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The family Cactaceae, which evolved 35 million years ago in the Americas, is one of the most diverse and outlandish assemblages of plants on the planet.
仙人掌科是3500万年前在美洲进化出来的，是全球多样性最高、面貌也最光怪陆离的植物类群之一。
They can branch out as massive trees, rise as 60-foot-tall columns, grow as thick balloons, or fit on a one-cent coin.
它们可能像大树一样长出分枝，巍然耸立如18公尺高的巨柱，或长得像圆鼓鼓的气球，或是小到能安放在一分钱硬币上。
Some are "living rocks" able to handle soils that would desiccate any other plant, while others grow furry white coats to keep them from the elements in the cold Andean altitudes.
有些是“活岩石”，能应付会让其他植物都脱水的土壤，有些还会长出白色绒毛，抵御在安地斯山脉寒冷高海拔地区的严寒。
None of those forms would exist if it weren't for a fundamental advancement: Cacti and other succulents have developed a unique approach to photosynthesis.
这些样貌能够存在，全是因为一个重大的进化：仙人掌和其他多肉植物发展出了一种独特的光合作用形式。
Each time a plant opens its pores to take up the carbon dioxide necessary for energy conversion, some water is lost.
当植物打开气孔、吸进转换能量所需的二氧化碳时，都会失去一些水分。
If this happens frequently during daytime, high temperatures will cause the water to evaporate quickly.
如果这在白天频繁发生，高温就会让水分迅速蒸发。
To prevent that, the desert plants don't open their pores until the sun goes down.
为了避免这种状况，这些沙漠植物会等到太阳下山以后才打开气孔。
Then they absorb atmospheric gas and convert it into malic acid, which is stored in large sacs inside their cells for use the next day.
然后它们会吸收大气中的二氧化碳，转化成苹果酸、储存在细胞内的大囊泡中，准备第二天使用。
It's a process called crassulacean acid metabolism, or CAM.
这个过程称为景天酸代谢（CAM）。
John Cushman, a professor of biochemistry and molecular biology at the University of Nevada in Reno, dreams of cultivating this genetic trait in more plants.
约翰·库希曼是内华达大学雷诺分校的生化与分子生物学家，他梦想着在更多植物身上培育出这个遗传特征。
On the agricultural front, this could lead to more efficient crops that lose less water under drought conditions.
在农业上，这能造就更有效率的作物，碰到干旱状况时损失的水会减少很多。
While that breakthrough may be years or even decades away, researchers have still found one way to make non-cactus plants be at least a little more cactus-like.
虽说这样的突破可能还要等好几年、甚至好几十年，但研究人员已经找到了一种方法，让非仙人掌植物至少更像仙人掌那么一点点。
Before cultivating CAM in new plants, scientists need to alter their leaf anatomy to store malic acid and accommodate larger cells, the processing warehouses for this interaction.
要让新植物获得CAM能力，科学家必须先改变这些植物的叶片构造，以储存苹果酸并容纳较大的细胞，也就是这种交互作用的加工仓库。
One by-product is that plants with larger cells can also hold more water, encouraging succulence, or the ability for their tissues to grow bigger and retain more available moisture.
其中一项副产品就是具有较大细胞的植物也能储存较多水分，这会促进肉质性，也就是能让植物组织长得更大、保留更多可用水分。
In a 2018 paper, Cushman demonstrated engineering tissue succulence in a small, white-flowered weed called mouse-ear cress (Arabidopsis thaliana).
在2018年的论文中，库希曼示范了在一种名为阿拉伯芥的小型白花野草上改造出肉质组织。
A follow-up study, published in 2020, shows that the leaves of an experimental plant grew 40 percent thicker.
在2020年发表的一篇后续研究中则显示某株实验植物的叶片厚度增加了40%。
"It's an exciting adaptation that we still have a lot to learn from," says Cushman.
“这种适应成果令人振奋，我们能从中学习的还有很多，”库希曼说。
For one thing, if a plant can expand the amount of water that it carries within its tissues, it can likely dilute the excessive salts that tend to concentrate in the soil during drought periods.
其一，如果植物能增加自身组织可容纳的水分，或许就能稀释干旱期问聚积在土壤中的多余盐分。
Cushman is applying this science to soybeans, the second largest commodity crop in the U.S., in hopes of radically improving food security.
库希曼已经把这项科学原理应用在美国第二大的商业作物黄豆上，希望能大幅改善粮食安全。
