Pistil length and width, pollen diameter, pollen tube elongations, fruitset, seedset and germination rates in european invasive populations of Ludwigia grandiflora subsp. hexapetala in the two floral morphs

Mating system influences local population genetic structure, effective size, offspring fitness and functional variation. Determining the respective importance of self- and cross-fertilization in hermaphroditic flowering plants is thus important to understand their ecology and evolution. The worldwide invasive species, Ludwigia grandiflora subsp. hexapetala (Lgh) presents two floral morphs: one self-compatible short-styled morph (S-morph) and one self-incompatible long-styled morph (L-morph). Most invasive populations worldwide are only composed of self-incompatible L-morphs, which questions the importance of sexual reproduction during the invasion. In this study, we identified the mating systems of western European experimental and natural populations of Lgh by comparing structural characteristics of pollen and style, by studying self- and cross-pollen tube elongations and the viability of the resulting seeds and seedlings in both morphs. The dataset provides measures of pistil length and width; pollen diameter; pollen tube elongations along time after pollination; fruitset, seedset and germination rate in in situ monomorphic L-morph and S-morph populations of western europe invasive Lgh. These data support the manuscript "Late-acting self-incompatible system, preferential allogamy and delayed selfing in the heterostylous invasive populations of Ludwigia grandiflora subsp. hexapetala" by Luis O. Portillo Lemus, Marilyne Harang, Michel Bozec, Jacques Haury, Solenn Stoeckel and Dominique Barloy arguing for a mixed mating system in a European invasive populations of Ludwigia grandiflora subsp. hexapetala.