OPTIMIZING MICRO PROPAGATION OF Asparagus officinalis AND STIMULATING PLANTLETS USING ARBUSCULAR MYCORRHIZAL FUNGI

Abstract

The study aimed to optimize the micropropagation process, including seed sterilization, shoot multiplication and in vitro rooting and to investigate the effect of arbuscular mycorrhizal fungi (AMF) inocula on the stimulation of the plantlets (Asparagus officinalis) growth. The results showed that the highest germination rate was 90% when the seeds were disinfected with 6% sodium hypochlorite for 10 minutes. A Murashige and Skoog medium (MS) supplemented with 2.0 mg/L kinetin and 0.1 mg/L naphtalen-acetic acid effectively promoted the shoot formation with 6.6 shoots/explant and shoot length reaching 6.24 cm. Shoots cultured on semi-MS supplemented with 0.7 mg/L indole-3-butyric acid gained the best rooting rate of 42.67%, an average of 3.73 roots/plant, root length reaching 3.93 cm and no callus formation. The plantlets treated with each of three different AMF inocula grew better and achieved a 100% survival rate. Among them, the treatments amended with either AMF-SA or AMF-SC inoculum recorded the highest performance, with an average of 13.6 and 13.2 stems and plant heights of 66.38 and 66.26 cm, respectively. The combination of the micropropagation and AMF improved the propagation efficiency and growth performance of the asparagus in the plantlet stage.