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Scientists have discovered more details about how plants use water. Their findings could help to engineer plants that grow better and more effectively in conditions with higher levels of carbon dioxide.
Plants naturally take in carbon dioxide they need for photosynthesis[光合作用], the process of changing light
energy to chemical energy. The carbon dioxide enters the plants through tiny holes or pores[气孔] on the surface of leaves.
However, each time a plant takes in one molecule[分子] of carbon dioxide gas, it loses hundreds of water molecules.
Scientists say plants lose 95% of the water they take in through these pores. Some plants’ pores can tighten to save water during conditions of high carbon dioxide. Other plants are not able to do this as well. Now, scientists know how these tiny pores tighten in plants.
Julian Schroeder is a professor of biology at the
University of California, San Diego. Mr. Schroeder says that carbon dioxide levels in the atmosphere are much higher now than they were in the past. However, he says, many plants are not closing their pores in order to hold in more water.
He and his team have identified proteins[蛋白质] that control the tightening of a plant’s pores. The proteins are enzymes[酶] called carbonic anhydrases[碳酸酐酶]. The
findings were published in the journal Nature Cell Biology. Mr. Schroeder believes the enzymes could be changed in some plants to increase their ability to store water.
The researchers added carbonic anhydrase genes to plants that do not react to higher levels of carbon dioxide. They observed that for every molecule of carbon dioxide taken in by the plants, they lost 44% less water.
The scientists say the photosynthesis process
continued normally in these plants. They say this suggests that changing plants to save more water will not affect plant growth. This method might be used to help engineer food crops that are resistant to extremely dry conditions. The discovery could help farmers meet a growing demand
for food as water supplies decrease. However, the
scientists say more research is needed.
科学家们发现了更多关于植物如何利用水份的具体情况。这些发现有助于人们规划植物种植,使其在二氧化碳浓度高的情况下生长得更快更好。
植物进行光合作用——也就是将光能转化为化学能的过程——的时候,会自然地吸收二氧化碳。二氧化碳通过小孔或叶片表面的气孔进入植物内部。
然而,每当植物吸收一个二氧化碳分子,它就会失去数百个水分子。
科学家称,通过这些气孔,植物会流失近95%的水分。一些植物可以在二氧化碳浓度高时收缩气孔以防止水分流失,其他植物则没有这个能耐。现在,科学家们已经知道这些植物的细小气孔如何进行收缩。
朱利安·施罗德是(美国)加利福尼亚大学圣地亚哥分校的生物学教授。施罗德教授说,现今大气中的二氧化碳浓度比以前高了很多,然而很多植物并没有关闭气孔来保住水分。
他及其研究小组已经识别出用来控制植物气孔收缩的蛋白质。这种蛋白质是一种酶,名叫做碳酸酐酶。这项发现发表在《自然细胞生物学》期刊上。施罗德教授相信,通过改变植物中的酶,植物的储水能力会得到提高。
研究者将碳酸酐酶基因注入一些无法对高浓度二氧化碳作出反应的植物中。他们发现,这些植物每吸收一个二氧化碳分子,就会少流失44%的水分。
科学家表示,这些植物可以照常进行光合作用,也就是说通过改变基因来保留水分对植物的生长并无影响。这种方法也许可以用来培育抵抗极端干旱气候的粮食作物。同时,这一发现还可以帮助农民在供水量减少的情况下满足粮食需求的增长。尽管如此,科学家称目前仍需进一步研究。
Plants naturally take in carbon dioxide they need for photosynthesis[光合作用], the process of changing light
energy to chemical energy. The carbon dioxide enters the plants through tiny holes or pores[气孔] on the surface of leaves.
However, each time a plant takes in one molecule[分子] of carbon dioxide gas, it loses hundreds of water molecules.
Scientists say plants lose 95% of the water they take in through these pores. Some plants’ pores can tighten to save water during conditions of high carbon dioxide. Other plants are not able to do this as well. Now, scientists know how these tiny pores tighten in plants.
Julian Schroeder is a professor of biology at the
University of California, San Diego. Mr. Schroeder says that carbon dioxide levels in the atmosphere are much higher now than they were in the past. However, he says, many plants are not closing their pores in order to hold in more water.
He and his team have identified proteins[蛋白质] that control the tightening of a plant’s pores. The proteins are enzymes[酶] called carbonic anhydrases[碳酸酐酶]. The
findings were published in the journal Nature Cell Biology. Mr. Schroeder believes the enzymes could be changed in some plants to increase their ability to store water.
The researchers added carbonic anhydrase genes to plants that do not react to higher levels of carbon dioxide. They observed that for every molecule of carbon dioxide taken in by the plants, they lost 44% less water.
The scientists say the photosynthesis process
continued normally in these plants. They say this suggests that changing plants to save more water will not affect plant growth. This method might be used to help engineer food crops that are resistant to extremely dry conditions. The discovery could help farmers meet a growing demand
for food as water supplies decrease. However, the
scientists say more research is needed.
科学家们发现了更多关于植物如何利用水份的具体情况。这些发现有助于人们规划植物种植,使其在二氧化碳浓度高的情况下生长得更快更好。
植物进行光合作用——也就是将光能转化为化学能的过程——的时候,会自然地吸收二氧化碳。二氧化碳通过小孔或叶片表面的气孔进入植物内部。
然而,每当植物吸收一个二氧化碳分子,它就会失去数百个水分子。
科学家称,通过这些气孔,植物会流失近95%的水分。一些植物可以在二氧化碳浓度高时收缩气孔以防止水分流失,其他植物则没有这个能耐。现在,科学家们已经知道这些植物的细小气孔如何进行收缩。
朱利安·施罗德是(美国)加利福尼亚大学圣地亚哥分校的生物学教授。施罗德教授说,现今大气中的二氧化碳浓度比以前高了很多,然而很多植物并没有关闭气孔来保住水分。
他及其研究小组已经识别出用来控制植物气孔收缩的蛋白质。这种蛋白质是一种酶,名叫做碳酸酐酶。这项发现发表在《自然细胞生物学》期刊上。施罗德教授相信,通过改变植物中的酶,植物的储水能力会得到提高。
研究者将碳酸酐酶基因注入一些无法对高浓度二氧化碳作出反应的植物中。他们发现,这些植物每吸收一个二氧化碳分子,就会少流失44%的水分。
科学家表示,这些植物可以照常进行光合作用,也就是说通过改变基因来保留水分对植物的生长并无影响。这种方法也许可以用来培育抵抗极端干旱气候的粮食作物。同时,这一发现还可以帮助农民在供水量减少的情况下满足粮食需求的增长。尽管如此,科学家称目前仍需进一步研究。