Global distribution of two fungal pathogens threatening endangered sea turtles

This work was supported by grants of Ministerio de Ciencia e Innovación, Spain (CGL2009-10032, CGL2012-32934). J.M.S.R was supported by PhD fellowship of the CSIC (JAEPre 0901804). The Natural Environment Research Council and the Biotechnology and Biological Sciences Research Council supported P.V.W. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. Thanks Machalilla National Park in Ecuador, Pacuare Nature Reserve in Costa Rica, Foundations Natura 2000 in Cape Verde and Equilibrio Azul in Ecuador, Dr. Jesus Muñoz, Dr. Ian Bell, Dr. Juan Patiño for help and technical support during samplingPeer reviewedPublisher PD

Progress and Research Needs of Plant Biomass Degradation by Basidiomycete Fungi

Peer reviewe

QTL mapping for brown rot (Monilinia fructigena) resistance in an intraspecific peach (Prunus persica L. Batsch) F1 progeny

Brown rot (BR) caused by Monilinia spp. leads to significant post-harvest losses in stone fruit production, especially peach. Previous genetic analyses in peach progenies suggested that BR resistance segregates as a quantitative trait. In order to uncover genomic regions associated with this trait and identify molecular markers for assisted selection (MAS) in peach, an F1 progeny from the cross "Contender" (C, resistant) 7 "Elegant Lady" (EL, susceptible) was chosen for quantitative trait loci (QTL) analysis. Over two phenotyping seasons, skin (SK) and flesh (FL) artificial infections were performed on fruits using a Monilinia fructigena isolate. For each treatment, infection frequency (if) and average rot diameter (rd) were scored. Significant seasonal and intertrait correlations were found. Maturity date (MD) was significantly correlated with disease impact. Sixty-three simple sequence repeats (SSRs) plus 26 single-nucleotide polymorphism (SNP) markers were used to genotype the C 7 EL population and to construct a linkage map. C 7 EL map included the eight Prunus linkage groups (LG), spanning 572.92 cM, with an average interval distance of 6.9 cM, covering 78.73 % of the peach genome (V1.0). Multiple QTL mapping analysis including MD trait as covariate uncovered three genomic regions associated with BR resistance in the two phenotyping seasons: one containing QTLs for SK resistance traits near M1a (LG C 7 EL-2, R2 = 13.1-31.5 %) and EPPISF032 (LG C 7 EL-4, R2 = 11-14 %) and the others containing QTLs for FL resistance, near markers SNP_IGA_320761 and SNP_IGA_321601 (LG3, R2 = 3.0-11.0 %). These results suggest that in the C 7 EL F1 progeny, skin resistance to fungal penetration and flesh resistance to rot spread are distinguishable mechanisms constituting BR resistance trait, associated with different genomic regions. Discovered QTLs and their associated markers could assist selection of new cultivars with enhanced resistance to Monilinia spp. in fruit

Effects of litter type, origin of isolate, and temperature on decomposition of leaf litter by macrofungi

The dependence of hyphal growth and litter decomposition on litter type and incubation temperature used as substratum were compared for litter-decomposing macrofungi originating from subtropical (ST), cool temperate (CT), and subalpine forests (SA) in Japan. In the first series of pure culture decomposition tests using a total of 39 litter types as substrata inoculated with six fungal isolates from the three climatic regions, the fungal decomposition of litter was negatively affected by the content of acid-unhydrolyzable residues (AUR) or extractives and positively by N content in the litter. Secondly, cross-inoculation tests were performed to examine the mass loss of leaf litter of broad-leaved trees from ST, CT, and SA, each inoculated with three Mycena species from the three climates and incubated at seven temperatures between 5 and 35 °C. Fungal isolate, litter type, incubation temperature, and their interactions significantly affected the mass loss of litter during the incubation. The greatest values of mass loss were found at 20 or 25 °C, and were generally consistent with the optimum temperatures of colony diameter growth rate of these isolates. Isolates from cooler regions were more sensitive to higher temperature than isolates from warmer regions. The decomposition of recalcitrant compounds (as acid-unhydrolyzable residues, AUR) by Mycena sp. from ST was also affected by litter type and incubation temperature, but the degree of selective decomposition of AUR relative to other components, such as cellulose, was insensitive to the range of temperature tested

Decomposing ability of diverse litter-decomposer macrofungi in subtropical, temperate, and subalpine forests

An integrative survey was conducted on the ability of litter-decomposing macrofungi (LDM) from forests of different climatic regions to decompose litter materials and recalcitrant compounds in the litter under pure culture conditions. A total of 75 isolates in six families of LDM from subtropical, cool temperate (CT), and subalpine (SA) forests in Japan were tested for their ability to decompose a total of eight litter types that are major substrates for macrofungi at each site. The mass loss of the litter (% original mass) during incubation for 12 weeks at 20 °C ranged from −3.1 % to 54.5 %. Macrofungi originated from forests of different climatic regions exhibited similar decomposing abilities, but the SA isolates caused negligible mass loss of Abies needles, possibly due to inhibitory compounds. Decomposing activity for recalcitrant compounds (as acid-unhydrolyzable residues, AUR) was found in many macrofungal isolates. The isolates of Marasmiaceae were generally more able to cause selective decomposition of AUR than those of Mycenaceae and to decompose AUR in partly decomposed materials. The isolates of Xylariaceae had lower ligninolytic activity than those of Basidiomycetes. The AUR mass loss caused by CT isolates was significantly lower in nitrogen-rich beech litter than in its nitrogen-poor counterpart, suggesting a retarding effect of nitrogen on AUR decomposition, which was obvious for Mycenaceae. The effect of fungal family was generally more significant than that of litter type, suggesting that possible changes in the composition of fungal assemblages influence their functioning more than changes in the quality of substrates

Effects of continuous 0.3 ppm ozone exposure on decay development and physiological responses of peaches and table grapes in cold storage

Continuous ozone exposure at 0.3 ppm (v/v) (US-OSHA Threshold Limit Value for short term exposure) inhibited aerial mycelial growth and sporulation on `Elegant Lady' peaches wound inoculated with Mondinia fructicola, Botrytis cinerea, Mucor piriformis, or Penicillium expansum and stored for 4 weeks at 5 degreesC and 90% relative humidity (RH). Aerial growth and sporulation, however, resumed afterward in ambient atmospheres. Ozone exposure did not significantly reduce the incidence and severity of decay caused by these fungi with the exception of brown rot. Gray mold nesting among `Thompson Seedless' table grapes was completely inhibited under 0.3 ppm ozone when fruit were stored for 7 weeks at 5 degreesC. Gray mold incidence, however, was not significantly reduced in spray inoculated fruit. Continuous ozone exposure at 0.3 ppm increased water loss after 5 weeks of storage at 5 degreesC and 90%, RH in `Zee Lady' peaches but not after 4 weeks of storage in `Flame Seedless" grapes. Respiration and ethylene production rates of `O'Henry' peaches were not affected by previous exposure to 0.3 ppm ozone. In every test, no phytotoxic injuries of fruit tissues were observed in ozonated or ambient atmosphere treatments. (C) 2002 Elsevier Science B.V. All rights reserved