Occurrence of Stem and Leaf Spots on Lucky Bamboo (Dracaena sanderiana hort. ex. mast.) Plants in Vase and its Cure with Safe Means

Abstract

Lucky bamboo (Dracaena sanderiana) plants showing stem and leaf spots symptoms of each observed season were monitored during a survey that was conducted in four periods from 2018 to 2019. There were significant differences between the four periods, as well as the mean percentages of infection and disease severity were high (45.92, 44.41 % and 46.15, 55.67%, respectively) During the first (March-May) and third (August-October) study periods in 2018. The same disease symptoms occurred at the same time of observation during 2019 in the several surveyed nurseries, and the percentage of infection and disease severity recorded were in the same trend. There were twelve different fungal pathogens identified as Absidia spinosa, A. Cylindrospora, Alternaria alternata, Aspergillus flavus, A. niger, A. terreus,Aspergillus sp., Colletotrichum gloeosporioides, Fusarium avenaceum, F. oxysporum, F. solani, and Trichoderma harzianum where Colletotrichum gloeosporioides was the most common (26.93 and 26.34 for leaves and stems, respectively). The pathogenicity tests were carried out, where C. gloeosporioides were the most aggressive. The systemic fungicide Kemazed® and biocontrol agents were demonstrated to be effective in controlling three of the most common aggressive fungi. i.e., C. gloesporioides, F. Oxysporum and A. alternata, In vitro colony growth of fungal isolates was significantly reduced as compared to the untreated control. The bioagents tested had significant antagonistic activity against C. gloesporioides growth on bamboo in a vase, according to the results, with Kemazed® showing the most consistent highest inhibition effect, followed by Rhizo-N®and Plant Guard®, respectively, when compared to the untreated control.