China: Into the wild with watermelons in search of disease resistance
Fei realised that wild watermelons, which are bitter and unpalatable, were more resistant to disease. After comparing the DNA of the wild plant with cultivated varieties, he concluded that the resistance had been lost in domestication.
“We found that during domestication, people only focus on developing sweet watermelons, but they ignore the disease-resistance aspect. And when we compared those genomes, we found a lot of pathogen-resistant genes in wild watermelons that were lost in the cultivated one. That’s unfortunate, so now we want to bring back the disease-resistance,” Fei said.
Fei worked with researchers from several countries such as China and France, to complete the project.
“[Collaborating] helped a lot. If it were only my group, we would not have been able to do the project because we don’t have certain expertise or facilities,” Fei said.
To simplify the process of generating 20 different watermelon sequences, the team first created a “reference genome” from the one watermelon. The team used this reference as a template in order to find the other watermelon genes more efficiently, as all of the plants have similar genetic sequences, Fei said.
Fei and his team are currently working on the introduction of disease-resistant genes into cultivated plants. This is not a simple process, however, because the researchers must first conduct a series of tests to ensure that the new disease-resistance genes will not affect the quality of the taste of cultivated watermelon, according to Fei.
“If you introduce disease-resistant genes into the cultivated plant, the sweetness may become lost. You want to introduce this disease-resistant gene but still make sure the fruit is high quality,” Fei said.
Source: cornellsun.com
