Seed priming: state of the art and new perspectives.

Priming applied to commercial seed lots is widely used by seed technologists to enhance seed vigour in terms of germination potential and increased stress tolerance. Priming can be also valuable to seed bank operators who need improved protocols of ex situ conservation of germplasm collections (crop and native species). Depending on plant species, seed morphology and physiology, different priming treatments can be applied, all of them triggering the so-called 'pre-germinative metabolism'. This physiological process takes place during early seed imbibition and includes the seed repair response (activation of DNA repair pathways and antioxidant mechanisms), essential to preserve genome integrity, ensuring proper germination and seedling development. The review provides an overview of priming technology, describing the range of physical-chemical and biological treatments currently available. Optimised priming protocols can be designed using the 'hydrotime concept' analysis which provides the theoretical bases for assessing the relationship between water potential and germination rate. Despite the efforts so far reported to further improve seed priming, novel ideas and cutting-edge investigations need to be brought into this technological sector of agri-seed industry. Multidisciplinary translational research combining digital, bioinformatic and molecular tools will significantly contribute to expand the range of priming applications to other relevant commercial sectors, e.g. the native seed market.

The effectiveness of drug education programs: a critical review.

Twenty-seven studies were reviewed to determine whether school-based drug abuse prevention efforts have succeeded. Most of the studies reviewed either did not examine program impact on actual drug using behavior or were not designed with a degree of scientific rigor sufficient to warrant acceptance of their findings as valid. Those studies leading to reliable results regarding program effect on drug use were contradictory in their conclusions. In view of the possibility that educational efforts aimed at drug abuse prevention may be counterproductive, it is suggested that school-based programs henceforward be designed and conducted as experiments with controlled manipulation of relevant variables.