Engineering of the soybean microbiome to suppress root lesion nematodes

• Applicant: Dr. Ahmed Elhady Gomaa
• Subject Area: Soil Sciences ; Microbial Ecology and Applied Microbiology ; Plant Cultivation, Plant Nutrition, Agricultural Technology ; Plant Breeding and Plant Pathology
• Term: from 2019 to 2022
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 420659973

Plant parasitic nematodes (PPN) are economically important soil-born threats worldwide.Globally, 12.6% crop losses were attributed to PPN. Nematode management is a challenge because nematicides have been mostly banned, and resistant varieties or non-host crops are often not available or not profitable. Efficient, sustainable methods for control have become an urgent need. Plants in their agroecosystems are part of multi-organismal associations, called phytobiomes that support them in defence against PPN. Plants modulate the microbiome in their rhizosphere and thereby affect the subsequent plants that are thereafter growing in the same soil. This could be the main reason for the often-reported plant-soil feedback in crop rotations, and might be harnessed in control of PPN. Following the implementation of the strategy for increasing the production of protein crops in Europe, soybean varieties adapted to temperate climate are grown on increasing acreages. We showed that root lesion nematodes (RLN, Pratylenchus spp.) are a major threat for soybean production in Germany. They not only damage the root but also significantly affect symbiotic N2- fixation in the nodules. By inoculating certain rhizosphere microbiomes, we could reduce root invasion and reproduction of RLN on soybean. In this proposed study, we aim to understand this plant-soil feedback of those pre-crops, which modulate the rhizosphere microbiome of soybean in a way that RLN are suppressed. It will be investigated, which microbial taxa in the rhizosphere correlate in abundance with the suppression of RLN, and whether this effect depends on the composition of the initial bulk soil microbiome. We will investigate, how modulated microbiomes suppress RLN (direct or plant-mediated), and how suppressive microbiomes shape the plant response to RLN.

• DFG Programme: Research Grants