High-Quality Genome Assembly and Annotation Resource of Elsinoë annonae, Causing Fruit Scab on Camellia oleifera.

Elsinoë annonae is a fungal pathogen that causes fruit scab disease in the edible-oil (tea oil) plant (Camellia oleifera Abel). The absence of genome resources for this fungus hampers functional genetic studies of the pathogenesis mechanism of E. annonae. This study reports the genome assembly of E. annonae strain SM-YC-2 collected from tea oil tree fruit with scab disease in Fujian Province, China. Combining 16.44 Gb of PacBio Sequel II long reads and 5.13 Gb of Illumina NovaSeq reads, we generated a 25.93-Mb (99.19% of expected genome size) high-quality genome assembly with 52.66% GC content, 5.05% repeats, and over 98% Benchmarking Universal Single-Copy Orthologs completeness for E. annonae strain SM-YC-2. These high-quality genome assembly resources will facilitate functional genomic characterization studies, enhance insights into the pathogenicity mechanism of E. annonae, and support the development of molecular-based control strategies.

Identification and Biological Characteristics of Mortierella alpina Associated with Chinese Flowering Cherry (Cerasus serrulata) Leaf Blight in China.

The Chinese flowering cherry (Cerasus serrulata), an ornamental tree with established medicinal values, is observed to suffer from leaf blight within Xi'an's greenbelts. This disease threatens both the plant's growth and its ornamental appeal. In this study, 26 isolates were obtained from plants with typical leaf blight, and only 3 isolates (XA-10, XA-15, and XA-18) were found to be pathogenic, causing similar symptoms on the leaves of the host plant. Based on sequence alignment, the ITS and LSU sequences of the three selected isolates were consistent, respectively. Following morphological and molecular analyses, the three selected isolates were further identified as Mortierella alpina. The three selected isolates exhibited similar morphological characteristics, including wavy colonies with dense, milky-white aerial mycelia on PDA medium. Therefore, isolate XA-10 was used as a representative strain for subsequent experiments. The representative strain XA-10 was found to exhibit optimal growth at a temperature of 30 °C and a pH of 7.0. Host range infection tests further revealed that the representative strain XA-10 could also inflict comparable disease symptoms on both the leaves and fruits of three different Rosaceae species (Prunus persica, Pyrus bretschneideri, and Prunus salicina). This study reveals, for the first time, the causative agent of leaf blight disease affecting the Chinese flowering cherry. This provides a deeper understanding of the biology and etiology of M. alpina. This study lays a solid foundation for the sustainable control and management of leaf blight disease in the Chinese flowering cherry.