A collection of 130 olive samples, originating from diverse areas in Europe and corresponding to 67 different cultivars denominations, was genotyped at 14 microsatellite loci. In total, 135 alleles with a mean number of 9.6 alleles per locus were detected. All but 30 accessions showed unique genotypes. Several cases of synonymy listed in the FAO database of olive germplasm could not be confirmed, as different allelic profiles were obtained from putatively synonymous cultivars. The existence of homonyms or mislabeled samples in olive germplasm collections was evidenced by allele differences of up to 60% between samples of the same denomination. An allele-sharing phenogram of the analyzed genotypes revealed several cultivars with high levels of intra-varietal polymorphism, as well as cultivar families consisting of closely related cultivars with similar denominations. Our work shows that the current designations of olive cultivars fall short of describing the genetic variability among economically important plant material. A thorough investigation of the existing variability will prove of major importance for both management and economic production of olive trees.

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Maize coenocytic and cellularizing endosperm development were characterized at optical and transmission electron microscopy levels. Samples were collected daily in 3 consecutive years under different temperature regimes; therefore, the developmental stages were expressed on a growing degree basis. Soon after the primary endosperm nucleus is formed, it starts dividing without cytokinesis, leading to the formation of the coenocyte. The nuclei divide freely on the periphery of the coenocyte and spread from the micropylar region toward the chalazal region. The first anticlinal walls are formed as the nuclei come closer to each other, followed by periclinal wall formation also starting in the micropylar region. As cellularization proceeds, new anticlinal and periclinal walls assume a less organized pattern until the central vacuole is fully occupied by newly formed cells. Overall, our findings suggest that the developmental pattern of maize coenocytic and cellularizing endosperm has many similarities to other species of the Poaceae family.

The identification of microsatellite loci in Rubus hochstetterorum provides an important tool for the characterization and conservation of wild populations of this species. Crossspecies amplification of markers may be of particular interest for the study of other Rubus species. In this study, 41 simple sequence repeat markers were identified in a genomic library of R. hochstetterorum . Fifteen of the identified microsatellite loci were characterized in a set of 30 samples and revealed to be polymorphic with three to 19 alleles per locus. All the identified markers allowed cross-species amplification in at least one of the other three tested species from the Rosaceae family.

This study reports 19 simple sequence repeat loci developed from a genomic library of the olive tree ( Olea europaea L.), of which 12 revealed to be polymorphic and informative, ranging from two to 14 alleles.