Comparative anatomical study of date palm (Phoenix dactylifera L.) procallus Hilwaii cultivar produced by different plant auxins.

Abstract

The present study has been conducted to define any adverse consequences of different plant auxins including 2, 4-D; NAA and Dicamba on the cells of date palm procallus of Hillawii cv. Cross anatomical sections has been performed on procallus cells produced by these auxin treatments. Results revealed the significant damages which caused by 2, 4-D at high concentration (100 mg/ l), these damages were evident by dense distribution patterns of tannin compounds across the whole tissues.These patterns were accompanied with a severe and high percentage of browning (80 %) for examined procallus, compared with the same auxin at low concentration (50 mg/ l), which showed a restricted distribution pattern of tannin compounds beneath epidermal cells, hence, all the examined procallus of this treatment were healthy with no browning phenomenon, followed by the treatments of NAA and Dicamba. Additionally, our results explained that the treatment of 2, 4-D at high concentration (100 mg/ l) led to an evident histological change of examined procallus, the thickness of parenchyma tissue cells were increased, both length and width were reached the averages of 77 and 52 µm, respectively, this increase was accompanied with a reduction in the cell number which was 653 cells, compared with what were observed at low concentration of 2, 4-D (50 mg/ l) which reported the number of cells 671.5 cells, and a size of 57.5 and 42.5 µm, respectively. It's noteworthy that the treatment of 2, 4-D at 100 mg/ l led to reduce the thickness of epidermal cells which found to be 27.5 µm, in comparison with 37.5; 35 and 37.5 µm in 2, 4-D (50 mg/ l); NAA and Dicamba, respectively.