Effects of water salinity on germination and early seedling growth of untreated and pelleted sugar beet seeds (<em>Beta vulgaris</em> L.)

Abstract

Salinity is a serious abiotic stress factor as it restricts growth of many field crops, especially in the arid and semi-arid areas of the world. In this study, the effects of salinity stress on germination and early seedling growth of sugar beet seeds of different cultivars and breeding lines under labo­ratory conditions are investigated. Untreated and pelleted seeds of two sugar beet cultivars and five breeding lines were germinated at six salinity levels. The salinity levels were defined by electrical conductivity (EC): distilled water (~0 dS/m), and NaCl solutions of 2, 4, 6, 8, and 10 dS/m. In general, the results indicated that the salinity levels did not affect final germination percentage, but affected significantly emergence percentage, mean germination time and seedling fresh weight compared to control (~0 dS/m). Seedling emergence percentage was significantly reduced at salinity level 10 dS/m. Seedling fresh weight was significantly enhanced by all salinity levels compared to control. Mean germination time was delayed significantly due to increasing salinity levels. Under field growth condition, reduced emergence may affect the ability of the plants to compete for space, water and nutrients with weeds, or prolongs the time of vulnerability to pests and diseases. Therefore, it is recommended that besides the overall salinity resistance, seedling emergence under salt stress should be considered in breeding programs.