“Speck rot caused by Phacidiopycnis washingtonensis and Sphaeropsis rot caused by Sphaeropsis pyriputrescens are two recently reported postharvest
diseases of apple. Infection by these two pathogens occurs in the orchard but remains latent before harvest. Symptoms develop after harvest and are similar to those of gray mold caused by Botrytis cinerea. Accurate diagnosis of these diseases is important during the fruit inspection process, particularly in the instance of fruit destined for export. Early near-harvest detection of latent infections in apple fruit is an important step to implement relevant pre- and postharvest measures for disease control. The aim of this study was to develop polymerase chain reaction (PCR) assays for diagnosis and early detection of latent infections
of apple fruit by P. washingtonensis and S. pyriputrescens. SB203580 inhibitor Species-specific primers based on the ribosomal DNA internal transcribed spacer region were designed for use in PCR assays. Conventional and real-time PCR assays were developed and validated using fruit inoculated with P washingtonensis, S. pyriputrescens, or B. cinerea and compared with identifications using traditional isolation-based assays. For wound-inoculated fruit, the PCR assays consistently provided the correct identification of the pathogen used as the inoculant in 6 h of processing time, compared with 5 to 6 days using culture-based methods. Real-time PCR assays effectively detected latent see more infections in symptomless stem and calyx tissues of fruit that were inoculated with the pathogens in the orchard during the growing season. The PCR assays provide a rapid, accurate method for diagnosis and early detection of these diseases.”
“Terrestrial ecosystems represent a major sink for
ozone (O-3) and also a critical control of tropospheric O-3 budget. However, due to its deleterious effects, plant functioning is affected by the ozone absorbed. It is thus necessary to both predict total ozone deposition to ecosystems and partition the fluxes in stomatal and non-stomatal Rabusertib pathways. The Surfatm-O-3 model was developed to predict ozone deposition to agroecosystems from sowing to harvest, taking into account each deposition pathways during bare soil, growth, maturity, and senescence periods. An additional sink was added during senescence: stomatal deposition for yellow leaves, not able to photosynthesise but transpiring. The model was confronted to measurements performed over three maize crops in different regions of France. Modelled and measured fluxes agreed well for one dataset for any phenological stage, with only 4% difference over the whole cropping season. A larger discrepancy was found for the two other sites, 15% and 18% over the entire study period, especially during bare soil, early growth and senescence.