A new paper ‘Host influence on germination and reproduction of the facultative hemi-parasitic weed Rhamphicarpa fistulosa’ was published in Annals of Applied biology in which the germination ecology and parasitism of the facultative parasitic plant, Rhamphicarpa fistulosa (Rice Vampireweed) were investigated in comparison with the obligate parasitic plant Striga hermonthica (Purple Witchweed). We hypothesized that, being a wetland species, germination of R. fistulosa is stimulated by light and high soil moisture. The study revealed that light and completely saturated soils were a requirement for germination, demonstrating that germination requirements of R. fistulosa are typical of species that grow in environments with fluctuating water levels. While germination of S. hermonthica was strongly advanced by the presence of root exudates and GR24 but completely absent in water, the germination of R. fistulosa was similar in all three treatments. This shows that R. fistulosa seed germination is independent of host presence. Growth of R. fistulosa in the presence of a rice plant, however, resulted in a 3.7 times higher seed production and 15% larger average seed size than in host absence. These findings suggest that for facultative parasitic plant species, contrary to obligate parasitic plants (like Striga) a more opportunistic germination strategy may be superior. The paper concludes with discussing the implications of the findings for management of R. fistulosa in rice cultivation.
Please refer to the paper as: Kabiri, S., van Ast, A., Rodenburg, J., Bastiaans, L., 2016. Host influence on germination and reproduction of the facultative hemi-parasitic weed Rhamphicarpa fistulosa. Annals of Applied Biology 169, 144-154.
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