Effect of storage duration and temperature on seed germination of Plantago ovata L., P. indica L. and Lepidium sativum L (Asalio)

A study was carried out at ICAR-Directorate of Medicinal and Aromatic Plants Research (DMAPR) with an objective to evaluate seed germination of three very important medicinal species viz. Plantago ovata L, P. indica L., and Lepidium sativum L (Asalio) for standardizing eff icient germination procedure and to determine minimum seed standards. In the study, effect of different temperatures (15, 20, 25 and 30°C) and storage duration from 7 months to 3 years old seeds was evaluated including freshly harvested seeds on germination. Results revealed that seed germination was >95% at 20°C in 7 months old seeds of all the species. However, it varied with storage duration with time taken for germination i.e. first count and final count was on 2^nd and 6^th day, respectively at 20°C. Seed germination more than 80% could also be recorded up to a storage limit of 24 months excluding first three months after the harvest. Among the species, P. indica exhibited decreased germination after this storage duration at 20°C, while, >95% of seed germination could be recorded in 7–8 months old seeds after harvest in all the species irrespective of temperatures indicating that there was physiological dormancy initially in these species. Results also revealed that data on storage-dependent changes in seed germination and their responsiveness to temperature of Isabgol species and L. sativum are of potential implication for propagation of these plant species.