The genus Passiflora, commonly known as passion fruit, originated in South America, is an economically important horticulture crop and widely distributed in the tropics and subtropics. Yellow passion fruit (Passiflora edulis f. flavicarpa) and purple passion fruit (Passiflora edulis f. edulis) are the two most planted species (Santos-Jiménez et al., 2022), which have been largely cultivated in southern China. The average annual production reaches 600,000 tons, of which yellow fruit accounts for more than 70% (Zhou et al., 2022). In 2022 to 2023, a disease caused flower rot severely in passion fruit plantations. The incidence rate was generally 10% in purple passion fruit, with an incidence up to 60% in yellow passion fruit 'Qinmi No. 9'. Flower rot occurs mainly in the rainy season, especially during periods of prolonged rain. Infected flowers had black patches that were water-soaked on the interior of the flower bud. The patches covered the entire flower bud, and fluffy mycelium and sporangia developed, which caused the flower bud rotten and abscised easily. Five symptomatic flowers from Wuhua, Guangdong (23°23'N, 115°18'E) and 8 symptomatic flowers from Shangsi, Guangxi (21°15'N, 107°98'E) of 'Qinmi No. 9' were collected during flowering period in 2022 and 2023. Diseased flower pieces were surface-sterilized with 70% ethanol for 2 to 3 min, rinsed with sterile distilled water 3 times, and placed on PDA medium at 25℃ in darkness. Four and 6 fungal isolates with similar morphology were isolated from the infected samples of Wuhua and Shangsi, respectively. Two isolates, PRFJ01 from Wuhua and PRGX02 from Shangsi, were randomly selected for further study. Purified fungal colonies at the age of 3 days accompany with diffuse cottony mycelia, turned white to gray later. The mycelia were hyaline and aseptate. Sporangiophores with 0.56 (0.22~1.10) mm in length and 6.1 (3.18~10.87) μm in width (n=100) were erect, light brown, and had rhizoids and stolons at their bases. Sporangia with 48.0 (23.45~92.85) μm in diameter (n=100) were dark-colored, near spherical and having dark ovoid sporangiospores with 3.56 (2.34~6.39) μm × 2.82 (1.73~4.70) μm (n=100). The morphology of the fungus were identical to Rhizopus stolonifer (Ehrenb.) Vuill (Haque et al. 2023). The two isolates were molecularly identified using genomic regions of 28S large ribosomal subunit (LSU) with NL1 and LR3 primers (Cruz-Lachica et al., 2018). The phylogenetic trees revealed the sequences of PRFJ01 (OR801560.1) and PRGX02 (OR801561.1) were 100% and 99% identical to R. stolonifer (MK705761.1 and KC412868.1), respectively. Pathogenicity tests were conducted on healthy flowers and leaves of 5-month-old grafted 'Qinmi No. 9' plants. Mycelial plugs with 5-mm diameter were placed on the flowers and leaves. Three plants were performed for each of the isolates, and the test was repeated twice. The inoculated plants were moisturized with plastic bags. Healthy flowers and leaves inoculated with sterile PDA plugs were used as control. Typical symptoms were observed on inoculated plants after 2 days. The dark grey mycelia and sporangia covered the entire flower after 4 days inoculation. The flower bud became putrid and the flower stalk split off. Lesions on leaves expanded accompany with numerous aerial mycelium. However, the controls were symptomless. R. stolonifer was reisolated from inoculated tissues. Previously, flower rot on passion fruit caused by R. stolonifer has only been recorded in Brazil (Ploetz, 2003). To our knowledge, this is the first report of R. stolonifer causing flower rot on passion fruit in China.

Fusarium oxysporum f. sp. cubense (Foc) causes Fusarium wilt, a devastating epidemic disease that has caused widespread damage to banana crops worldwide. We report the draft genomes of Foc race 1 (16117) and Foc tropical race 4 (Fusarium odoratissimum) (CNSD1) isolates from China, assembled using PacBio HiFi sequencing reads, with functional annotation performed. The strains group in distinct lineages within the Fusarium oxysporum species complex. This genetic resource will contribute towards understanding the pathogenicity and evolutionary dynamics of Foc populations in banana-growing regions around the world.

Anubias (Araceae) is a globally important group of ornamental aquatic plants. However, when temperatures drop to 10 °C, most species suffer obvious frostbite from cold stress, restricting winter cultivation and broader application. This study focused on two Anubias genotypes with distinct cold tolerance, adopting an integrated approach combining phenotypic, physiological, metabolomic, and transcriptomic analyses to reveal the mechanisms underlying their differential cold tolerance. Under 10 °C cold stress, compared with normal temperatures, the leaves of cold-tolerant Anubias sp. ‘Long Leaf’ (Jian) showed no significant frostbite, while cold-sensitive Anubias barteri var. nana ‘Coin Leaf’ (Jin) had clear frost damage. Both genotypes exhibited increased leaf relative electrical conductivity, malondialdehyde (MDA) content, soluble sugar content, and activities of superoxide dismutase (SOD) and catalase (CAT); “Jian” had more notable rises in SOD/CAT activities and maintained higher levels, whereas “Jin” showed greater increases in conductivity, MDA, and soluble sugar. Metabolomic and transcriptomic analyses revealed “Jian” specifically upregulated metabolites in pathways like flavone and flavonol biosynthesis and tryptophan metabolism, as well as genes related to valine, leucine, isoleucine degradation and phenylpropanoid biosynthesis pathways. ERFs, WRKYs, NACs and other transcription factors correlated with these differentially expressed genes, suggesting potential transcriptional regulation. These results provides insights for breeding cold-tolerant Anubias and optimizing low-temperature cultivation.

Fusarium oxysporum f. sp. cubense (Foc) causes Fusarium wilt, a devastating epidemic disease that has caused widespread damage to banana crops worldwide. We report the draft genomes of Foc race 1 (16117) and Foc tropical race 4 (Fusarium odoratissimum) (CNSD1) isolates from China, assembled using PacBio HiFi sequencing reads, with functional annotation performed. The strains group in distinct lineages within the Fusarium oxysporum species complex. This genetic resource will contribute towards understanding the pathogenicity and evolutionary dynamics of Foc populations in banana-growing regions around the world.