Micropropagation of zaghlol and barhy date palm cultivars using immature female inflorescence explants : effect of growth regulators balance

الملخص EN

The present study aimed to micropropagate two date palm cultivars (Zaghlol and Barhy) using immature female inflorescence and various growth regulators combinations.

This experiment was done in Biotechnology Laboratory, Department of Genetics, Faculty of Agriculture Zagazig University, during three consecutive seasons 2017, 2018, and 2019.

Three types of culture media were used for initiation stage, results showed that initiation medium1 (1.0 mg /l 1-Naphthaleneacetic acid (NAA) + 0.1 mg Indole-3-acetic acid (IAA) + 1.0 mg /l 2, 4-Dichlorophenoxyacetic acid (2, 4-D)) was the best medium that recorded the highest callus formation rate in both Zaghlol and Barhy cultivars.

But the Barhy cultivar showed higher response for callus formation than Zaghlol cultivar, especially for number of days to initiate callus (average mean 125.58 days compare to 279 days for Barhy and Zaghlol, respectively.

For plant regeneration stage, it was used three plant regeneration media.

Results showed that plant regeneration medium 1 (NAA 0.5 mg/l +benzyl adenine (BA) 2.0 mg/l) showed the best value for each of number of leaves (19.35), leaf length (39.75 cm) and number of days to initiate regeneration (19).

Two types of rooting media were used for root formation, it was found that rooting medium 1 (Indole-3-butyric acid (IBA) 2.0 mg/l + BA 2.0 mg/l) gave higher response than rooting medium 2 (NAA 2.0 mg/l +BA 2.0 mg/l) for almost measured criteria except root length.

Also, using rooting medium 1 decreased the number of days for root formation to 40 days compared to 110.25 days obtained from rooting medium 2.