To assess the field performance of transgenic sugarcane plants generated through Agrobacterium-mediated (Agro) and biolistic (Biol) transformation methods over three years.
• To compare the yield, ratoonability, and sugar quality of transgenic sugarcane with the parent clone and untransformed tissue culture controls.

Main Methods:

• Agrobacterium-mediated (Agro) and biolistic (Biol) transformation methods were used to generate transgenic sugarcane events.
• Field trials were conducted over three crop cycles (plant, first ratoon, second ratoon) to evaluate growth and yield.
• DNA fingerprinting techniques were employed to detect genetic changes.

Main Results:

• While a combined analysis showed reduced growth and yield in both Agro, Biol, and tissue culture (TC) events compared to the parent clone (PC), individual event analysis revealed that some transgenic events from both methods achieved comparable yields to PC.
• Biolistic transformation resulted in a greater percentage of transformants with growth and yield similar to the PC compared to Agrobacterium-mediated transformation.
• Crop ratoonability, sugar yield components (Brix%, Pol%, CCS), transgene expression stability, and transgene copy number were largely unaffected by transformation or tissue culture.

Conclusions:

• Both Agrobacterium-mediated and biolistic transformation methods are capable of producing commercially suitable transgenic sugarcane clones.
• Biolistic transformation may offer a higher probability of selecting high-performing transgenic events.
• Transformation and tissue culture did not negatively impact key agronomic and sugar quality traits, nor did they induce significant genetic alterations detectable by fingerprinting.