Citrus plants are traditionally cultivated in tropical and subtropical climates due to their susceptibility to cold stress. This might pose an issue for citrus growers since climate change has made the weather highly volatile and cold spells mean lower citrus yield and subpar fruit quality.

However, in a recent study published in Horticulture Research, an international team of scientists from Guangxi University of Chinese Medicine and Huazhong Agricultural University might have found a solution by working with a citrus plant resistant to colder weather. 

The team of researchers found that a gene in Poncirus trifoliata, a hardy citrus relative known as trifoliate orange or hardy orange, is what's behind the plant's resistance to colder weather.

The PtrPAT1 gene, the report says, "plays a crucial role in cold tolerance by stimulating the biosynthesis of GB, providing a potential genetic tool to improve cold resistance in commercial citrus crops." 

Scientists introduced the gene PtrPAT1 in transgenic tobacco plants through genetic modification and noticed this process increased GB accumulation, boosted antioxidant enzyme activity, and enhanced cold tolerance. 

This shows, according to the study, that harnessing the gene could lead to creating genetically modified citrus varieties with enhanced resilience to cold stress. 

Co-corresponding author of the study, Dr. Ji-Hong Liu, said that this marks a major breakthrough in understanding how citrus plants manage cold stress.

"Identifying PtrPAT1 and its role in regulating GB biosynthesis opens new avenues for developing cold-resistant citrus varieties, which are vital as climate change continues to impact agricultural productivity," he explained.