Effect of electric impulse on sporocarp formation of ectomycorrhizal fungusLaccaria laccata in Japanese red pine plantation
We examined the effect of electric impulses on sporocarp formations of ectomycorrhizal fungus in a Japanese red pine (Pinus densiflora) plantation.Laccaria laccata was the dominant species in this study plantation. Spatial distribution concentrated in the electric impulse treatment zone, and recorded a markedly larger number of sporocarps compared with untreated control plots. The effect of electric impulses was also recognized onL. laccata fruiting with a mycorrhizal sapling in a pot. Sporocarp production ofL. laccata was strongly promoted by the electric impulse in experiments bothin vivo natural plantation stands andin vitro pot saplings. Our work indicates the possibility of enhancement of sporocarp production of the mycorrhizal fungi with electric impulses in the nursery and plantation.
Culture maturity of Lentinula edodes on sawdust-based substrate in relation to fruiting potential.
Culture maturity assessment can be used to control fruiting body flush timing. Culture maturity of sawdust-based substrate was evaluated by using oak mushroom, (Lentinula edodes (Berk.) Pegler). The influence of substrate water potential () on the growth and fruiting of three genotypes of L. edodes was also investigated. Glucosamine content revealed a peak at the fruiting body senescent stage. Glucosamine increased steadily to the sporophore senescent stage, and sharply declined at crop treatment. Lipid phosphate and ergosterol contents peaked at pinning and button break stages, respectively. Therefore lipid phosphate and ergosterol contents would be considered as the convenient measurement for judging culture maturity and fruiting potentials. The substrate pH values before inoculation and on the fruiting stage were varied from 6.3 to 4.0. This pH changes were detected as changes in color from bluish purple to yellow by direct bromphenol blue(BPB) spraying, and shown a good correlation with fruit body yield of the 1 st flush. Concerning water potential of the cultures, a slight reduction of water potential, -0.5MPa, stimulated mycelial and colony growths on liquid, agar and sawdust-based substrates. The water potential of well-colonized matured substrate was -0.7MPa and -4.0MPa, before and after the fruiting, respectively. Excellent water providing capacity (higher ) is expected to well-matured cultures with a high density of mycelial colonization. Also, the substrate water potential significantly affected by the interaction between genotypes and spawn run time.
Geographic And Environmental Influence On Maya Settlement Patterns Of The Northwest Yucatan: An Explanation For The Sparsely Settled Western Cenote Zone
Most settlement pattern research and GIS analysis of the ancient Maya of the Northern Yucatan have focused on water availability in a dry landscape where cenotes are often the only water source. While water is of paramount importance, permanent settlement secondarily requires farmable soil, a resource often as precious as water in many parts of the Yucatan. The dynamics between these resources reveal areas of ideal settlement and more challenging landscapes for which the Maya developed strategies to overcome environmental conditions. A region of the southwest "Cenote Zone", however, appears to have presented the ancient Maya with insurmountably poor environmental conditions despite abundant water resources. The lack of dense population and stone architecture in this area emphasizes the lack of a simple correlation between cenotes and settlement. This thesis uses GIS analysis to identify and explore such problematic settlement areas to better understand the factors and complexities involved in the more successful settlements of neighboring regions. iv This work is dedicated to my late father, who first introduced me to the Mundo Maya through a visit to the ruins of Tikal at the age of nine, and who instilled in me strength, curiosity, and a love for exploring the world. v ACKLOWLEDGEMENTS I'd like to acknowledge Dr. Arlen Chase and Dr. Diane Chase for providing such outstanding opportunities and instruction, and for leading by example both in the field and in the classroom. Dr. John Walker for his eye-opening perspectives, GIS instruction, inspiring hard-working attitude, and patience in the field. Dr. Clifford Brown and Dr. Walter Witschey for their invaluable correspondence and for their contributions to mapping and GIS data of Maya sites.