Assessment of genetic fidelity, biochemical and physiological characteristics of in vitro grown date palm cv. Al-Fayda

Abstract

The effects of various culture conditions on adventitious bud multiplication and plantlet regeneration in date palm cv. Al-Fayda were investigated. Adventitious buds were cultured on semi-solid Murashige and Skoog (MS) medium supplemented with three different plant growth regulator (PGR) combinations. The effects of various strengths and textures of the multiplication medium were evaluated and the adventitious buds were cultured on media supplemented with various types and concentrations of carbon sources. It was found that semi-solid 1/2MS medium supplemented with 2.4 µM NOA, 2.3 µM KIN and 40 g l−1 sucrose is the most effective for shoot bud multiplication with 30 shoot buds per explant. On the other hand, liquid media resulted in very high levels of hyperhydricity (up to 100%). Peroxidase activity ranged from 372 to 709 U g−1 FW and was higher in buds cultured on liquid media, while the total protein concentration ranged from 16.3 to 46.7 mg g−1 FW. Shoot elongation and rooting were successfully achieved on semi-solid 1/2MS medium supplemented with 2.4 µM NOA, 2.3 µM KIN and 40 g l−1 sucrose. Regarding the physiological characteristics of developed shoots, the chlorophyll content ranged from 6.50 to 14.40 CCI, the chlorophyll fluorescence from 0.682 to 0.750, the foliar surface from 6.85 to 9.88 cm2 and the stomatal conductance from 8.97 to 12.51 mmol m−2 s−1. The rooted plantlets were successfully acclimatized in the glasshouse with a survival rate of 70%. The genetic conformity of regenerants was assessed by inter-simple sequence repeat (ISSR) markers, and a high similarity with the mother plant was observed.