Search

Botrytis cinerea is considered to be the second most destructive fungal pathogen worldwide, causing severe pre‐ and postharvest losses in cut roses. However, to date, no systematic research on its characteristics in cut roses has been reported. In our study, a total of 100 isolates from cut roses from Yunnan, China, were analysed. A combination of morphological characteristics and phylogenetic analysis of RPB2 revealed that 100 isolates were of the species B. cinerea. These isolates were pathogenic on unwounded detached rose petals. Pathogenicity was evaluated according to the size of petal spots and categorized into grades 0–5, from weak to strong. The inhibition rate varied greatly following the addition of procymidone (21.9%–100%) and cyprodinil (25.0%–92.3%). Analysis of Bc‐hch sequences revealed all isolates belong to phylogenetic Group II. According to the presence or absence of transposable elements, 87, 5, 4 and 4 isolates were identified as transposa, vacuma, Boty‐only and Flipper‐only types, respectively. Detection of mating type indicated that all isolates were heterothallic with 45% belonging to MAT1‐1 and 55% to MAT1‐2. Isolates were divided into four subpopulations when analysing single‐nucleotide polymorphisms at the genomic level, with a significant difference in pathogenicity between subpopulations 1 and 4. The evolutionary tree indicated that isolates AN‐02, AN‐22 and SM‐C18 were clustered in the root, suggesting an earlier evolutionary time than other isolates; moreover, they all exhibited low pathogenicity (grade 1). This systematic study of the characteristics of B. cinerea will provide significant support for grey mould control and further research. [ABSTRACT FROM AUTHOR]

The horticulturally important genus Zantedeschia (Araceae) comprises eight species of herbaceous perennials. We sequenced, assembled and analyzed the chloroplast (cp) genomes of four species of Zantedeschia ( Z. aethiopica , Z. odorata , Z. elliottiana , and Z. rehmannii ) to investigate the structure of the cp genome in the genus. According to our results, the cp genome of Zantedeschia ranges in size from 169,065 bp ( Z. aethiopica ) to 175,906 bp ( Z. elliottiana ). We identified a total of 112 unique genes, including 78 protein-coding genes, 30 transfer RNA (tRNA) genes and four ribosomal RNA (rRNA) genes. Comparison of our results with cp genomes from other species in the Araceae suggests that the relatively large sizes of the Zantedeschia cp genomes may result from inverted repeats (IR) region expansion. The sampled Zantedeschia species formed a monophylogenetic clade in our phylogenetic analysis. Furthermore, the long single copy (LSC) and short single copy (SSC) regions in Zantedeschia are more divergent than the IR regions in the same genus, and non-coding regions showed generally higher divergence than coding regions. We identified a total of 410 cpSSR sites from the four Zantedeschia species studied. Genetic diversity analyses based on four polymorphic SSR markers from 134 cultivars of Zantedeschia suggested that high genetic diversity ( I  = 0.934; Ne  = 2.371) is present in the Zantedeschia cultivars. High genetic polymorphism from the cpSSR region suggests that cpSSR could be an effective tool for genetic diversity assessment and identification of Zantedeschia varieties., Competing Interests: The authors declare there are no competing interests., (©2020 He et al.)