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to agriculture, with an increasing demand for alternative control options since most common nematicides are being withdrawn due to environmental concerns.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.
Strawberry growers could reduce irrigation inputs by up to 40 per cent while still maintaining yields, by inoculating their plants with naturally-occurring beneficial soil-dwelling fungi, researchers at Kent’s East Malling Research (EMR) have found.
Two different species of arbuscular mycorrhizal fungi, or the two in combination, gave similar beneficial results over the control plants in trials by a team that was led by University of Kent PhD student Louisa Robinson-Boyer.
“While it has been long-known that these beneficial fungi can have positive effects on plant nutrient uptake, protect plants from infection by pathogens and buffer them against adverse environmental stresses, this work provides an opportunity to reduce irrigation by 40 per cent and still retain required growth and yield outputs,” she said.
“Working with these fascinating fungi has great potential to address some of the future food security challenges being raised by climate change. This work will greatly assist with future sustainable food production – maintaining yields while reducing inputs.”
The results are published in the Mycorrhiza journal. Arbuscular mycorrhizal fungi occur in most ecosystems, but their levels are much decreased across intensive agricultural systems, mainly due to soil tillage and the use of fertilisers.