BACKGROUND Plant species have several mechanisms to avoid selfing such as dichogamy or a self-incompatibility response. Dichogamy in a single flower may reduce autogamy but, to avoid geitonogamy, plants must show flowering synchronization among all their flowers (i.e. synchronous dichogamy). It is hypothesized that one species would not simultaneously show synchronous dichogamy and self-incompa...

BACKGROUND AND AIMS Although pollen limitation of reproduction (PL) has been widely studied, our understanding of its occurrence in tropical communities, especially for bird-pollinated plants, is underdeveloped. In addition, inclusion of both quantity and quality aspects in studies of PL are generally lacking. Within hummingbird-pollinated plants, a prediction was made for higher PL for the qua...

The presence of Ursinia nana, an Anthemideae of South-African origin which has been introduced into the NE Iberian Peninsula, is reported for the fi rst time in Europe. The data offered cover its precise location, morphology, chromosome number, ecology and a population census, as well as its life cycle, fl oral structure, reproductive biology and fruit dispersal mechanisms. Of special note are ...

The clonal age in paramecia refers to the total number of vegetative divisions a clone has undergone since its origin at autogamy (self-fertilization). As clonal age increases, the interfission time usually increases. The DNA synthesis pattern of cells of different ages was compared by autoradiographic analysis of the DNA synthesis of synchronized cells at various time intervals during the cell...

The fitness of self-progeny individuals is inferior to that their outcrossed counterparts, resulting in a reduction plant population’s ability survive and reproduce. To prevent self‐fertilization, angiosperms with hermaphrodite flowers may exploit variety mechanisms, including synchronous dichogamy self-incompatibility. Synchronous involves two flowering morphs, strict within-morph synchronizat...

Ackonwledgements This work presented here was down at the Centre de Génétique Moléculair, CNRS under the supervision of Dr.Jean COHEN. Foremost, I would like to express my deepest appreciation to my advisor Dr. Jean COHEN for the continuous support for my thesis throughout my studies in France. In particular, I am grateful to Madam France KOLL for her comments on the thesis and precious suggest...