Laboratory of Tropical Crop Improvement, Department of Biosystems, University of Leuven (K.U. Leuven), Kasteelpark Arenberg 13, Leuven, Belgium.
Mycorrhiza. 2012 Feb;22(2):157-63. doi: 10.1007/s00572-011-0422-y. Epub 2011 Dec 7.
The root-knot nematode Meloidogyne incognita poses a worldwide threat to agriculture, with an increasing demand for alternative control options since most common nematicides are being withdrawn due to environmental concerns. The biocontrol potential of arbuscular mycorrhizal fungi (AMF) against plant-parasitic nematodes has been demonstrated, but the modes of action remain to be unraveled. In this study, M. incognita penetration of second-stage juveniles at 4, 8 and 12 days after inoculation was compared in tomato roots (Solanum lycopersicum cv. Marmande) pre-colonized or not by the AMF Glomus mosseae. Further life stage development of the juveniles was also observed in both control and mycorrhizal roots at 12 days, 3 weeks and 4 weeks after inoculation by means of acid fuchsin staining. Penetration was significantly lower in mycorrhizal roots, with a reduction up to 32%. Significantly lower numbers of third- and fourth-stage juveniles and females accumulated in mycorrhizal roots, at a slower rate than in control roots. The results show for the first time that G. mosseae continuously suppresses root-knot nematodes throughout their entire early infection phase of root penetration and subsequent life stage development.
根结线虫 Meloidogyne incognita 对农业构成了全球性威胁，由于大多数常用杀线虫剂因环境问题而被撤出，因此人们对替代控制方法的需求日益增加。丛枝菌根真菌 (AMF) 对植物寄生线虫的生物防治潜力已得到证实，但作用模式仍有待阐明。在这项研究中，比较了在接种后 4、8 和 12 天，第二阶段幼虫在预先接种或未接种 AMF Glomus mosseae 的番茄根（Solanum lycopersicum cv. Marmande）中的穿透情况。在接种后 12 天、3 周和 4 周，还通过酸性品红染色观察了幼虫在对照和菌根根中的进一步发育阶段。在菌根根中，穿透明显较低，减少了 32%。在菌根根中积累的第三和第四阶段幼虫和雌性数量明显较少，并且比对照根中的积累速度较慢。结果首次表明，G. mosseae 连续抑制根结线虫，贯穿其整个早期侵染阶段的根穿透和随后的生活阶段发育。
