A new potential seed vigour test for pepper: excess water stress (EWS)

Seed vigour tests are used to predict relative seedling emergence performance and seed storage tolerance, but a valid or universal test for all crops is still unattainable. Therefore, new approaches to testing seed vigour need to be explored. This study investigated the possibility of using excess water stress (EWS) in predicting the emergence performance of pepper seed lots. Twelve seed lots of pepper were subjected to different vigour tests, including electrical conductivity (EC), cool (CT), accelerated ageing (AA) and 3-fold and 5-fold EWS tests in which the seeds were germinated under excess water. The results indicated that germination percentage (GP) varied from 54.5% to 89.5% in the AA test, whereas it varied between 16.5% and 93% in the CT. In 3-fold EWS, GP ranged from 53 to 93.5% and from 54 to 93% in 5-fold EWS. The correlation coefficient between GP and emergence percentage (EP) was r = 0.610 ( p < 0.05), while EP correlated with GP in AA ( r = 0.814, ( p < 0.01)) and CT ( r = 0.736, ( p < 0.01)). The highest correlations were found for EP in 5-fold EWS with r = 0.864, ( p < 0.01), followed by 3-fold EWS with r = 0.827, ( p < 0.01). These results suggest that EWS can estimate the seedling emergence more accurately and should be considered a promising predictor of EP in pepper.