Integrated management of diseases and pests on ornamental geophytes: challenges and progress

Detection and Molecular Phylogenetic-Morphometric Characterization of Rhizoctonia tuliparum, Causal Agent of Gray Bulb Rot of Tulips and Bulbous Iris

“…Thus, although the ITS (ITS-5.8S-ITS2) primary sequences of all the three isolates of Rtul formed a well-supported clade in the phylogenetic tree (Figure 6), molecular morphometric analyses clearly differentiated them as three potentially distinct sexual species within R. tuliparum, sensu lato, per Müller et al [45] and Wolf et al [31] (Figure 8; Table S4), and call for further investigation. Moreover, from disease epidemiology and management viewpoints, our findings call for accurate identification of pathogen genotypes as well as determination of sensitivities of genetically diverse isolates of Rhizoctonia pathogens to commonly used fungicides [13,43,[47][48][49][50].…”

“…Currently, there are no reliable and rapid assay methods to assess inoculum levels of Rtul in the soil and on infected bulbs [11][12][13]. The ability to quantify inoculum levels of Rtul in the soil and on planting stock, coupled with information on inoculum threshold levels necessary for disease development, may allow for the development of predictive diagnostic tests to identify high-risk fields and planting stocks where inoculum of this pathogen is above threshold values [14][15][16][17].…”

“…The ability to quantify inoculum levels of Rtul in the soil and on planting stock, coupled with information on inoculum threshold levels necessary for disease development, may allow for the development of predictive diagnostic tests to identify high-risk fields and planting stocks where inoculum of this pathogen is above threshold values [14][15][16][17]. Access to this type of information would assist growers in making management decisions relating to the application of chemical or other control measures and potentially reduce the use of fungicides in the production of tulips and iris [13]. Therefore, we developed a sensitive and specific quantitative PCR (qPCR) assay [18] to detect Rtul and tested its effectiveness with bulb and soil samples.…”

Root-Associated Microbiomes, Growth and Health of Ornamental Geophytes Treated with Commercial Plant Growth-Promoting Products

“…Ornamental geophytes include some of the most desirable cut-flower varieties in the industry [ 1 , 2 ]. Geophyte producers suffer significant losses due to soil-borne diseases, as well as bacterial soft rot disease caused by pathogens from the genus Pectobacterium , which macerate the plant tissue after they penetrate it and can spread rapidly through the whole plant [ 3 , 4 ]. Strict sanitation measures, as well as soil treatments with chemical compounds, have allowed the international trade in ornamental geophytes to flourish.…”