Molecular Phylogeny of the Plant Pathogenic Genus Botrytis and the Evolution of Host Specificity

Abstract

The cosmopolitan genus Botrytis contains 22 recognized species and one hybrid. The current classification is largely based on morphological characters and, to a minor extent, on physiology and host range. In this study, a classification of the genus was constructed based on DNA sequence data of three nuclear protein-coding genes (RPB2, G3PDH, and HSP60) and compared with the traditional classification. Sexual reproduction and the host range, important fitness traits, were traced in the tree and used for the identification of major evolutionary events during speciation. The phylogenetic analysis corroborated the classical species delineation. In addition, the hybrid status of B. allii (B. byssoidea x B. aclada) was confirmed. Both individual gene trees and combined trees show that the genus Botrytis can be divided into two clades, radiating after the separation of Botrytis from other Sclerotiniaceae genera. Clade 1 contains four species that all colonize exclusively eudicot hosts, whereas clade 2 contains 18 species that are pathogenic on either eudicot (3) or monocot (15) hosts. A comparison of Botrytis and angiosperm phylogenies shows that cospeciation of pathogens and their hosts have not occurred during their respective evolution. Rather, we propose that host shifts have occurred during Botrytis speciation, possibly by the acquisition of novel pathogenicity factors. Loss of sexual reproduction has occurred at least three times and is supposed to be a consequence of negative selection.

Chemical Composition of Celandine (<i>Chelidonium majus</i> L.) Extract and its Effects on <i>Botrytis tulipae</i> (Lib.) Lind Fungus and the Tulip

“…tulipae is the only Botrytis species able to infect tulip (Staats et al, 2005) and to abundantly produce sporulating gray mycelium on infected tissue (Yohalem et al, 2003). The mitotically produced spores, macroconidia, can be transported long distances by wind (Agrios, 2005;Webster and Weber, 2007).…”

“…The ability of B. tulipae to infect living host plants may result from a combination of at least 4 factors: (1) possession of pathogenic factors (e.g., toxins and cell-wall degrading enzymes) that confer the ability to kill and invade plant tissue; (2) the ability to avoid or counteract plant resistance mechanisms; (3) the ability to survive outside host-plant tissue under less favorable conditions (e.g., low humidity and UV irradiation); and (4) the ability to reproduce and disperse (Staats et al, 2005).…”

Botrytis cinerea is the causal agent of post-harvest grey mould rot on green bean (Phaseolus vulgaris) in Korea

“…1 Post-harvest grey mould rot on green bean. a Symptoms of post-harvest grey mould rot caused by Botrytis cinerea b grey mould rot developed 7 days after artificial inoculation c one-weekold colony of B. cinerea on potato on PDA d black sclerotia developed on PDA e conidia (White et al 1990), G3PDH-F (5′-ATTGACATCGTCGC TGTCAACGA-3′)/G3PDH-R (5′-ACCCCACTCGTTGT CGTACCA-3′), HSP60-F (5′-CAACAATTGAGATT TGCCCACAAG-3′)/HSP60-R (5′-GATGGATCCAGTGG TACCGAGCAT-3′) and RPB2-F (5′-GATGATCGTGATCA TTTCGG-3′)/RPB2-R (5′-CCCATAGCTTGCTTACCCAT-3′) (Staats et al 2005), respectively. The polymerase chain reaction (PCR) was performed in a 25 μL reaction mixture containing 0.5 μL of each primer (10 pmol/L), 0.5 μL of Taq DNA polymerase (Bioneer, Korea), 0.5 μL of each dNTP (10 mM), 2.5 μL of 10× PCR reaction buffer, 18.5 μL of distilled water, and 2.0 μL of template DNA.…”

Occurrence of Gray Mold Caused by Botrytis cinerea on Rubus crataegifolius in Korea

“…2A, 2B). 배양 10일 후부터 회색 균사체가 뭉쳐지면서 작은 소립의 균핵을 형성하 [5]. ITS 영역의 증폭에는 ITS1F/ITS4 primer pair를 이용하였으며 [6], RPB2 유전 자는 RPB2for/RPB2rev, HSP60 유전자는 HSP60for/HSP60rev, G3PDH 유전자는 G3PDH for/G3PDHrev primer pair를 사용하여 증폭하였다 [4].…”