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Among the biotic constraints of common mushroom (Agaricus bisporus) production, bacterial blotch is considered the most important mushroom disease in terms of global prevalence and economic impact. Etiology and management of bacterial blotch has been a major concern since its original description in 1915. Although Pseudomonas tolaasii is thought to be the main causal agent, various Pseudomonas species, as well as organisms from other genera have been reported to cause blotch symptoms on mushroom caps. In this review, we provide an updated overview on the etiology, epidemiology, and management strategies of bacterial blotch disease. First, diversity of the causal agent(s) and utility of high throughput sequencing-based approaches in the precise characterization and identification of blotch pathogen(s) is explained. Further, due to the limited options for use of conventional pesticides in mushroom farms against blotch pathogen(s), we highlight the role of balanced threshold of relative humidity and temperature in mushroom farms to combat the disease in organic and conventional production. Additionally, we discuss the possibility of the use of biological control agents (either antagonistic mushroom-associated bacterial strains or bacteriophages) for blotch management as one of the sustainable approaches for 21stcentury agriculture. Finally, we aim to elucidate the association of mushroom microbiome in cap development and productivity on one hand, and blotch incidence/outbreaks on the other hand.

Button mushrooms of Agaricus bisporus (Lange) Imbach are commercially cultivated under environmentally controlled conditions. In California they are the most economically important agricultural crop in Santa Clara and San Mateo counties, and also an important crop in 10 other counties. Trichoderma harzianum Rifai, biotype Th4, can reduce production by preventing formation of fruiting bodies. Biotype Th4 was previously detected and described in Canada (2), Pennsylvania, and Delaware. Unofficial reports suggest its presence in San Mateo County since 1995. Disease incidence and severity on the mushroom farms varied; some mushrooms became severely infected. Green epigeous mycelia and conidia were present on the casing layer resulting in empty patches. On some farms 30% of the production surface was infected during the peak of the epidemic. Initial identification of the species was made by isolating the fungus from the substrate and casing layer. Potato dextrose agar (PDA) cultures coincided with the cultural description of T. harzianum (1,3). Biotype assessments with standard procedures were conducted at Penn State, with polymerase chain reaction (PCR) amplification of total genomic DNA to screen the California isolates of T. harzianum. Random amplified polymorphic DNA (RAPD)-PCR analysis with 14 different primers indicated that they were the same RAPD haplotype as biotype Th4. The Horticultural Research Institute of Ontario relies on morphological observations from cultures grown on 2% MEA (malt extra agar) at 24°C under diffuse daylight to identify biotypes of T. harzianum (2), and microscopic characters of biotype Th4 were also positively confirmed on the California isolates. More than a parasite or pathogen, T. harzianum biotype Th4 is considered a weed mold of mushroom cultivation. The precise interaction is yet unknown. Modified Koch's postulates were confirmed with bags of commercial mushroom substrate (45 kg) inoculated by spraying 100 ml of a spore suspension (3.0 × 106 spores per ml) at filling, to give final concentrations of 103 to 108 spores per kg of compost. Treatments were T. harzianum biotype Th4, strain Th1, an unidentified isolate, control (distilled water only), and noninoculated. Eight replications per treatment were laid out in a randomized block design. Bags were subjected to standard mushroom cultivation practices. Biotype Th4 was reisolated from empty patches on the casing of all Th4 repetitions. Mean percent cover of the mold (therefore mushroom empty patches) was 30% for crops (flushes) 1 and 2, but individual bags varied from 15 to 90%. The mean percent cover in the other two treatments and in the controls was 0% for crops 1 to 4, therefore significantly different. Green mold was covering the total surface on all Th4 repetitions at third crop. No yields were recorded, but serious losses were obvious for the Th4 treatments. Green mold was not observed in the controls. References: (1) H. M. Grogan et al. Mushroom News 45:29, 1997. (2) D. L. Rinker et al. Mushroom World 8:71, 1997. (3) D. A. Seaby. Plant Pathol. 45:905, 1996.

Commercially available strains of hybrid white, hybrid off-white, and brown Agaricus bisporus mushrooms were compared for resistance to green mold caused by Trichoderma harzianum biotype 4 (Th4). Seven mushroom spawn strains were assessed for total weight of mushrooms (grams per 0.1 m2) with or without the addition of an aqueous Th4 spore suspension added at spawning time. Cropping studies were conducted at the Mushroom Research Center (Pennsylvania State University) to emulate commercial growing operations. Excessive spawn handling had no significant effect on development of green mold. Severity of green mold was related to time between infestation and green mold appearance, with more significant yield losses occurring when green sporulation was detected early in production. Significant differences in yield were measured among mushroom strains in response to Th4 infestation. Hybrid white strains were extremely susceptible, with a mean yield loss of 96%. Hybrid off-white strains exhibited intermediate susceptibility, with mean yield losses of 56 to 73%. Brown strains were highly resistant, with mean yield losses of 9 to 16%. From these findings, we report the existence of green mold resistance, with a continuum of resistance among spawn strains. The findings suggest use of brown strains to manage green mold outbreaks, particularly where benomyl resistance in Trichoderma spp. is a threat.

The late Permian is a transformative time, which ended in one of the most significant extinction events in Earth’s history. Fish assemblages are a major component of marine foods webs. The macroevolution and biogeographic patterns of late Permian fish are currently insufficiently known. In this contribution, the late Permian fish fauna from Kūmas quarry (southern Latvia) is described for the first time. As a result, the studied late Permian Latvian assemblage consisted of isolated chondrichthyan teeth ofHelodussp., ?Acrodussp., ?Omanoselachesp. and euselachian type dermal denticles as well as many osteichthyan scales of the Haplolepidae and Elonichthydae; numerous teeth ofPalaeoniscus, rare teeth findings of ?Platysomussp. and many indeterminate microremains. This ichthyofaunal assemblage is very similar to the contemporaneous Lopingian complex of the carbonate formation from the Karpėnai quarry (northern Lithuania), despite the fact that Kūmas samples include higher diversity and abundance in fossil remains. The differences in abundance of microremains could possibly be explained by a fresh water influx in the northeastern Zechstein Basin margin, which probably reduced the salinity of the sea water. The new data enable a better understanding of the poorly known late Permian fish diversity from the Lithuania-Latvia Region.

The radical surgery of the deep infiltrating endometriosis of the rectovaginal septum and the uterosacral ligaments with or without bowel resection can cause a serious damage of the pelvic autonomic nerves with urinary retention and the need of self-catheterization. Major goal of this review article is to compare different surgical techniques of deep infiltrating endometriosis and their follow-up results.The research strategy included the online search of databases [MEDLINE, EMBASE, SCOPUS] for the diagnosis of deep infiltrating endometriosis with the indication of an operative resection. The outcome of the follow-up terms were noticed and compared.All in all, 16 trials could be identified with included follow-up. In all patients at least single-sided resection of the uterosacral ligaments were performed. Follow-up was heterogeneous in all trials ranging from 1 to 92 months. Postoperative symptoms, such as dysmenorrhoea, pelvic pain, and dyspareunia were commonly described in the majority of trials. Nevertheless, a tendency towards lower comorbidity after nerve sparing resection of endometriosis could be observed.Identification of the inferior hypogastric nerve and plexus was feasible in the minority of trials. In comparison with non-nerve-sparing surgical technique, no cases of bladder self-catheterization for a long or even life time was observed, confirming the importance of the nerve-sparing surgical procedure.

Fresh mushroom compost is a byproduct of the edible mushroom (Agaricus bisporus) industry and represents the composted growing substrate that remains after a crop has been harvested to completion. Thirty samples were obtained from commercial mushroom farms in southeastern Pennsylvania and sent to a laboratory for analysis to determine plant nutrient content, bulk density, and particle size distribution of fresh mushroom compost. Fresh mushroom compost had an average pH of 6.6, with an average carbon:nitrogen ratio of 13:1. Organic matter content averaged 25.86% (wet weight), 146.73 lb/yard3 (wet volume) or 60.97% (dry weight). For the primary macronutrients, average total nitrogen content averaged 1.12% (wet weight), 6.40 lb/yard3 (wet volume) or 2.65% (dry weight), phosphorus measured 0.29% (wet weight), 1.67 lb/yard3 (wet volume) or 0.69% (dry weight), and potassium was 1.04% (wet weight), 5.89 lb/yard3 (wet volume) or 2.44% (dry weight). Average soluble salt content was 13.30 mmho/cm (wet weight basis). However, on a per acre basis, the calculated sodium absorption ratio of 0.38 was considered very low. The average bulk density of fresh mushroom compost was 574.73 lb/yard3 (wet volume basis), and 91% of the material measured ≤3/8 inch in diameter as determined on a wet weight basis. Overall, fresh mushroom compost is suitable as a natural organic fertilizer and soil amendment for agriculture and horticulture.

Agaricus bisporus (Lange) Imbach mushrooms, which are cultivated commercially under environmentally controlled conditions, are the most valuable crop in Pennsylvania. In August 2011, we first observed a mucoraceous mold colonizing primordia and mature basidiocarps of a new brown portabella strain of A. bisporus at two commercial mushroom farms in Chester County, PA. This strain is a hybrid between a commercial strain producing white basidiocarps and a brown wild type isolate of A. bisporus. Mushrooms mature in weekly “flushes”. By third flush, 25% of the production surface at both farms was colonized by a fast growing mycelium that was initially white, subsequently yellow to golden brown, and finally grayish. Mushrooms colonized by the mold showed pitting, discoloration, and necrosis. Two pure cultures of the mold were obtained by the hyphal tip method from mature, necrotic basidiocarps at each farm. These isolates were accessioned in the ARS Culture Collection (NRRL, Peoria, IL) as NRRL 54814 to 54815 and 54818 to 54819. The cultures produced abundant aerial sporangiophores that branched dichotomously on potato dextrose agar. Light microscopic examination revealed that each branch terminated in a globose, multispored sporangium with a conspicuous columella. Individual cultures of NRRL 54818 and 54819 produced large (175 to 250 × 200 to 250 μm), barrel-shaped, dark brown to black zygosporangia between opposed suspensors, indicating they were homothallic. Morphological and cultural characteristics of the mold matched the description of Syzygites megalocarpus (3), a member of the Mucorales reported to colonize diverse, mostly fleshy basidiomycetes (2), including cultivated matsutake (Tricholoma matsutake) in Korea (1). Molecular phylogenetic confirmation of the morphological identification was obtained by PCR amplifying and sequencing domains D1 and D2 at the 5′ end of the nuclear ribosomal large subunit (LSU rDNA). The four isolates shared an identical LSU rDNA allele. A search of the NCBI nucleotide database, using a partial LSU rDNA sequence from NRRL 54814 as the BLAST query, revealed that it shared 99.5% identity with AF157216.1, a reference isolate of S. megalocarpus NRRL 6288 (3). To assess whether cultures of S. megalocarpus could induce the disease, caps of portabella and white button mushrooms were inoculated with 3.7 × 106 sporangiospores. When incubated in moist chambers at 21 to 22°C with a 12-h photoperiod, disease symptoms developed in 2 to 3 days on portabella that included discoloration and pitting at the site of inoculation. S. megalocarpus was reisolated from the symptomatic mushrooms and produced a colony identical to the original. By comparison, white button mushrooms inoculated with S. megalocarpus, using the same method, only showed minor pitting and discoloration. Disease symptoms were not observed on mushrooms inoculated with water as a negative control. Although development of new commercial varieties derived using “wild” genetically diverse stocks is an effective way to introduce desirable traits into cultivated mushrooms, it carries the risk of introducing new diseases into the industry. References: (1) K.-H. Ka et al. Korean J. Mycology 27:345, 1999. (2) R. L. Kovacs and W. J. Sundberg. Trans. Il. State Acad. Sci. 92:181, 1999. (3) K. O'Donnell. Zygomycetes in culture. Palfrey Contributions in Botany. No. 2. Department of Botany, University of Georgia, Athens, 1979.

Habitat use estimates may be biased if the sampling design does not consider differences in a species' habitat use throughout a 24-hour period. We reviewed studies to examine the suitability of sampling designs in determining habitat use relative to a species daily activity pattern. Of 56 studies we reviewed, 22 presented data only from daylight sampling and 12 did not describe their methods with enough detail to determine when sampling occurred. Elk (Cervus elaphus) habitat use throughout the entire 24-hour period was different (P < 0.001) from that during diurnal hours. Managers should be cautious when implementing management strategies developed only from diurnal datasets