抗干旱作物和'Designer'水稻

    This is the VOA Special English Agriculture Report.
    这里是美国之音慢速英语农业报道。
     
    A discovery in a laboratory could help lead to new generation of drought-resistant crops. Drought conditions cause plants to produce a stress hormone called abscisic acid. This chemical activates a set of protein molecules called receptors. These receptors then activate a series of changes to help the plant survive.
    一项实验室发现可能有助于带来新一代耐旱作物。干旱状况会导致作物产生一种被称为脱落酸的应激激素。这种化学物质会激活一套被称为受体的蛋白质分子。这些受体随即会激活一系列变化来帮助植物存活。
     
    The natural reaction of the receptors is to close so-called guard cells on and inside the leaves. That closure decreases water loss and stops the plant from growing to save water during a drought.
    受体的自然反应就是关闭植物叶子内外的所谓保卫细胞。保卫细胞的关闭会降低水分流失,使植物在干旱时期停止生长以节约水分。
     
    Researchers say they have discovered a way to "supercharge," or increase, this reaction. Sean Cutler at the University of California, Riverside, led the team. The scientists engineered abscisic acid receptors that can be turned on at will and stay on. They tested hundreds of versions of engineered receptor genes until they found ones that worked right together.
    研究人员说,他们已经发现一种“增压”方式来增强这种反应。加州大学河滨分校的肖恩·卡特勒(Sean Cutler)负责这个研究小组。科学家人工改造的脱落酸受体可以随意开启并保持这一状态。他们在发现合适基因前检测了数百种人工改造受体基因。
     
    The team worked with Arabidopsis, a plant often used in experiments. The results recently appeared in the Proceedings of the National Academy of Sciences.
    该小组采用了一种实验常用的植物拟南芥。研究结果最近发表在《美国国家科学院学报》上。
     
    Professor Cutler says testing the new receptors in the field may take several years. He also points out that drought is not the only cause of plant stress.
    卡特勒教授表示,实地检测这种新受体可能需要几年时间。他还指出,干旱不是植物抗逆性的唯一原因。
     
    SEAN CUTLER: "If a plant grows in the deserts normally, like a cactus, what would be stressful for a crop plant is not stressful for a cactus because it has evolved to live in that ecological niche where the water is very rare. So it would really mean, you know, any significant deviation from the normal or ideal growth conditions for an organism."
    卡特勒:“如果一种植物像仙人掌一样在沙漠生长。对这种植物来说可能会产生巨大抗逆性,但对仙人掌来说不会。因为仙人掌已经进化到在那种极度缺水的生态小生境中存活。所以它可能意味着一种有机体在正常和理想生长环境的显著偏差。”

    In another development, scientists have produced a new system for analyzing genetic markers in rice plants. A genetic marker is a DNA sequence with a known location. It can help scientists identify nearby genes linked to individual qualities, or traits.
    另据报道,科学家已经制造出分析水稻遗传标记的新系统。遗传标记是一种位置已知的DNS序列。它可以帮助科学家确定与特质或性状相关的邻近基因。
     
    Anna McClung and Georgia Eizenga are genetic scientists with the United States Department of Agriculture. Their new system will let researchers genetically "fingerprint" rice varieties and gain a better understanding of the markers.
    安娜·麦克朗(Anna McClung)和乔治亚·艾森格(Georgia Eizenga)是就职于美国农业部的遗传学家。他们的新系统可以让研究人员从基因上鉴别水稻品种,并更好地了解标记。

    Until now, breeders have been limited to using perhaps two hundred markers. But modern technology lets scientists identify differences throughout the plant's genome, its genetic map. Ms. McClung says that means the ability to identify new genes that control biological pathways.
    到目前为止,育种者限于使用两百种左右的标记。但现代科技能够让科学家通过遗传图谱,也就是植物基因组来确定差异。麦克朗女士说,这意味着有能力识别控制生物途径的新基因。
     
    ANNA McCLUNG: "You know, biological pathways in the plant that may control yield, disease resistance, nutritional quality ... "
    麦克朗:“植物的生物途径可以控制产量,抗病性,营养品质...”
     
    The finding could make it easier in the future for farmers to grow "designer rice," rice bred to meet their specific needs.
    该发现可能使农民将来种植满足他们特定需求的和'Designer'水稻更为容易。

    (51VOA.COM对本文翻译享有全部权利,未经授权请勿转载,违者必究!)