《法国阿格瑞:专注多元菌株微生物制剂技术,开发生物固氮新途径——叶围固氮菌N-LEAF》

  • 来源专题:现代化工
  • 编译者: 武春亮
  • 发布时间:2024-07-15
  • 法国阿格瑞植物营养公司(Agronutrition SAS, 简称AGN)始于1969年,总部位于法国南部城市图卢兹,是法国戴商高士集团(De Sangosse Group)的全资子公司,同时也是欧洲生物刺激素产业联盟EBIC理事会成员。作为全球作物精准营养专家,法国阿格瑞(AGN)业务遍布全球60多个国家。
    法国阿格瑞(AGN)发展的核心是精准营养高效技术的创新、研制,并基于Physio-efficience
    ®
    技术理念,致力于研发、生产和销售优质的精准农业营养和生物刺激素及生物肥料系列产品,为植物健康生长全程提供科学、精准营养解决方案,助力全球农业可持续发展。2022年,法国阿格瑞(AGN)的生物肥料技术(BIO-Fertilizer)研发中心,历经10年的菌株筛选、选配,开发出了一款含6种复合菌株的叶围固氮菌悬浮剂产品N-LEAF。
    众所周知,氮是植物蛋白质、核酸和叶绿素等关键成分的基础元素,是所有生物体必需的。空气中约有78%的氮气,然而绝大多数植物不能直接利用空气中的氮气,必须依赖从土壤中吸收氮肥以满足自身生长的需求。然而施用到土壤的氮肥有超过50%流失到环境中:要么进入大气,要么渗入地下水,或者通过径流进入溪流、河流和湖泊,造成环境污染!当下,全球众多企业及相关研究单位致力于提高养分生物利用率,实现减肥增效,实现农业作业与环境保护和谐、持续发展,而针对氮元素,生物固氮是一个提高氮生物利用率有效方式之一。生物固氮主要存在于豆科作物及一些可以和根瘤菌产生共生关系的作物,近几年根部共生固氮菌类产品开发,为生物固氮开辟了新的市场和机遇,但根部固氮类产品的应用推广也遇到了很多挑战,比如接种问题,目前很多种子,如玉米和小麦种子应用化学杀菌的种衣剂产品,加大了接种菌剂的难度。
    2022年,法国阿格瑞(AGN)的生物肥料技术(BIO-Fertilizer)研发中心,历经10年的菌株筛选、选配、验证,开发出了一款含6种复合多元菌株的叶围固氮菌液体制剂产品N-LEAF。N-LEAF叶围固氮菌是基于植物周围微生物生存的环境条件(植物微生态圈),即植物根际微生物圈、植物叶围、植物内圈进行研究,同时,植物叶围是地球上微生物最集中的环境之一,仅次于土壤根围微生物。据估计,全世界陆生植物的叶面积超过 6.4 x 10
    8
    km
    2
    (Andrews和Harris, 2000)。叶围微生物由细菌、病毒、真菌、藻类和古细菌组成,且以细菌为主。
    法国阿格瑞(AGN)利用生物膜(BIOFILM)技术,对不同菌属、不同菌株在植物叶围下生存及固氮能力进行验证、筛选,得到3种叶围细菌株系(phyllosphere bacteria),2种甲基杆菌株系(
    Methylobacterium
    ),1种节肢杆菌株系(
    Arthrobacter
    ),并将3种菌属6种菌株有机结合在一起,开发出N-LEAF叶围固氮菌悬浮剂产品。
    N-LEAF的微生物菌剂是如何在叶面喷施后生存、繁殖的呢?
    通常,植物在生长过程中叶面会释放甲醇。这是植物新陈代谢过程中的废物,N-LEAF中两种菌株的甲基细菌菌株将利用这些甲醇生长、繁殖;N-LEAF中的节肢杆菌菌株虽然不能将甲醇作为能源使用,但是它们通过消耗叶子释放的单糖来维持生存、繁殖。
    N-LEAF的微生物菌剂在叶面喷施后功能特点有哪些?
    1.
    固定大气中氮源,提高植物体氮的吸收利用率
    :将空气中的N
    2
    固定,转化成铵态氮,供应给作物,为作物生长补充氮源。
    2.
    促进植物合成生长素
    :N-LEAF诱导作物产生吲哚乙酸(生长素)和细胞分裂素,促进植物生长,增强叶片光合速率。
    3.
    占据叶围的物理空间
    :植物叶围细菌的数量是非常高的 (10
    9
    UFC/ML),N-LEAF叶围固氮菌的应用,使得有益菌株占据物理′′叶′′空间,从而限制其他杂细菌和病原菌的增殖,从而鼓励这些有益菌株在叶片增殖和生存。另外,我们的细菌菌株也会产生一种叫做乙酰素的小代谢物,它会刺激SPR(系统性植物抗性物质)合成。
    N-LEAF的微生物菌剂在叶面喷施后的具体效果案例有哪些?
    案例一:
    时间:2021年5月15日
    地点:Prunay Le Gillon – 法国
    作物:马铃薯
    实验处理:
    ? CONTROL 70%: X=84 kg N/ha
    ? CONTROL 100%: 120 kg N/ha
    ? PRODUCT B + X=84 kg N/ha
    ? N-LEAF: 0.5L/ha + X=84 kg N/ha
    结果分析:
    马铃薯叶面喷施N-LEAF叶围固氮菌悬浮剂0.5L/公顷,相对对照产品马铃薯产量提高7.9%。另外,应用N-LEAF 0.5L/公顷,在氮投入量减少30%的条件下,维持产量增长。
    案例二:
    时间:2023年4月13日
    地点:Derekegyház-Tompahát- 匈牙利
    作物:向日葵
    实验处理:
    ? CONTROL
    ? PRODUCT B:0.333kg/ha PRODUCT B
    ? N-LEAF: 0.5l/ha N-LEAF
    结果分析:
    向日葵叶面喷施N-LEAF叶围固氮菌悬浮剂0.5L/公顷,相对对照产量提高7.6%,每公顷增产177公斤,产量达2501公斤/公顷。
    N-LEAF叶围固氮菌悬浮剂不受作物根部土壤环境的影响,通过叶面喷施就能固氮,提高植物氮的生物利用率,正确应用可以减少25%-30%化学氮肥投入;N-LEAF叶围固氮菌悬浮剂可促进作物茁壮生长,增强作物光合速率,让更多有益菌占据作物叶围的物理空间,降低了病原菌的增殖、传播。
    联系电话:0531-84244081
    网址:
    www.agronutrition.com
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  • 原文来源:http://cn.agropages.com/News/NewsDetail---32079.htm
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Related work is also funded by the Resnick Sustainability Institute. -------------------------------------------------------------------------------- Journal Reference: 1.Matthew J. Chalkley, Trevor J. Del Castillo, Benjamin D. Matson, Joseph P. Roddy, Jonas C. Peters. Catalytic N2-to-NH3 Conversion by Fe at Lower Driving Force: A Proposed Role for Metallocene-Mediated PCET. ACS Central Science, 2017; 3 (3): 217 DOI: 10.1021/acscentsci.7b00014 --------------------------------------------------------------------------------