Mechanisms of regulation of arbuscular mycorrhizal colonisation with root exudates

根系分泌物调节丛枝菌根定植的机制

• 批准号: 12660056
• 负责人: TAWARAYA Keitaro
• 金额: $ 2.24万
• 依托单位: Yamagata University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2000
• 资助国家: 日本
• 起止时间: 2000 至 2001
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-12660056/
• 关键词: Arbuscular mycorrhizal fungi; Root exudates; hyphae; phosphorus deficiency; Gigaspora margarita; Onion; タマネギ

Root exudates of phosphorus (P) deficient onion promote the growth of arbuscular mycorrhizal (AM) fungi. Mechanisms of promotion is still unknown. Effect of purified fractions with chromatography on hyphal growth was investigated by mass collection of P deficient onion root exudates. Onion (Allium cepa cv. Senshuchukoki) was grown in solution culture of three P concentrations (0.0 (P0), 0.1 (P0.1) and 8.0 (P8)) and root exudates were collected. Root exudates were fractionated to hydrophilic and hydrophobic fractions with Amberlite XAD-4 resin and further purified by silicagel-TLC (Hexane:Ethylacetate 8:1) , ODS-TLC (90% Methanol) and Sephadex LH-20 column chromatography. Spores of AM fungi Gigaspora margarita were incubated in these fractions and deionized water (control) for 10 days. Hyphal length and hyphal branch were measured. Hyphal length and branch were larger in P0 and P0.1 treatments than that in control and P8 treatments. B1 fraction (Rf0.21) was obtained by ODS-TLC and increased hyphal length and branch. More than 75% of hyphal branch in B1 consisted of secondary order branch. It is suggested that P deficient root exudates contain the substances which promote hyphal elongation and branch and these substances increase opportunity of contact between symbiont and host.

缺磷洋葱的根部分泌物促进丛枝菌根（AM）真菌的生长。晋升机制仍不清楚。通过大量收集缺磷洋葱根分泌物，研究了层析纯化的级分对菌丝生长的影响。洋葱（Allium cepa cv. Senshuchukoki）在三种 P 浓度（0.0 (P0)、0.1 (P0.1) 和 8.0 (P8)）的溶液培养物中生长，并收集根分泌物。用 Amberlite XAD-4 树脂将根分泌物分级为亲水性和疏水性级分，并通过硅胶-TLC（己烷：乙酸乙酯 8:1）、ODS-TLC（90% 甲醇）和 Sephadex LH-20 柱色谱进一步纯化。 AM 真菌 Gigaspora margarita 的孢子在这些级分和去离子水（对照）中孵育 10 天。测量菌丝长度和菌丝分支。 P0和P0.1处理的菌丝长度和分枝均大于对照和P8处理。通过ODS-TLC获得B1级分(Rf0.21)并增加菌丝长度和分枝。 B1中75%以上的菌丝分枝由二级分枝组成。提示缺磷根系分泌物中含有促进菌丝伸长和分枝的物质，这些物质增加了共生体与寄主接触的机会。

项目成果

Tawaraya, K.: "Inhibition of pre-symbiotic hyphal growth of arbuscular mycorrhizal fungus Gigaspora margarita by root exudates of Lupinus"spp. Soil Sci. Plant Nutr.. 48. 117-120 (2002)

Tawaraya，K.：“羽扇豆根分泌物对丛枝菌根真菌 Gigaspora margarita 的共生前菌丝生长的抑制”。

俵谷 圭太郎: "Inhibition of pre-symboiotic hyphal growth of arbuscular mycorrhizal fungus Gigaspora margarita by root exudates of Lupinus spp"Soil Sci.Plant Nutr.. 48. 117-120 (2002)

Keitaro Tawaraya：“羽扇豆根分泌物对丛枝菌根真菌 Gigaspora margarita 的共生前菌丝生长的抑制”Soil Sci.Plant Nutr.. 48. 117-120 (2002)

Tawaraya, K.: "Elucidation of increased hyphal growth of Gigaspora margarita by root exudates"Abstracts of the annual meeting, Japanese Society of Soil Science and Plant Nutrition. Vol. 47. 56 (2001)

Tawaraya, K.：“通过根分泌物阐明玛格丽塔大孢子菌菌丝生长的增加”年会摘要，日本土壤科学和植物营养学会。

俵谷圭太郎: "根の浸出物によるGigaspora margaritaの菌糸成長促進機構の解析"日本土壌肥料学会講演要旨集. 46. 56 (2001)

Keitaro Tawaraya：“根分泌物促进Gigaspora margarita菌丝生长的机制分析”日本土壤肥料学会摘要46. 56（2001）。

俵谷 圭太郎: "根の浸出物によるGigaspora margaritaの菌糸成長促進機構の解析"日本土壌肥料学会講演要旨集. 46. 56 (2001)

Keitaro Tawaraya：“根分泌物促进Gigaspora margarita菌丝生长的机制分析”日本土壤肥料学会摘要46. 56（2001）。