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Fernández-Aparicio M, García-Garrido JM, Ocampo JA & Rubiales D (2010). Colonisation of field pea roots by arbuscular mycorrhizal fungi reduces Orobanche and Phelipanche species seed germination. Weed Research 50, 262–268. Pea ( Pisum sativum) is an important grain legume crop whose cultivation in the Mediterranean basin and West Asia is severely constrained by infection by the weedy root parasite Orobanche crenata (crenate broomrape). Pea is a false host of other species such as O. minor, O. foetida and Phelipanche aegyptiaca. In the present experiments, we demonstrate that seed germination of the Orobanche and Phelipanche species examined is reduced in the presence of root exudates from pea plants colonised by arbuscular mycorrhizal (AM) fungi, Glomus mosseae and G. intraradices. Reduced germination was due to the effect of the AM fungi and not to the microbial populations potentially present in the soil inoculum. This protective effect of mycorrhizae was noticeable after 35 days of AM colonisation for O. crenata, O. foetida and P. aegyptiaca, but at least 45 days of colonisation were needed to get some reduction of O. minor germination. [ABSTRACT FROM AUTHOR]

Fernández-Aparicio M, Rispail N, Prats E, Morandi D, García-Garrido JM, Dumas-Gaudot E, Duc G & Rubiales D (2009). Parasitic plant infection is partially controlled through symbiotic pathways. Weed Research. 50, 76–82. Legumes are unique in interacting with Rhizobium, arbuscular mycorrhizal (AM) fungi, and parasitic plants. To dissect common parts of these three plant–organism interactions, infection by Orobanche crenata was studied in mutants with altered symbiotic phenotypes of Medicago truncatula and Pisum sativum. Orobanche crenata inoculation of mutant lines carrying defective mutation in the genes dmi2/ sym19 and dmi3 resulted in an increase in O. crenata establishment. Similarly, inoculation of mutants carrying mutation in the gene sunn/ sym29 that controls the autoregulation mechanism of the symbiosis, also lead to a significant increase in haustoria formation. Altogether, our results suggest that parasitic plant infection is partly controlled by both the conserved symbiotic pathway that mediates symbiont recognition and establishment and the autoregulation mechanism that regulates the extent of colonisation by Rhizobium and AM fungi. [ABSTRACT FROM AUTHOR]