A strong attention is recently paid to surface properties of building materials as these allows controlling solar gains of the building envelope and...
The recovery of inaperturate pollen from functionally female flowers in archaeological layers opens the question of a possible pollen-based discrimination between wild and domesticated Vitis vinifera in prehistoric times. Pollen analysis applied to archaeology has not routinely considered the existence of pollen dimorphism in Vitis, a well-known trait in the field of agrarian studies. Therefore, the inaperturate shape of grapevine pollen is ignored by studies on the archaeobotanical history of viticulture. In this paper we investigate pollen morphology of the domesticated and wild subspecies of V. vinifera, and report the first evidence of inaperturate Vitis pollen from an archaeological site. We studied exemplar cases of plants with hermaphroditic flowers, belonging to the subspecies vinifera with fully developed male and female organs, cases of dioecious plants with male or female flowers, belonging to the wild subspecies sylvestris and cases of V. vinifera subsp. vinifera with morphologically hermaphroditic but functionally female flowers. The pollen produced by hermaphroditic and male flowers is usually trizonocolporate; the pollen produced by female flowers is inaperturate. This paper reports on the inaperturate pollen of Vitis found in an archeological site of the Po Plain, Northern Italy. The site dated to the Bronze Age, which is known to have been a critical age for the use of this plant with a transition from wild to domesticated Vitis in central Mediterranean. Can the inaperturate Vitis pollen be a marker of wild Vitis vinifera in prehistoric times? Palynology suggests a possible new investigation strategy on the ancient history of the wild and cultivated grapevine. The pollen dimorphism also implies a different production and dispersal of pollen of the wild and the domesticated subspecies. Grapevine plants are palynologically different from the other Mediterranean “cultural trees”. In fact, Olea, Juglans and Castanea, which are included in the OJC index, have the same pollen morphology and the same pollen dispersal, in wild and domesticated plants. In contrast, the signal of Vitis pollen in past records may be different depending on the hermaphroditic or dioecious subspecies.
Quercus robur L. was micropropagated by axillary bud proliferation testing two different shoot culture systems: (i) on gelled medium in Microbox (plastic vessel with a strip for ventilation) and (ii) in liquid culture in PlantformTM bioreactor (a temporary immersion system). Two different conditions of temporary immersion were assessed: 12 min/8 h (Plantform 1) and 8 min/16 h (Plantform 2). The effect of the two culture systems was evaluated also during subsequent rooting phase, carried out on gelled medium. Finally, the influence of the different culture conditions on leaf structure was considered, taking also into consideration the micromorphological characters of young leaves from in-field-grown oaks. Nodal segments, excised from established in vitro shoots and cultured on modified Woody Plant Medium, showed a higher Relative Growth Rate in Plantform than in Microbox, but culture conditions provided in Plantform 1 favored shoot and leaf hyperhydricity. Shoots cultured in Microbox or Plantform 2 presented the same percentage of rooting after their transfer on gelled rooting medium. Leaves developed in the two different microenvironments had large stomata with elliptical shape, which indicates good functionality, and formed hairs, and epicuticolar waxes. These leaf features are considered to provide a good adaptability to ex vitro conditions.
10 December 2018 in Journal of Agricultural and Food Chemistry