Phytophthora Diversity in a Sentinel Arboretum and in a Nature Reserve Area

Most soilborne Phytophthora species are invasive plant pathogens and nursery plants for transplanting are considered a primary pathway for the introduction of exotic Phytophthora species into plant diversity conservation areas and sites. As a preliminary step toward investigating this subject, we compared the diversity of Phytophthora in the protected natural area Complesso Speleologico Villasmundo S. Alfio Nature Reserve (NR) (Melilli, Siracusa) and the botanical garden (BG) of the University of Catania (Catania), in eastern Sicily (southern Italy). Sampling was carried out during the spring of 2019. Overall 29 rhizosphere soil samples were collected, 17 from different types of vegetation …

Bot gummosis of lemon (Citrus × limon) caused by neofusicoccum parvum

Neofusicoccum parvum, in the family Botryosphaeriaceae, was identified as the causal agent of bot gummosis of lemon (Citrus × limon) trees, in the two major lemon-producing regions in Italy. Gummy cankers on trunk and scaffold branches of mature trees were the most typical disease symptoms. Neofusicoccum parvum was the sole fungus constantly and consistently isolated from the canker bark of symptomatic lemon trees. It was identified on the basis of morphological characters and the phylogenetic analysis of three loci, i.e., the internal transcribed spacer of nuclear ribosomal DNA (ITS) as well as the translation elongation factor 1-alpha (TEF1) and β-tubulin (TUB2) genes. The pathogenicity o…

Phytophthora Root and Collar Rot of Paulownia, a New Disease for Europe

Paulownia species are fast growing trees native to China, which are being grown in managed plantings in several European countries for the production of wood and biomasses. In 2018, wilting, stunting, leaf yellowing, and collapse, as a consequence of root and crown rot, were observed in around 40% of trees of a 2-year-old planting of Paulownia elongata × P. fortunei in Calabria (Southern Italy). Two species of Phytophthora were consistently recovered from roots, basal stem bark, and rhizosphere soil of symptomatic trees and were identified as Ph. nicotianae and Ph. palmivora on the basis of both morphological characteristics and phylogenetic analysis of rDNA ITS sequences. Koch’s postulates…

First report of postharvest fruit rot caused by fusarium sacchari on lady finger banana in Italy

Twig and Shoot Dieback of Citrus, a New Disease Caused by Colletotrichum Species

(1) Background: This study was aimed at identifying the Colletotrichum species associated with twig and shoot dieback of citrus, a new syndrome occurring in the Mediterranean region and also reported as emerging in California. (2) Methods: Overall, 119 Colletotrichum isolates were characterized. They were recovered from symptomatic trees of sweet orange, mandarin and mandarin-like fruits during a survey of citrus groves in Albania and Sicily (southern Italy). (3) Results: The isolates were grouped into two distinct morphotypes. The grouping of isolates was supported by phylogenetic sequence analysis of two genetic markers, the internal transcribed spacer regions of rDNA (ITS) and β-tubulin …