Response to Direct Selection against Drought Stress in Black Cumin (Nigella sativa L.)

Abstract

Central Anatolia is prone to drought with low precipitation and high evapotranspiration which influence the growth of a several crops. The selection and cultivation of drought-tolerant crops that can survive and maintain under poor climatic conditions are very important. Black cumin (Nigella sativa L. Umbelliferae) is famous for aromatic, medicinal, and therapeutic uses in the Mediterranean region and elsewhere. Drought stress most often delays or reduces seed germination ending up in irregular and poor crop growth. The study aimed to compare the effects of −0.1, −0.2, and −0.4 MPa of PEG 6000 osmo-priming pretreatments for 12, 24, and 36 h and two PEG 6000 post-treatments of −0.05 and −0.15 MPa along with their respective controls for 14 days as post-treatment on seed germination and seedling establishment potential of Turkish cv. Cameli. The results showed significant differences among germination index, germination stresses tolerance index, germination speed, final germination percentage, seedling vigor index, mean germination time, shoot, root and seedling length, and seedling fresh and dry weight of pretreatments and post-treatments when compared to nonprimed and hydro-primed seeds used as control treatments. Osmo-priming pretreatments of black cumin using −0.2 or −0.4 MPa PEG 6000 for 24 or 36 hours in a medium containing −0.05 MPa PEG 6000 as post-treatment showed improved germination efficiency, with increased adaptation ability.