First detection of viral pathogens of chickpea in Germany

Legumes play a crucial role in agriculture and serve as a valuable source of protein for human and animal consumption. However, legumes are susceptible to various viral infections, which can cause significant losses in yield and quality. Chickpea (Cicer arietinum L.) is an important food legume worldwide. While its cultivation in Germany is still in its infancy, it is expected to increase due to its numerous advantages. It is adapted to drought conditions, is an attractive additional option for crop rotations in organic farming and is gaining popularity for regionally produced food products. However, there is little knowledge about the presence and potential agronomic impact of viral pathogens in chickpea grown under German conditions. This study is the first that investigated the prevalence of legume-infecting viruses on chickpea crops grown in Germany. In 2022 and 2023, we collected sample material from symptomatic plants at three locations and analyzed it for the presence of circular (ss) DNA viruses, such as pea necrotic yellow dwarf virus (PNYDV), using a combination of rolling circle amplification (RCA) and downstream restriction fragment length pattern (RFLP) analysis. Furthermore, we conducted a reverse transcription PCR assay to detect different legume-infecting RNA viruses. In 2022 PNYDV was detected in 5 plants, all from the ‘Amorgos’ chickpea variety, located near a pea field. RNA viruses were detected in 27 plants, mostly TuYV or PEMV-1. Double and triple infections were common, with one plant exhibiting a triple infection of PNYDV, TuYV and PEMV-1. Symptoms of viral infection included leaf yellowing, dwarfism and chlorotic spots, with coinfections leading to more severe symptoms. In 2023, pea, cowpea and chickpea samples were collected from Schleibnitz/Wanzleben, Saxony- Anhalt, along with various chickpea accessions and cultivars from ZALF experimental fields, where the presence of PSbMV, PEMV, PNYDV, BYMV and TuYV was confirmed across these hosts. These findings indicate that viral pathogens pose a significant threat to chickpea production in Germany, necessitating the development of resistant cultivars and integrated management strategies.