Molecular characterization of 'Candidatus Phytoplasma solani' in celery: Case study in Futog

Abstract

'Candidates Phytoplasma solani', known by its trivial name stolbur phytoplasma, is a plant pathogen infecting numerous crops in Serbia. Celery plants with prominent leaf yellowing and chlorosis, sporadically with tissue necrosis, were observed during August 2020 in Futog, situated in Novi Sad suburbia in Vojvodina. Total of 12 sampled celery plants, 8 symptomatic and 4 asymptomatic ones, were analysed for 'Ca. P. solani' presence. All symptomatic celery plants were infected with stolbur phytoplasma according to the stoll 1 gene detection and therefore were further subjected to multigene molecular characterization on three genes: tuf, stamp and vmpl. Combining molecular tools PCR/RFLP and sequencing reviled two 'Ca. P. solani' multilocus genotypes in celery: tuf-b/Rqg31/V14 and tuf-b/ Rpm35/V14, present in 4 samples each. Obtained results of the strain genotyping are in concordance with previous data on the 'Ca. P. solani' diversity on celery, but supplemented with genotyping of the vmpl gene. Outbreak of stolbur phytoplasma in the assessed locality in Futog is linked to tuf-b epidemiological cycle correlated in Serbia mainly with weed Convolvulus arvensis which was present in the subjected celery plot, and could have been the phytoplasma inoculum source. Visual evaluation of the symptom occurrence suggests on 10-15% of 'Ca. P. solani' affected celery plants scattered throughout the plot corresponding to the pathogen dispersal in crop by cixiid planthoper Hyalesthes obsoletus (Hemiptera: Auchenorrhyncha) associated with C. arvensis, main vector of stolbur phytoplasma in Serbia.

The Effect of Biotic Stress in Plant Species Induced by ‘Candidatus Phytoplasma solani’—An Artificial Neural Network Approach

“…phytoplasma solani' strains should be directed toward the sequencing and analysis of multiple housekeeping genes such as tuf, secY, vmp1, stamp, etc. [8,43], which could eventually reveal some genetic differences.…”

“…Diseases caused by phytoplasmas pose a threat to agricultural production by leading to substantial losses in yield and the quality of plants. More than 600 diverse diseases have been reported worldwide, mainly on vegetable crops belonging to the families Apiaceae, Asteraceae, Cucurbitaceae, Fabaceae, and Solanaceae [5][6][7][8]. The symptoms of diseases caused by phytoplasmas include yellowing or reddening of leaves, phyllody, stunting, virescence, shortened internodes, big bud, little leaf, witches' broom or proliferation, leaf curl, giant calyx, floral malformation, and vascular discoloration [7,9].…”