Germination and Early Seedling Growth Characteristics of Arachis hypogaea L. under Salinity (NaCl) Stress

Peanut plants (Arachis hypogaea L.) are glycophytes indicating their vulnerability to highly saline soils.The aim of this study was to evaluate the effect of different NaCl concentrations on seed germination characteristics and early seedling growth of peanut seeds of three Bulgarian cultivars -'Kremena', 'Kalina' and '4389'.Four different concentrations of NaCl (50, 100, 150 and 200 mM) were used as treatments and deionized water as control.To determine the salinity tolerance, the data for following germination characteristics -germination energy (%), final germination (%), coefficient of velocity of germination (% day -1 ), germination rate index and mean germination time (day) and seedling characteristics -shoot and root length (cm), fresh weight (mg plant -1 ) of shoot and root and dry weight (mg plant -1 ) of shoot and root were recorded.The Vigor index, coefficients of depression of roots and shoots and salt tolerance index were also calculated.The genotype had the strongest influence on the variance of the root length, while the salinity treatment had the strongest influence on germination energy, coefficient of velocity of germination, germination rate index, mean germination time, length of shoot, fresh weight of shoot and dry weigth of shoot and root.'Kremena' was the most tolerant at seedling growth stage, while '4389' was the most sensitive especially at high levels of salt stress.Principal component (PC) analysis grouped analysed cultivars at different salinity stress according to similarity on the basis of investigated germination and seedling characters in two components in the factor plane.