Botrytis four species are associated with chocolate spot disease of faba bean in Latvia

Abstract

Faba bean (Vicia faba L.) is gaining importance as a crop in northern Europe. In this region, the most important disease of faba bean is chocolate spot disease, attributed to the pathogen Botrytis fabae. However, other Botrytis species have been found to contribute to the disease. Hence, it was decided to isolate fungi from faba bean plants showing symptoms of chocolate spot disease in Latvia, identify the Botrytis species using the DNA sequences of three definitive genes, evaluate the morphological diversity of the isolates in vitro and, finally, to determine the pathogenicity of the isolates in a detached-leaf test. In addition to B. fabae, B. cinerea, B. pseudocinerea and B. fabiopsis were all identified. Phylogenetic analysis of the DNA sequences put all the obtained 44 isolates unequivocally into clusters with known examples of each species. Every species showed wide diversity in its in vitro colour, texture and growing pattern of mycelium, production of sclerotia and pigmentation of the growing medium with much overlap between species showing that this method is not adequate for species discrimination. B. fabae produced the largest lesions on infected leaves, followed closely by B. pseudocinerea and B. cinerea, while B. fabiopsis produced much smaller lesions. The results show that chocolate spot disease of faba bean is attributable to Botrytis four species in northern Europe. This knowledge needs to be considered when controlling the disease by genetic or agronomic means.

Evaluation of pathogenicity of Botrytis species isolated from different legumes

“…These species have been much less studied than the previous two and found in relatively few countries. Both have been implicated in the chocolate spot disease of faba bean in several countries, including Latvia ( Bankina et al., 2021 ). B. pseudocinerea has been found in various unrelated host plants ( Plesken et al., 2015 ; Garfinkel, 2021 ).…”

“…The current study is the first report of B. fabiopsis naturally occurring in chickpea and the first demonstration that it can cause disease in pea, narrow-leafed lupin, yellow lupin and soybean. To date, no information is available on the occurrence of B. fabiopsis elsewhere than in faba bean in China ( Zhang et al., 2010 ) and Latvia ( Bankina et al., 2021 ).…”

“…B. pseudocinerea was first discovered in French vineyards, then isolated from faba bean in Germany, and increasing numbers of studies have revealed its presence on different host-plants in Europe, North America, China and Australia ( Walker et al., 2011 ; Saito et al., 2014 ; Harper et al., 2019 ; Xue et al., 2019 ; Plesken et al., 2021 ). These four Botrytis species have all been associated with the chocolate spot disease of faba bean, most recently in Latvia ( Bankina et al., 2021 ).…”

Detection, characterization, and management of plant pathogens

“…B. pseudocinerea was first discovered in French vineyards, then isolated from faba bean in Germany, and increasing numbers of studies have revealed its presence on different host-plants in Europe, North America, China and Australia (Walker et al, 2011;Saito et al, 2014;Harper et al, 2019;Plesken et al, 2021). These four Botrytis species have all been associated with the chocolate spot disease of faba bean, most recently in Latvia (Bankina et al, 2021).…”

First Report of Exserohilum Rostratum as a Potential Pathogen of the Faba Bean Leaf Spot Disease in Iraq

“…Faba bean plants sustain infections at different growth stages, with varied pathogens like bacteria, fungi, viruses, and numerous others, leading to significant production losses (Plūduma-Pauniņa et al, 2019). The diseases that infect vegetative parts are often severe in faba bean, such as chocolate spot (Botrytis fabae), Ascochyta blight (Didymella fabae), rust (Uromyces viciae-fabae), Cercospora leaf spot (Cercospora zonata), Stemphylium leaf blight (S. botryosum, S. eturmiunum, and S. vesicarium) (Stoddard et al, 2010;Bankina et al, 2017;Vaghefi et al, 2020). However, a report stated the Exserohilum rostratum species is a potential threat to numerous valuable plant species which belonging to 28 genera within 11 families (Vaghefi et al, 2020).…”