The present investigation was undertaken to improve the performance of carob
cuttings in terms of adventitious roots formation and hardening using
arbuscular mycorrhizal fungi (AMF). Softwood cuttings were treated with 5000
mg L-1 of indole-3-butyric acid (IBA) and kept noninoculated (Non-AM) or
inoculated with Funneliformis mosseae (Fmo) alone or combined with
Rhizophagus fasciculatus (Fmo+Rfa) or R. intraradices (Fmo+Rin) or both
(Fmo+Rfa+Rin) and then maintained under mist conditions. After two months,
rooted cuttings were transplanted on sterilized substrate and transferred to
a hardening greenhouse for five months. Obtained results showed that
inoculation of the rooting substrate with AMF substantially improved the
percentage of rooted cuttings and the number of roots per cutting. The
highest rooting (63.33%) and number of roots per cutting (11.67) were
recorded in the presence of the complex of the three AMF strains
(Fmo+Rfa+Rin). Moreover, all mycorrhizal-rooted cuttings survived
transplantation and hardening shocks and showed the highest growth and
physiological performances. Indeed, in the Fmo-Rfa-Rin-plantlets the gains in
plant height and shoot and root dry weights were 95.6%, 55.1% and 76.9%
respectively. Furthermore, stomatal conductance, total chlorophyll content,
photochemical efficiency of PSII (Fv/Fm) and nutrient concentrations were
higher in mycorrhizal plantlets than in non-AM ones. Thus, AMF substantially
improved carob cuttings? performance in terms of rooting capacity and
hardening efficiency, thereby increasing the potential of carob propagation
by cuttings.
Improved rooting capacity and hardening efficiency of carob (Ceratonia siliqua L.) cuttings using arbuscular mycorrhizal fungi
