In September 2019, two diseased plants of Campsis grandiflora showing the main symptom of witches' ‐broom (CgWB) were found in a nursery garden in Yangling, Shaanxi province, China. Partial 16S ribosomal RNA (F2nR2 region) and ribosomal protein (rp) genes of phytoplasmas were generated from the symptomatic plants by PCR amplification, and phytoplasma bodies were observed in the sieve tube elements of the CgWB samples under a transmission electron microscope, indicating phytoplasma infection in the two CgWB plants. Restriction fragment length polymorphism analysis of the F2nR2 region and similarity coefficient results suggested that the two associated phytoplasmas belong to two novel subgroups of 16SrI (aster yellows) group, designated as AK and AL. On the reconstructed phylogenetic trees based on F2nR2 regions and rp genes of phytoplasmas, respectively, the CgWB‐associated phytoplasmas clustered together with members of 16SrI subgroups. This was the first record of phytoplasmas infecting C. grandiflora worldwide.

Alternaria foliar diseases are important factors that pose a significant threat to yield in solanaceous crops. To clarify the diversity of large‐spored Alternaria species in China, diseased leaves of three solanaceous vegetables (potato, tomato and eggplant) were collected and used for fungal isolation. In total, 67 strains representing six species in section Porri of Alternaria were isolated, based on morphological characterizations and multilocus phylogenetic analyses. There were three known species (A. blumeae, A. linariae and A. solani), one new record of A. argyroxiphii and two new species, A. melongenicola sp. nov. and A. yichangensis sp. nov. The sequence analyses encompassed the internal transcribed spacer region of rDNA (ITS), glyceraldehyde‐3‐phosphate dehydrogenase (GAPDH), Alternaria major allergen (Alt a 1), translation elongation factor 1‐α (TEF1) and RNA polymerase second largest subunit (RPB2). To confirm pathogenicity, 15 representative strains were evaluated for their virulence under greenhouse conditions. The results revealed that they were able to induce leaf spot symptoms on potato, tomato and eggplant plants with a range of aggressive abilities. The present study provides a basis for the recognition and management of Alternaria foliar diseases.