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Papers by Lilian Ceballos
HAL is a multidisciplinary open access archive for the deposit and dissemination of scientific re... more HAL is a multidisciplinary open access archive for the deposit and dissemination of scientific research documents, whether they are published or not. The documents may come from teaching and research institutions in France or abroad, or from public or private research centers. L'archive ouverte pluridisciplinaire HAL, est destinée au dépôt et à la diffusion de documents scientifiques de niveau recherche, publiés ou non, émanant des établissements d'enseignement et de recherche français ou étrangers, des laboratoires publics ou privés.
We determined the localization of phenolic compounds in dormant seeds of two American species of ... more We determined the localization of phenolic compounds in dormant seeds of two American species of Sesbania (Fabaceae) by a combination of histochemical and biochemical methods. Phenolics are located in different layers of the seed coat and in the subhilar parenchyma. We then investigated the release of these compounds by imbibing seeds of both species. The annual S. 6esicaria releases the flavonoid luteolin, with minor amounts of proanthocyanidins, whereas the perennial S. drummondii releases mostly proanthocyanidins. Types and amount of allelochemicals exuded seem related to ecology and life history traits of each species. We then showed mobilisation of these allelochemicals by histochemical sections in imbibing seeds of both species. Histological structure is similar in both species. A number of characters (lens, subhilar parenchyma, tracheid bar) appear to function together to facilitate the exudation of compounds that protect young seedlings. Furthermore, the spatial organization of these organs with interlocking function allows retrieval of defensive substances stored in the seed, and their redeployment is beneficial for seedling survival. We hypothesize that optimisation of the chemical defences allocated to the seed by the maternal parent confers a significant advantage to the seedling, whose energy is mainly committed to growth.
Developing seeds of Sesbania drummondii are attacked by nymphs and adults of the bug Hyalymenus t... more Developing seeds of Sesbania drummondii are attacked by nymphs and adults of the bug Hyalymenus tarsatus (Heteroptera: Alydidae), which kill some seeds and weaken others. Parasitism by this piercing-sucking insect reduced the resources for the future seedling and affected seed physiology, including dormancy and exudation of allelochemicals of imbibing seeds. Seeds attacked by H. tarsatus had reduced mass (20-80% reduction, depending on intensity of attack). Heavy attack led to irregular shape, changes in seed coat color, and disruption of dormancy. While intact seeds did not imbibe during a 48-hour test in water, a high proportion of bug-attacked seeds germinated, from 51 to 94%, depending on intensity of attack. Attack by H. tarsatus also affected accumulation of allelochemicals and their exudation by imbibing seeds. There were no quantitative differences in proanthocyanidin content between exudates of attacked and unattacked seeds. In contrast, concentrations of total condensed ta...
Chemoecology, 1998
... Lilian Ceballos1,2, Martine Hossaert-McKey2, Doyle McKey1,3 and Claude Andary2 ... American s... more ... Lilian Ceballos1,2, Martine Hossaert-McKey2, Doyle McKey1,3 and Claude Andary2 ... American species of Sesbania that present contrasts in several ecological and life history traits: Sesbania 6esicaria (Jacq.) Ell., an annual species, and S. drummondii (Rydb.) Cory, a perennial ...
Acta Botanica Gallica, 2001
HAL is a multidisciplinary open access archive for the deposit and dissemination of scientific re... more HAL is a multidisciplinary open access archive for the deposit and dissemination of scientific research documents, whether they are published or not. The documents may come from teaching and research institutions in France or abroad, or from public or private research centers. L'archive ouverte pluridisciplinaire HAL, est destinée au dépôt et à la diffusion de documents scientifiques de niveau recherche, publiés ou non, émanant des établissements d'enseignement et de recherche français ou étrangers, des laboratoires publics ou privés.
We determined the localization of phenolic compounds in dormant seeds of two American species of ... more We determined the localization of phenolic compounds in dormant seeds of two American species of Sesbania (Fabaceae) by a combination of histochemical and biochemical methods. Phenolics are located in different layers of the seed coat and in the subhilar parenchyma. We then investigated the release of these compounds by imbibing seeds of both species. The annual S. 6esicaria releases the flavonoid luteolin, with minor amounts of proanthocyanidins, whereas the perennial S. drummondii releases mostly proanthocyanidins. Types and amount of allelochemicals exuded seem related to ecology and life history traits of each species. We then showed mobilisation of these allelochemicals by histochemical sections in imbibing seeds of both species. Histological structure is similar in both species. A number of characters (lens, subhilar parenchyma, tracheid bar) appear to function together to facilitate the exudation of compounds that protect young seedlings. Furthermore, the spatial organization of these organs with interlocking function allows retrieval of defensive substances stored in the seed, and their redeployment is beneficial for seedling survival. We hypothesize that optimisation of the chemical defences allocated to the seed by the maternal parent confers a significant advantage to the seedling, whose energy is mainly committed to growth.
Developing seeds of Sesbania drummondii are attacked by nymphs and adults of the bug Hyalymenus t... more Developing seeds of Sesbania drummondii are attacked by nymphs and adults of the bug Hyalymenus tarsatus (Heteroptera: Alydidae), which kill some seeds and weaken others. Parasitism by this piercing-sucking insect reduced the resources for the future seedling and affected seed physiology, including dormancy and exudation of allelochemicals of imbibing seeds. Seeds attacked by H. tarsatus had reduced mass (20-80% reduction, depending on intensity of attack). Heavy attack led to irregular shape, changes in seed coat color, and disruption of dormancy. While intact seeds did not imbibe during a 48-hour test in water, a high proportion of bug-attacked seeds germinated, from 51 to 94%, depending on intensity of attack. Attack by H. tarsatus also affected accumulation of allelochemicals and their exudation by imbibing seeds. There were no quantitative differences in proanthocyanidin content between exudates of attacked and unattacked seeds. In contrast, concentrations of total condensed ta...
Chemoecology, 1998
... Lilian Ceballos1,2, Martine Hossaert-McKey2, Doyle McKey1,3 and Claude Andary2 ... American s... more ... Lilian Ceballos1,2, Martine Hossaert-McKey2, Doyle McKey1,3 and Claude Andary2 ... American species of Sesbania that present contrasts in several ecological and life history traits: Sesbania 6esicaria (Jacq.) Ell., an annual species, and S. drummondii (Rydb.) Cory, a perennial ...
Acta Botanica Gallica, 2001