We evaluated the effects of various plant growth regulator (PGR) combinations on adventitious shoot bud multiplication of date palm cv. Aziza Bouzid. In the first experiment, we assessed the effect of four PGR combinations that have already shown good results in other date palm cultivars: half-strength Murashige and Skoog medium (MS/2) supplemented with 0.5 mg/L 2-naphthoxyacetic acid (NOA) and 0.5 mg/L kinetin (KIN); MS/2 supplemented with 0.2 mg/L NOA, 0.2 mg/L indole-3-acetic acid (IAA), 0.4 mg/L 6-(dimethylallylamino)purine (2iP) and 0.4 mg/L KIN; MS/2 supplemented with 0.5 mg/L 1-naphthaleneacetic acid (NAA) and 0.5 mg/L KIN and finally MS/2 supplemented with 0.5 mg/L indole-3-butyric acid (IBA) and 0.6 mg/L 6-benzylaminopurine (BAP). Our results showed no significant difference among the four culture media in terms of adventitious shoot bud multiplication (26.7-28.4 adventitious buds per explant). However, the medium containing 0.5 mg/L NOA and 0.5 mg/L KIN showed significantly lower rate of precocious rooting and thus this auxin-cytokinin combination was chosen for the second experiment. In the second experiment, we evaluated the effects of various NOA and KIN concentrations on adventitious shoot bud multiplication: 0, 0.25, 0.5 and 1 mg/L of each PGR, either alone or in combination. It was found that the combination of 0.5 mg/L NOA and 0.5 mg/L KIN is still the most appropriate for adventitious shoot bud multiplication. Shoot elongation and rooting were achieved on PGR-free MS/2 medium and a high acclimatization rate of 70% was observed in the greenhouse.
The effects of medium strength as well as different antioxidant types and concentrations on adventitious shoot bud multiplication, hyperhydricity and tissue browning of date palm cv. Aziza Bouzid were evaluated. Organogenic cultures of date palm cv. Aziza Bouzid were cultured on semi-solid Murashige and Skoog medium at half-strength (MS/2) or onethird-strength (MS/3), supplemented with 0.5 mg/L 2-naphthoxyacetic acid (NOA), 0.5 mg/L kinetin, and different concentrations of activated charcoal and polyvinylpyrrolidone (PVP). The findings of the present study showed that the use MS/3 media resulted in lower hyperhydricity rates than MS/2 media. Besides, activated charcoal significantly reduced tissue browning. The lowest rates of hyperhydricity (35%) and tissue browning (20%) were observed in MS/3 medium supplemented with 1.5 g/L activated charcoal. Interestingly, this culture medium showed also the highest number of adventitious shoot buds per explant (35.20), with a significant difference with all the other media (25.55-30.15 adventitious shoot buds per explant). Increasing the concentration of activated charcoal to 2 g/L did not decreased the browning rate. The use of PVP alone showed tissue browning rates varying from 30 to 55% while combining PVP and activated charcoal showed browning percentages ranging from 20 to 30%. Shoot elongation and rooting were successfully achieved and plantlet were acclimatized and showed normal growth and development under the greenhouse conditions.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.