Germination profiling of lentil genotypes subjected to salinity stress.

Salinity is one of the most severe environmental stresses, negatively affecting productivity of salt-sensitive crop species. Given that germination is the most critical phase in the plant life cycle, the present study aimed to determine seed germination potential and associated traits under salt stress conditions as a simple approach to identify salt-tolerant lentil genotypes. The genetic material consisted of six lentil genotypes whose adaptation to various agroclimatic conditions is not well elucidated. Salinity stress was applied by addition of NaCl at three different levels of stress, while non-stressed plants were included as controls. Evaluation of tolerance was performed on the basis of germination percentage, seed water absorbance, root and shoot length, seedling water content, seedling vigour index and number of seedlings with an abnormal phenotype. Overall, our findings revealed that salinity stress substantially affects all traits associated with germination and early seedling growth, with the effect of salinity being dependent on the level of stress applied. It is noteworthy, however, that genotypes responded differently to the varying salinity levels. In this context, Samos proved the most salt-tolerant genotype, indicating its possible use for cultivation under stress conditions. In conclusion, the determination of seed germination and early growth potential may be exploited as an efficient strategy to reveal genetic variation in lentil germplasm of unknown tolerance to salinity stress. This approach allows selection of desirable genotypes at early growth stages, thus enabling more efficient application of various breeding methods to achieve stress-tolerant lentil genotypes.

Influence of storage conditions on protein profile of pepper seeds, analyzed by SDS-PAGE.

Seeds were stored under variable conditions for long or short periods of time at 5 degrees C or 25 degrees C after which they were germinated and total proteins were analyzed by SDS-PAGE. An 80 KDa protein was expressed only in the seeds that had been recently harvested (1 year storage period). A protein of 60 KDa was detected in much higher amounts in the seeds harvested in 1987 and stored at 5 degrees C for 14 years, as well as in seeds harvested in 2000 compared with the seeds harvested in 1989 and stored at 25 degrees C for 12 years. A 50 KDa protein was present in the seeds harvested in 1987 and stored at 5 degrees C, as well as in the seeds harvested in 2000 but not in the seeds harvested in 1989 and stored at 25 degrees C. It is proposed that SDS-PAGE can be used to identify proteins in germinating pepper seeds, that vary with the storage conditions. Such information could be of value for seed control and the evaluation of seed vigour.