BackgroundA variety of spore discharge processes have evolved among the fungi. Those with the longest ranges are powered by hydrostatic pressure and include “squirt guns” that are most common in the Ascomycota and Zygomycota. In these fungi, fluid-filled stalks that support single spores or spore-filled sporangia, or cells called asci that contain multiple spores, are pressurized by osmosis. Because spores are discharged at such high speeds, most of the information on launch processes from previous studies has been inferred from mathematical models and is subject to a number of errors.Methodology/Principal FindingsIn this study, we have used ultra-high-speed video cameras running at maximum frame rates of 250,000 fps to analyze the entire launch process in four species of fungi that grow on the dung of herbivores. For the first time we have direct measurements of launch speeds and empirical estimates of acceleration in these fungi. Launch speeds ranged from 2 to 25 m s−1 and corresponding accelerations of 20,000 to 180,000 g propelled spores over distances of up to 2.5 meters. In addition, quantitative spectroscopic methods were used to identify the organic and inorganic osmolytes responsible for generating the turgor pressures that drive spore discharge.Conclusions/SignificanceThe new video data allowed us to test different models for the effect of viscous drag and identify errors in the previous approaches to modeling spore motion. The spectroscopic data show that high speed spore discharge mechanisms in fungi are powered by the same levels of turgor pressure that are characteristic of fungal hyphae and do not require any special mechanisms of osmolyte accumulation.

Fungi are ubiquitousthey are found in any conceivable environment, i.e., both aquatic and terrestrial habitats. They remain one of the most diverse groups of organisms on Earth. Because fungi are heterotrophic, they obtain their nutrients by colonizing their substrates with a vegetative mass of hyphae called mycelium. These hyphae secrete enzymes that digest nutrients locked in colonized substrates, after which the nutrients are then absorbed by the hyphae. Not only do hyphae constitute the mycelium of fungi, but they also form other structuresmycelial strand, mycelial cords, and rhizomorphsthrough which fungi are able to spread in their environment in search of new substrates to colonize. The aim of this present paper is to explore the structure of mycelial cords and rhizomorphs. Rhizomorphs are among the most complex organs produced by fungi. They are root-like structures constituted by a series of differentiated tissues each with distinctive hyphal type, orientation, size, and function. Thus, rhizomorphs are produced as a result of a coordinated growth of millions of bundled hyphae. Rhizomorph-forming fungi thrive in nutrient-poor environment and are known to cause devastating destruction to homes and plantations. Because rhizomorphs serve as exploratory organs, and they enhance the survival of rhizomorph-forming fungi in plantations and homes, farmers, homeowners, attorneys, and even mycologists and plant pathologists, need to understand and appreciate their potential to wreak havoc that results in huge annual financial losses.

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The biotechnological potential of using monoand co-cultures of Aspergillus niger van Tieghem and Trichoderma viride Pers ex Fr. to enhance the protein content of cassava (Manihot esculenta Crantz) peels by solid substrate fermentation.

This study evaluated the microbiological contamination of cabbage, lettuce, and scallions sold  in Abura and Kotokuraba markets in Cape Coast, Ghana. These vegetables were analyzed for the presence and levels of microorganisms using standard microbiological procedures. Re­sults revealed bacterial and fungal contaminations of the vegetables from Abura and Kotoku­raba markets. Mean bacterial counts recorded in Nutrient Agar, for example, from Kotokuraba market were 1.93x108, 1.23x108, and 1.17x108 cfu/ml for cabbage, lettuce and scallion, respec­tively, higher than mean bacterial counts recorded from Abura market at 9.9x107, 2.8x107, and 6.60x107 cfu/ml for cabbage, lettuce and scallion, respectively. Conversely, the mean fungal counts for cabbage, lettuce and scallion were higher at Abura market than Kotokuraba market. Bacteria isolated from the vegetables include Escherichia coli, Enterobacter spp., Klebsiella spp., Salmonella spp., Serratia marcescens, and Staphylococcus, whereas fungi of the genera Aspergillus, Candida, Fusarium, Penicillium, and Rhodotorula were isolated. These results indicate that the vegetables are significantly contaminated, and have poor microbiological quality that could potentially result in outbreak of foodborne illnesses. Contaminations of the vegetables were due to poor pre- and post-harvest handling practices. The implications of findings of this study on tourism and hospitality industries in Cape Coast are discussed. Keywords: cabbage, food microbiology, foodborne microorganisms, Ghana, lettuce, scallion