Influence of priming methods on seed germinability and transplants performance in six vegetable species

Seed priming is the induction of a particular physiological state in plants by the treatment of natural and synthetic compounds to the seeds before germination, with the aim to boost germination percentage and seedlings performance. The aim of the current research was to assess the influence of three seed priming treatments (control, cold priming and osmo priming) on the total germination percentage and the transplant quality of six vegetable species (artichoke [Cynara scolymus L.], endive [Cichorium endivia L.], fennel [Foeniculum vulgare L.], onion [Allium cepa L.], pepper [Capsicum annuum L.] and tomato [Solanum lycopersicum L.]). The transplants performance was compared in terms of biometric measurements and pigments (chlorophyll and carotenoids). Our results demonstrated that the positive effect of seed priming on total germination was species-dependent. Cold priming makes Cynara scolymus L. seeds reach 65% germination, Cichorium endivia L. seeds 93%, and Allium cepa L. seeds 81%. The osmo priming treatment brings the germination of Capsicum annuum L. seeds to 87%, and the Solanum lycopersicum L. seeds to 83%. Foeniculum vulgare seeds show the highest germination capacity compared to other tested species. Even the morphological traits of the six vegetable transplants were also influenced by the two priming methods in a specific-species manner. Osmo priming increased the total phenols content in Cichorium endivia L. and Solanum lycopersicum L. Finally, In Allium cepa L. both priming treatments reduced chlorophyll b and total chlorophyll content.