Phenotypic Variation of Botrytis cinerea Isolates Is Influenced by Spectral Light Quality

Abstract

Botrytis cinerea, a fungal pathogen that causes gray mold, displays a high degree of phenotypic diversity. Light emitting diodes (LEDs) with specific light spectrum are increasingly used as lighting resource for plant greenhouse production. The chosen light spectrum can also have an effect on the pathogens in this production system. In this study, we investigated the phenological diversity in 15 B. cinerea isolates upon different light treatments. Daylight, darkness, and LED lights with different wavelengths (white, blue, red, blue+red) were chosen as treatments. The 15 Botrytis isolates differed in their mycelial growth rate, conidia production, and sclerotia formation. Light quality had a limited effect on growth rate. All isolates sporulated under daylight treatment, red light resulted in lower sporulation, while white, blue, and blue+red light inhibited sclerotia formation in all isolates, and sporulation in most, but not all isolates. Pathogenicity of the Botrytis isolates was studied on 2-week-old strawberry (Fragaria × ananassa 'Elsanta') leaves grown under white, blue, and red LED lights. The isolates differed in virulence on strawberry leaves, and this was positively correlated to oxalic acid production by B. cinerea in vitro. Red LED light improved leaf basal resistance to all the tested Botrytis isolates. Blue light pretreatment resulted in decreased leaf resistance to some isolates. Furthermore, we used image analysis to quantify the virulence of the different Botrytis isolates based on changes in photosynthetic performance of the strawberry leaves: chlorophyll fluorescence (F v /F m), chlorophyll index (ChlIdx) and anthocyanin content (modified anthocyanin reflection index, mAriIdx). F v /F m showed a strong negative correlation with disease severity and can be an indicator for the early detection of gray mold on strawberry leaves.

The phenylpropanoid pathway inhibitor piperonylic acid induces broad-spectrum pest and disease resistance in plants

“…Bioassays with Botrytis cinerea R16 (Faretra & Pollastro 1991) were performed as in Audenaert et al (2002) using tomato leaves from four-week old plants detached 24 h after the second PA treatment. Four dai, disease progression was monitored in a phenotyping robot as in Meng et al (2020). N = 8 (8 plants, 32 leaflets), repeated twice.…”

Population Genetic Analyses of Botrytis cinerea Isolates From Michigan Vineyards Using a High-Throughput Marker System Approach

“…Genetic polymorphisms in transposable element presence and a group of genes including Bc-hch, erg27, sdh, and cyp51 between B. cinerea and B. pseudocinerea provided evidence for the differentiation of B. pseudocinerea as a new species (Fournier et al, 2003;Walker et al, 2011;Plesken et al, 2015). Within B. cinerea sensu stricto, a large variability in genetic and phenotypic diversity, and host specialization have also been observed (Corwin et al, 2016;Mercier et al, 2019;Soltis et al, 2019;Meng et al, 2020).…”

Hormetic Responses of Photosystem II in Tomato to Botrytis cinerea

“…The development of the method of chlorophyll fluorescence imaging analysis (CF-IA) permits the revealing of the leaf spatiotemporal photosynthetic heterogeneity at the total leaf surface, that is ignored when measuring chlorophyll fluorescence with the classical point measurement techniques [ 18 , 20 , 21 , 22 , 23 ]. CF-IA is a highly effective non-invasive method for the estimation of the inhibition or damage in the PSII electron transfer process, serving as an extremely sensitive indicator of photosynthetic efficiency under both biotic and abiotic stress conditions [ 24 , 34 , 35 , 36 , 37 , 38 , 39 ]. The fact that biotic stresses are typically heterogeneous, being spatiotemporal, renders chlorophyll fluorescence imaging apparatuses powerful tools to study the impact of biotic stress on leaf photosynthetic performance [ 37 ].…”