1Alma Mater Studiorum - University of Bologna, Department of Agricultural and Food Sciences, Bologna, Italy
2Department of Botany, DDU Gorakhur University, Gorakhpur, Uttar Pradesh, India
3Discipline of Life Sciences, Indira Gandhi National Open University, New Delhi, India
4Division of Plant Pathology, Indian Agricultural Research Institute, New Delhi, India
*Corresponding author e-mail: Francesco Pacini (francesco.pacini2@unibo.it)
Online published on 10 February, 2021.
Five samples were collected from neem trees exhibiting little leaf and witches’ broom in Gorakhpur, Uttar Pradesh, India during August 2019 surveys. Molecular analyses were conducted for detection, identification and characterization of phytoplasmas associated with this disease. The identity of phytoplasmas detected in neem samples was confirmed through PCR/RFLP analyses using phytoplasma 16Sr RNA gene universal primers and primers amplifying portions of the secA and leu genes. In all the positive samples, the presence of a’ Candidatus Phytoplasma trifolii’-related strain was identified. The phytoplasma identification was confirmed by 100% identity with Ca. P trifolii’ strains. The RFLP analyses on 16S ribosomal gene allowed to determine that this phytoplasma could be enclosed in 16SrVI-D subgroup. RFLP and sequencing analyses on secA gene showed also the presence of a strain related to Ca. P asteris’, indicating the presence of mixed infection with two phytoplasmas. This is the first report of 16SrVI and 16SrI mixed phytoplasma infection in severely symptomatic neem trees.
Phytoplasma disease, 16S rRNA gene, Seca gene, Leu gene, Molecular detection
