Botrytis cinerea is a major plant pathogen, causing gray mold rot in a variety of cultures. Repeated fungicide applications are common but have resulted in the development of fungal populations with resistance to one or more fungicides. In this study, we have monitored fungicide resistance frequencies and the occurrence of multiple resistance in Botrytis isolates from raspberries, strawberries, grapes, stone fruits and ornamental flowers in Germany in 2010 to 2015. High frequencies of resistance to all classes of botryticides was common in all cultures, and isolates with multiple fungicide resistance represented a major part of the populations. A monitoring in a raspberry field over six seasons revealed a continuous increase in resistance frequencies and the emergence of multiresistant Botrytis strains. In a cherry orchard and a vineyard, evidence of the immigration of multiresistant strains from the outside was obtained. Inoculation experiments with fungicide-treated leaves in the laboratory and with strawberry plants cultivated in the greenhouse or outdoors revealed a nearly complete loss of fungicide efficacy against multiresistant strains. B. cinerea field strains carrying multiple resistance mutations against all classes of site-specific fungicides were found to show similar fitness as sensitive field strains under laboratory conditions, based on their vegetative growth, reproduction, stress resistance, virulence and competitiveness in mixed infection experiments. Our data indicate an alarming increase in the occurrence of multiresistance in B. cinerea populations from different cultures, which presents a major threat to the chemical control of gray mold.

cBotrytis cinerea is one of the most important pathogens worldwide, causing gray mold on a large variety of crops. Botrytis pseudocinerea has been found previously to occur together with B. cinerea in low abundance in vineyards and strawberry fields. Here, we report B. pseudocinerea to be common and sometimes dominant over B. cinerea on several fruit and vegetable crops in Germany. On apples with calyx end rot and on oilseed rape, it was the major gray mold species. Abundance of B. pseudocinerea was often negatively correlated with fungicide treatments. On cultivated strawberries, it was frequently found in spring but was largely displaced by B. cinerea following fungicide applications. Whereas B. cinerea strains with multiple-fungicide resistance were common in these fields, B. pseudocinerea almost never developed resistance to any fungicide even though resistance mutations occurred at similar frequencies in both species under laboratory conditions. The absence of resistance to quinone outside inhibitors in B. pseudocinerea was correlated with an intron in cytB preventing the major G143A resistance mutation. Our work indicates that B. pseudocinerea has a wide host range similar to that of B. cinerea and that it can become an important gray mold pathogen on cultivated plants. Botrytis cinerea Pers.:Fr. is one of the most important plant pathogens worldwide, causing gray mold rot on far more than 200 plant species, including cultivated fruits, vegetables, and ornamental flowers. In addition to its wide host range, typical features of B. cinerea are a necrotrophic, macerating mode of infection, abundant production of asexual macroconidia on the surface of colonized host tissue, and formation of melanized sclerotia for long-term survival and sexual reproduction. Control of gray mold often relies on the use of fungicides although the efficacy of such treatments is threatened worldwide by the abundance of fungicide-resistant B. cinerea field strains (1). Based on gene sequence comparisons, the genus Botrytis has been divided into two phylogenetically separate clades (2). Clade 1 includes B. cinerea and B. pseudocinerea as well as the host-specific species B. fabae, B. calthae, and B. sinoviticola; all of these infect only dicot plants. Clade 2 is phylogenetically more diverse and currently comprises 23 host-specific Botrytis species that infect predominantly monocots (2-4).B. cinerea shows considerable variability in mycelial growth phenotype, conidiation, and sclerotium formation. Numerous studies have also documented a high degree of genetic variability within the species. Based on the analysis of PCR-restricted fragment length polymorphism (RFLP) patterns, fungicide resistance, and the detection of transposable elements, Giraud et al. provided evidence of the existence of genetically distinct groups within B. cinerea (5, 6). In particular, the presence or absence of the long terminal repeat retrotransposon Boty (7) and of the DNA transposon Flipper (8) was used to divide isolates into different transposon types, e...

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causes pre- and postharvest decay of many fruit and vegetable crops. A survey of German strawberry fields revealed strains that differed from in diagnostic PCR markers and growth appearance. Phylogenetic analyses showed that these strains belong to an undescribed species in clade 2, named sp. nov. Isolates of were detected in strawberry fields throughout Germany, sometimes at frequencies similar to those of, and in the southeastern United States. was isolated from overwintering strawberry tissue but not from freshly infected fruit. invaded strawberry tissues with an efficiency similar to or lower than that of but showed poor colonization of inoculated nonhost plant tissues. These data and the exclusive occurrence of this fungus on strawberry plants indicate that is host specific and has a tissue preference different from that of Various fungicide resistance patterns were observed in populations. Many strains showed resistance to one or several chemical classes of fungicides and an efflux-based multidrug resistance (MDR1) phenotype previously described in Resistance-related mutations in were identical or similar to those of for carbendazim (E198A mutation in ), azoxystrobin (G143A in), iprodione (G367A+V368F in ), and MDR1 (gain-of-function mutations in the transcription factor gene and overexpression of the drug efflux transporter gene ). The widespread occurrence of indicates that this species is adapted to fungicide-treated strawberry fields and may be of local importance as a gray mold pathogen alongside Gray mold is the most important fruit rot on strawberries worldwide and requires fungicide treatments for control. For a long time, it was believed to be caused only by, a ubiquitous pathogen with a broad host range that quickly develops fungicide resistance. We report the discovery and description of a new species, named , that is widely distributed in commercial strawberry fields in Germany and the southeastern United States. It was observed on overwintering tissue but not on freshly infected fruit and seems host specific on the basis of its occurrence and artificial infection tests. has also developed resistance to several fungicides that is caused by mutations similar to those known in , including an efflux-based multidrug resistance. Our data indicate that could be of practical importance as a strawberry pathogen in some regions where its abundance is similar to that of .

Pulsatile positive displacement pumps as ventricular assist devices were gradually replaced by rotary devices due to their large volume and high adverse event rates. Nevertheless, pulsatile ventricular assist devices might be beneficial with regard to gastrointestinal bleeding and cardiac recovery. Therefore, aim of this study was to investigate the flow field in new pulsatile ventricular assist devices concepts with an increased pump frequency, which would allow lower stroke volumes to reduce the pump size. We developed a novel elliptically shaped pulsatile ventricular assist devices, which we compared to a design based on a circular shape. The pump size was adjusted to deliver similar flow rates at pump frequencies of 80, 160, and 240 bpm. Through a computational fluid dynamics study, we investigated flow patterns, residence times, and wall shear stresses for different frequencies and pump sizes. A pump size reduction by almost 50% is possible when using a threefold pump frequency. We show that flow patterns inside the circular pump are frequency dependent, while they remain similar for the elliptic pump. With slightly increased wall shear stresses for higher frequencies, maximum wall shear stresses on the pump housing are higher for the circular design (42.2 Pa vs 18.4 Pa). The calculated blood residence times within the pump decrease significantly with increasing pump rates. A smaller pump size leads to a slight increase of wall shear stresses and a significant improvement of residence times. Hence, high-frequency operation of pulsatile ventricular assist devices, especially in combination with an elliptical shape, might be a feasible mean to reduce the size, without any expectable disadvantages in terms of hemocompatibility.