First records of powdery mildew fungi (Erysiphales) on medicinal plants in Taiwan

Abstract

Background Production of medicinal plants in Taiwan is not only hampered by international market competition, but also lack of knowledge of their pathogens, such as powdery mildew fungi (Erysiphales, Ascomycota). Records of these fungi in Taiwan originate from few researchers for the last one hundred years and are still incomplete. Since powdery mildews in tropical/subtropical environments rarely develop the sexual stages with morphologically diagnostic characteristics, internal transcribed spacer sequences (ITS) of the ribosomal RNA genes obtained from the asexual stages have become important modern tools for species identification. Results Powdery mildews on medicinal plants from educational and ornamental plantations in Taiwan were identified based on the anamorph morphology and ITS sequences. Four powdery mildews on medicinal plants are new records for Taiwan, Arthrocladiella mougeotii on Lycium chinense, Erysiphe glycines on Pueraria lobata, Erysiphe lespedezae on Bauhinia sp., Desmodium caudatum, and Uraria crinita, and E. lonicerae on Lonicera japonica. Eryngium foetidum is a new host for Erysiphe heraclei hitherto known on other host plants in Taiwan. Eryngium foetidum and Uraria crinita are new host plants for powdery mildews worldwide. Only specific field collection of the pathogens yielded the new records, not checking plant specimens in a phanerogam herbarium. The pathogens did not cause death of the host plants, but appeared to enhance stress by infection of mature leaves. Conclusions Taxonomic study of powdery mildews in Taiwan results into new host records of economically important medicinal plants in Taiwan with potential consequences for plant production and quarantine and also shows that host records are quite incomplete worldwide. Although ITS sequences were useful for species identification, the lack of data for several species on the same host genus on the one hand and the low variation between closely related species on the other indicate the need for further study.

New Records of Powdery Mildews from Taiwan: Erysiphe ipomoeae comb. nov., E. aff. betae on Buckwheat, and E. neolycopersici comb. nov. on Cardiospermum halicacabum

“…In the present study, the occurrence periods of the PMs in the winter and spring imply they prefer mild weather instead of excessively high temperature (up to 35 • C) in summer, and it is suggested that the PMs in the subtropical regions may stay in a quiescent state in their hosts during hot summers. However, chasmothecia are rarely formed in subtropical and tropical environments [23,47,77,94]. Thus, the reservoirs of the PMs on all their possible hosts as mycelia or other structures are crucial for their survival and for the infection in the next season.…”

“…Subsequent studies related to this group of PMs in Taiwan can be referred in Kuo [15], Braun and Cook [2], and the List of Plant Diseases in Taiwan [16]. Additional investigations in recent years are those in Kirschner and Liu [17], Kirschner [18], Wang et al [19][20][21], Kirschner et al [22], Yeh et al [23], and Xiao et al [24].…”

Antimicrobial Peptides and Their Applications in Biomedical Sector

“…The smallest AMPs were derived from jatropha curcas with seven amino acids [ 192 ]. Commonly found AMPs in plants are the cyclotide family, thionins, the α-Hairpinin family, Hevein-like peptides, lipid transfer protein, knottin-type peptides, snakins, and plant defensins [ 193 ]. Thionin is a useful AMP for the development of a glucose detection biosensor.…”