Breaking Seed Dormancy in Wild Lentil Species Using an Abscisic Acid Antagonist to Explore and Utilize Wild Relatives as Genetic Resources

Wild lentil genotypes are a valuable resource for genetic diversity, but their scientific study and utilization in breeding programs have been hampered by traits such as crossability barriers and seed dormancy. To make wild lentil genotypes more accessible for further exploration, we investigated the effect of different seed scarification techniques plus the abscisic acid (ABA) analog, ABA-1019 on breaking dormancy and seed germination release in seven lentil genotypes and 54 accessions (lines). Dormancy was alleviated by scarification with or without the addition of chemical substances but germination release was dependent on lentil genotypes/accessions and seed coat manipulations. ABA-1019 functions as an antagonist to native ABA, thereby blocking the ABA-induced delay in germination. ABA-1019 significantly increased germination and seedling emergence rates compared to the water and dimethyl sulfoxide (DMSO) controls. DMSO increased germination rates and indices in some lentil genotypes compared to water control. ABA-1019 also had a positive effect on shortening the time to germination, emergence, and flowering, which is of particular interest when developing inbred populations or advancing lines to increase homogeneity. Our results indicate that combinational (physical and physiological) dormancy exist in some lentil accessions.