Laser Light Stimulation Effects on Scorzonera hispanica L. Seeds Germination, Field Emergence and Photosynthetic Pigments Content

Abstract

The study presented herein concerns the effect of pre-sowing stimulation of scorzonera seeds with He-Ne laser on germination capacity, field emergence of seedlings and the content of chlorophylls and carotenoids. Seeds of scorzonera cv. 'Duplex', from harvests of various years, dis-played variable quality expressed by their germination capacity. They were subjected to pre-sowing stimulation with He-Ne laser light of the power of 40 mW and wavelength of 632.8 nm, surface power density of 5 mW·cm-2 and different exposure times. Germination capacity on Petri dish test increased only in one lot of seeds after exposure for 1 and 5 min. Increase in seedling emergence in the field experiment in the result of laser treatment occurred only in one seed lot. One-min laser treatment increased contents of chlorophylls and carotenoids in 8-day cotyledons (laboratory test) and in the second true leaves (field experiment).