MORPHOLOGICAL AND HISTO-ANATOMICAL STUDY OF ROOT SYSTEM OF DATE PALM (PHOENIX DACTYLIFERA L.) IN RELATIONSHIP WITH ARBUSCULAR MYCORRHIZAL SYMBIOSIS

H. Faidi, L. Bouhired
The objective of this study was to investigate a possible relationship between the morphology and histo-anatomy of root system of date palm and the establishment of mycorrhization. The experimental work was carried out on young seedlings grown from seeds of ‘Deglet Noor’ cultivar inoculated with the arbuscular mycorrhizal fungus Glomus fasciculatum. Periodic samples are performed at 1, 2, 4, 6, 7 and 9 months after transplantation. The morphological study of the root system is based on the model of Rose (1983). The roots samples were stained with trypan blue according to a modified version of the method described by Phillips and Hayman (1970). The rate of this infection is estimated using the method described by Trouvelot et al. (1986). The root sections were stained with methyl green and Congo red. From the third sampling (4 months after transplantation and inoculation), the presence is observed of two morphological types of lateral roots. In the first type, the roots, regardless of their order, have a constant diameter throughout their length, they are called “straight” roots. In the second type, some have an irregular diameter i.e., parts prominently thickened and thinned portions, other present a thickening along their length. In this second type, the roots are called “tuberized” roots. The mycorrhizal infection was higher and more constant in the roots called “tuberized”, particularly in their thickned part, in regard to the roots called “straight” which are weakly or not mycorrhized. The cortex of the thickened part of the tuberised roots is privileged site of the mycorrhizal infection. It is characterized by the total absence of sclerenchyma and aerenchyma. While the cortex of both the straight root and the thinned part of the tuberized roots have a ring of sclerenchyma and aerenchyma
Faidi, H. and Bouhired, L. 2013. MORPHOLOGICAL AND HISTO-ANATOMICAL STUDY OF ROOT SYSTEM OF DATE PALM (PHOENIX DACTYLIFERA L.) IN RELATIONSHIP WITH ARBUSCULAR MYCORRHIZAL SYMBIOSIS. Acta Hort. (ISHS) 994:193-203
http://www.actahort.org/books/994/994_18.htm
Glomus fasciculatum, straight roots, tuberized roots, pneumatodes
French

Acta Horticulturae