SALINITY TOLERANCE OF FRUIT TREES IN IN VITRO CONDITIONS [TOLERANCE SALINITY OVOCNÝCH DRUHŮ V IN VITRO PODMÍNKÁCH]

Abstract

Soil salinity or salinity is a worldwide problem that affects agricultural production. Most studies on salinity have focused on cereals and exotic crops, but there is a minimal amount of literature on pome and stone fruit trees. The salinity tolerance of selected pome, stone and small fruit trees was monitored under in vitro conditions at different concentrations of NaCl in multiplication medium for almost 1 year. The plants were observed for their habitus and the content of plant pigments was measured spectrophotometrically. In most cases, there was a decrease of plant pigments concentration with increasing salt content compared to the null variant (NaCL0 = 0 g/L NaCl). The most significant decrease occured in stone fruit trees in comparison of NaCl0 (on average 0.594 mg/g chlorophylls and 0.074 mg/g carotenoids) and the maximum concentration of NaCl5 (on average 0.142 mg/g chlorophylls and 0.033 carotenoids). The concentration of pigments also decreased with increasing salinity for most pome fruit trees. On average, it amounted 0.505 mg/g chlorophylls and 0.069 mg/g carotenoids, in the case of the NaCl5 it decreased to 0.0268 mg/g chlorophylls and 0.060 mg/g carotenoids. On the other hand, in ‘Erika’, the values of chlorophylls increased at concentration of NaCl7.5, and values of carotenoids fluctuated. Values decreased for small fruit trees (NaCl0: 0.457 mg/g chlorophylls and 0.078 mg/g carotenoids X NaCl5: 0.266 mg/g chlorophylls a 0.058 mg/g carotenoids). The exceptions were ‘Trnavská’ mulberry, honeysuckle ‘Zoluška’ and ziziphus ‘Gagadzao’, which showed an increase in the concentrations of pigments at the contration of NaCl2.5.

Keywords

• salinity tolerance
• in vitro
• chlorophylls
• carotenoids