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The development of brown rot in stone fruit caused by the necrotrophic fungus Monilinia spp. is influenced by many abiotic factors, such as temperature, humidity, and light. Specifically, filamentous fungi perceive light as a signal for ecophysiological and adaptive responses. We have explored how specific light wavelengths affect the in vitro development, the regulation of putative development genes and the virulence of the main species of Monilinia (M. laxa, M. fructicola and M. fructigena). After subjecting Monilinia spp. to different light wavelengths (white, black, blue, red, far-red) for 7 days, several differences in their phenotype were observed among light conditions, but also among species. These species of Monilinia exhibited a different phenotypic plasticity in response to light regarding pigmentation, growth, and specially conidiation of colonies. In this sense, we observed that the conidial production was higher in M. laxa than M. fructicola, while M. fructigena showed an inability to produce conidia under the tested conditions. Growth rate among species was significantly lower in M. fructicola under red light wavelength while among light conditions it was increased under far-red light wavelength for M. laxa and under black light for M. fructicola; in contrast, no statistical differences were observed for M. fructigena. Gene expression analysis of 13 genes involved in fungal development of Monilinia spp. revealed a significant difference among the three species of Monilinia, and especially depended on light wavelengths. Among them, a high expression of OPT1, RGS2, RGS3 and SPP1 genes was observed in M. laxa, and LTF1 and STE12 in M. fructicola under black light. In contrast, a high expression of REG1 and C6TF1 genes occurred in both M. fructicola and M. laxa subject to red and far-red light wavelength, respectively. When nectarines were artificially infected with M. laxa and M. fructicola subjected to black light, the virulence was clearly reduced, but not in M. fructigena. Overall, results presented herein demonstrate that light wavelengths are a key abiotic factor for the biology of Monilinia spp., specially modulating its capacity to form conidia, and thus, influencing its spreading and the onset of the disease on nectarines during postharvest info:eu-repo/semantics/acceptedVersion

Supplemental material, sj-pdf-1-fst-10.1177_1082013220959988 for Scrutinising the relationship between major physiological and compositional changes during ‘Merrill O’Henry’ peach growth with brown rot susceptibility by Núria Baró-Montel, Jordi Giné-Bordonaba, Rosario Torres, Núria Vall-llaura, Neus Teixidó and Josep Usall in Food Science and Technology International

Resumen del trabajo presentado al Vth International Symposium on Postharvest Pathology, celebrado en Liège (Bélgica) del 19 al 24 de mayo de 2019., Authors are grateful to Spanish Government for their financial support by national projects AGL2014-55287-C02-02 and RTA2015-00050-00-00 from Ministry of Economy, Industry and Competitiveness (MINECO) and to the Catalan Government (Generalitat de Catalunya) for the PhD grant 2016FI_B_00442 (Baró-Montel, N.) and for the funding received from CERCA Programme / Generalitat de Catalunya. Thanks are also given to Severo Ochoa Program for Centres of Excellence in R&D 2016-2019 (SEV-2015-0533).

BACKGROUND: The biocontrol agent Candida sake CPA‐1 is effective against several diseases. Consequently, the optimisation of a dry formulation of C. sake to improve its shelf life and manipulability is essential for increasing its potential with respect to future commercial applications. The present study aimed to optimise the conditions for making a dry formulation of C. sake using a fluidised bed drying system and then to determine the shelf life of the optimised formulation and its efficacy against Penicillium expansum on apples. RESULTS: The optimal conditions for the drying process were found to be 40 °C for 45 min and the use of potato starch as the carrier significantly enhanced the viability. However, none of the protective compounds tested increased the viability of the dried cells. A temperature of 25 °C for 10 min in phosphate buffer was considered as the optimum condition to recover the dried formulations. The dried formulations should be stored at 4 °C and air‐packaged; moreover, shelf life assays indicated good results after 12 months of storage. The formulated products maintained their biocontrol efficacy. CONCLUSION: A fluidised bed drying system is a suitable process for dehydrating C. sake cells; moreover, the C. sake formulation is easy to pack, store and transport, and is a cost‐effective process. We are grateful to the INIA (Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria) and the FEDER (Fondo Europeo de Desarrollo Regional) for financial support via national project RTA2012‐00067‐C02‐01. In addition, we are also grateful to the INIA and FSE (Fondo Social Europeo) for the PhD grant to A. Carbó and CERCA Programme/Generalitat de Catalunya.

10 pág., The microbial variability on the host plant surface must be maintained because population diversity and quantity are essential to avoid disease development. It would be necessary to examine the patterns and mechanisms associated with the massive and reiterative introduction of a microbial pest control agent. The effect of inundative releases of biopesticide formulations containing Penicillium frequentans for the control of Monilinia spp. populations, and the effect on fruit surface microbiota on 18 stone fruit field experiments located in four European countries for more than two crop seasons against brown rot were studied. P. frequentans was monitored after application in order to assess whether it was persistent or not in the environment. Hydrolysis of fluorescein diacetate and denaturing gradient gel electrophoresis were used to study the effects of P. frequentans on fungal and bacterial non-target populations on fruit surface. The effect of P. frequentans formulations on the populations of Monilinia spp. on fruit was also assessed in different orchards. P. frequentans population on stone fruit surfaces showed ranged from 100 to 10,000 CFU cm-2, and postharvest recovered populations were more than 10-100-fold higher than preharvest recovered populations. The population of P. frequentans varied among orchards and years, rather than by the type of formulation. P. frequentans formulation reduced Monilinia spp. population and brown rot and latent infections caused by this pathogen both before and at harvest, while stabilizing or increasing antagonist populations and avoiding non-target microorganisms. However, fungicides reduced significantly the microbial activity on nectarine surfaces., This work was carried out with the financial support from BIOCOMES project (EU FP7 612713).