The researchers' first subject was the tobacco plant.

研究人员第一个研究对象是烟草。

If the tobacco plant is eaten, it can quickly poison a person.

如果吃了烟草，人就会很快中毒。

They infect a tobacco plant with the gene-carrying virus by scratching the virus on its leaves.

通过把这种带有基因的病毒擦到叶子上，来感染烟草。

While he was exploring the shores of America, he saw the Indians smoking the leaves of the tobacco plant.

他在美洲海岸探险的时候，看到印第安人抽烟草的叶子。

Next, you infect the tobacco plant with the bacterium. Inside the plant, the protein is produced in large quantities.

接着，用这种细菌来感染烟草叶，这种蛋白在烟草叶中就会大量的合成。