Different Infectivity of Mediterranean and Southern Asian Tomato Leaf Curl New Delhi Virus Isolates in Cucurbit Crops

Abstract

Tomato leaf curl New Delhi virus (ToLCNDV) became an alerting virus in Europe from 2017 to 2020 because of its significant damage to Cucurbitaceae cultivation. Until now, just some cucurbit crops including sponge gourd, melon, pumpkin, and cucumber were reported to be resistant to ToLCNDV, but no commercial cultivars are available. In this study, a new isolate of ToLCNDV was identified in Pakistan and analyzed together with ToLCNDV-ES which was previously isolated in Italy. Furthermore, infectious clones of two ToLCNDV isolates were constructed and agroinoculated into different cucurbit crops to verify their infectivity. Results showed that both isolates exhibited severe infection on all tested cucurbit (>70%) except watermelon. Thus, those cultivars may be good candidates in the first step of screening genetic resources for resistance on both Southeast Asian and Mediterranean ToLCNDV isolates. Additional, comparison pathogenicity of different geographical ToLCNDV isolates will be aided to understand viral characterization as such knowledge could facilitate breeding resistance to this virus.

ToLCNDV-ES infection in tomato is enhanced by TYLCV: Evidence from field survey and agroinoculation

“…Overall, data obtained from field and agroinoculation tests suggested also a possible different infectivity in tomato between subgroup I and subgroup II of Italian ToLCNDV isolates, with subgroup I unable to infect tomato even at subliminal mode. Similar results were also obtained in a previous study, concerning the different infectivity in cucurbits between the same ToLCNDV-ES Italian isolate and a ToLCNDV Pakistani isolate ( Vo et al, 2022 ). Interestingly, the Italian subgroup I is phylogenetically more distantly related to the ToLCNDV Asian strain than the Italian subgroup II of ToLCNDV isolates ( Panno et al, 2019 ).…”

“…The recombinant pCAM-TYLCV-1.1 mer was the used to transform the Agrobacterium tumefaciens strain GV3101 by electroporation. By using the same approach described, a ToLCNDV-ES infectious clone was successfully constructed in a previous study by using a ToLCNDV-ES Italian isolate from pumpkin ( Parrella et al, 2018 ; Vo et al, 2022 ).…”

“…In a previous study, an infectious clone of ToLCNDV-ES that was obtained from a ToLCNDV-infected pumpkin plant, identified in Campania region (Southern continental Italy), was successfully constructed and its biological features were compared with that of an Asian strain, especially in cucurbits ( Parrella et al, 2018 ; Vo et al, 2022 ).…”

Insights into the Differential Composition of Stem-Loop Structures of Nanoviruses and Their Impacts

“…All original MDV segments were already constructed and available in the authors’ laboratory. To make an IC of mutant virus, the same method of IC construction with slight modifications was used as in the case of geminiviruses ( 43 , 44 ). Two partial genomes of each virus sequence containing restriction sites at the edges were amplified to make infectious clones using primer sets based on the extracted sequence as shown in schematic diagram of MDV DNA R (Fig.…”

Construction of an Agroinfectious Clone of a Korean Isolate of Sweet Potato Symptomless Virus 1 and Comparison of Its Infectivity According to Agrobacterium tumefaciens Strains in Nicotiana benthamiana

“…SPSMV-1 isolate. An infectious clone of the Korean SPS-MV-1 isolate was obtained by constructing a partial tandem repeat of the full-length viral DNA as previously described (Urbino et al, 2008;Vo et al, 2022) (Fig. 1).…”