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61.
The Edible Mushrooms of Madagascar: An Evolving Enigma. This paper on the most significant edible wild mushrooms of Madagascar is organized in the following four categories: (1) mushrooms of introduced eucalypt plantations, (2) mushrooms of introduced pine plantations, (3) mushrooms of native forests and woodlands, and (4) mushrooms found in fields, agricultural waste and other altered, non–forest habitats. Eucalyptus robusta plantations yield by far the bulk of edible mushrooms that are sold, especially species of Russula and Cantharellus. Some Suillus species of northern hemisphere origin have been introduced with pine plantations and are locally important, forming the basis of a small canning industry. In native woodland areas on the central plateau, several ectomycorrhizal mushrooms—very similar to those on the African mainland—are collected and consumed. With the exception of the widely marketed Cantharellus platyphyllus ssp. bojeriensis, these are only of local importance in the villages and smaller markets of the area. Denser forests in the mountains or on the east coast as well as manmade habitats such as fields, pastures, and agricultural wastes are searched for saprobic mushrooms of various types. Some of these saprobic mushrooms show considerable potential for cultivation. The variety of ectomycorrhizal mushrooms found in eucalypt plantations is unprecedented outside of Australia and, for the most part, do not appear to be of Australian origin. Possible reasons for this are briefly discussed. Two economically important species, Russula prolifica sp. nov. and R. edulis sp. nov., are newly described.  相似文献   
62.
Peptide immunotherapy using dominant T-cell epitopes is safer and more effective than conventional immunotherapy for the treatment of immunoglobulin E (IgE)-mediated allergic diseases. When allergenic T-cell epitope peptides are expressed in the edible part of transgenic plants, successful mucosal immune tolerance to these allergens may be attainable by the consumption of these plants. In this study, we generated transgenic rice seed that accumulated high concentrations (about 60 microg per grain) of polypeptide consisting of seven dominant human T-cell epitopes derived from the Japanese cedar pollen allergens, Cry j 1 and Cry j 2, in the endosperm. Oral administration of these transgenic rice seeds to B10.S mice before or after they were immunized with Cry j 1 holoprotein reduced not only their T-cell proliferative response to Cry j 1, but also their serum IgE levels, proving the efficacy of oral immunotherapy for the treatment of pollinosis.  相似文献   
63.
Summary Lipids are key components of all living cells. Acyl lipids and sterols provide the matrix of the biological membranes that both define the boundaries of cells and organelles, and act as sites for the trafficking of molecules within and into/out of cells. Lipids are also important metabolic intermediates and the most efficient form of energy storage that is available to a cell. It is the latter, energy-storing function that is of most relevance to this review. Storage lipids are accumulated in abundance in many of our most important crops, including maize, soybean, rapeseed, and oil palm, giving rise to a commerical sector valued at over $50 billion/year. Because the storage lipids of the major global oil crops have a relatively restricted composition, there is great interest in using all available breeding technologies, whether traditional or modern, to enhance the variation in lipid quality in existing crops and/or to domesticate new crops that already accumulate useful novel lipids. Over the past few decades, there has been a great deal of effort to manipulate fatty acid composition in order to produce novel lipids, especially for industrial applications. However, these attempts, many based on genetic engineering, have met with only limited commercial success-to date. More recently, there has been a resurgence of interest in the modification of both acyl and non-acyl lipids to enhance the nutritional quality of plant oils. In this review, we will examine the background to plant lipid modification and some of the latest developments, with a particular focus on edible oils.  相似文献   
64.
Southern Nigeria represents one of the richest zones of vegetational wealth of Nigeria. The land surface is dominated by plants under 200 m.a.s 1. Folk utilization of pteridophytes by the southern Nigerians was studied. The results of this survey display an interesting diversity and distribution of ferns and fern-allied plants used as medicines, food, cosmetics, and manure in southern Nigeria. The data were compiled from frequent field trips conducted in 40 local government areas (LGAs). A total of 36 plant species belonging to 22 families were identified. Plant specimens and information were collected directly from the local inhabitants in villages and periurban towns. Our literature survey showed little or no documentation of ethnobotanical studies on pteridophytes of this region. Therefore, the present communication serves to bridge the gap. Thus, these pteridophytes could provide a vital source for healthcare and economic revenue after appropriate pharmacological analysis by patents.  相似文献   
65.
Anoda cristata is a common weed used for food and medicine in central Mexico where it grows among field crops during the rainy seasons. People prefer robust, tender plants from the agricultural fields because these “develop better.” Hence, the plants are tolerated within the conventional agricultural activities and benefit indirectly from the improvements in the agrohabitat. People do not select individuals with specific morphological characteristics but rather they select for plants at the level of the habitat. This step may precede that of direct management of individual plants. It is possible that these differences in the level of interaction between humans and plants (i.e., within the ruderal and agrestal habitats) may promote morphological and genetic differences over time,
Etnobotánica de anoda cristata (Malvaceae) en México: Usos, Manejo y diferenciación poblacional en la Comunidad de Santiago Mamalhuazuca, Ozumba, estado de México
Resumen   Anoda cristata es una maleza muy común utilizada como medicina y alimento en el centro de México durante la época de lluvias La gente prefiere las plantas robustas y tiernas que crecen en los campos de cultivo porque se “desarrollan mejor.”Ahí, las plantas son toleradas dentro de las prácticas agrícolas tradicionales y se benefician indirectamente de las alteraciones que se hacen al agrohabitat. La gente no selecciona conscientemente individuos con características morfológicas específicas, sino que seleccionan a las plantas a nivel del hábitat. Este paso puede ser previo al manejo indirecto de individuos particulares. Es posible que estas diferencias en el nivel de interactión entre los hombres y las plantas (entre el hábitat ruderal y arvense) puede promover diferencias morfológicas y genéticas a través del tiempo.
  相似文献   
66.
Synchronously growing cells of nitrogen-fixing Synechococcus sp. Miami BG 043511 were harvested periodically and the capability for hydrogen photoproduction in closed vessels was measured under hydrogen production conditions. The capability for hydrogen photoproduction in cells was correlated with that of cellular carbohydrate content. Cells with a high carbohydrate content exhibited a high capacity for hydrogen production and those with low carbohydrate content exhibited low capacity for hydrogen production. Nitrogenase activity at the onset of incubation did not coincide with a capability for the cells to produce hydrogen during the subsequent incubation period. Interestingly, when cells with a high capacity for hydrogen photoaccumulation were incubated, alternate periods of hydrogen and oxygen accumulation were observed at 12 hour intervals. About 0.5 ml of hydrogen per ml of cell suspension was accumulated in flasks during the initial 12-h incubation period. These observations indicate that the use of synchronous culture can be one of the ways of provide materials suitable not only for basic studies but also for applied aspects of hydrogen photoproduction.  相似文献   
67.
A cyaA gene, encoding an adenylate cyclase, was isolated from a filamentous cyanobacterium, Spirulina platensis, by functional complementation of a cya mutant of Escherichia coli, defective in adenylate cyclase activity. The predicted gene product of cyaA contains a signal peptide-like domain, a putative sensor domain similar to the gene product of vsrA of Pseudomonas solanacearum, a putative membrane-spanning domain and an adenylate cyclase-like catalytic domain. Two other positive clones that complemented the E. coli mutant were isolated from the same cyanobacterium, suggesting that several cya genes are functioning in S. platensis.  相似文献   
68.
Indole acetic acid (IAA) production in Azospirillum brasilense strain Sp245 is controlled by a 85 MDa plasmid naturally present in this bacterium. In the presence of L-tryptophan, anthranilic acid production and almost no IAA production occurs in a derivative strain harbouring a Tn5-Mob insertion in the 85 MDa plasmid. Agrobacterium tumefaciens strain GM19023, upon transfer of Tn5-Mob labelled 85 MDa plasmid of A. brasilense Sp245, gains the ability to produce anthranilic acid.  相似文献   
69.
An investigation on the macrofungal diversity of the National Park “Appennino Lucano, Val D'Agri, Lagonegrese” (Basilicata, southern Italy) was carried out, together with an evaluation of wild edible mushrooms in agro-forest ecosystems and their possible exploitation as a new source of food and revenue in rural and under-developed areas of this region. An unpublished list of 249 mushroom taxa (229 Basidiomycota and 20 Ascomycota), mostly belonging to the genera Tricholoma, Tuber, Russula, Amanita, Boletus, Lactarius, Mycena, Agaricus, Clitocybe and Hygrophorus, growing in this important natural area is provided together with ecological characterization of the recorded specimens. Inonotus obliquus is a new record for Basilicata, while Mycena bresadolana is reported for the first time from southern Italy. The presence of Amaurodon mustialaënsis, an extremely rare species of the northern hemisphere reported for the first time on white fir, is noteworthy. Among the previous findings, 116 species of edible mushrooms are presented and discussed in view of their relative abundance and edibility.  相似文献   
70.
食用菌因其富含多种氨基酸及微量元素等物质,具有较高的营养价值和药用价值,越来越受到人们的关注和喜爱。我国作为最重要的食用菌生产国,食用菌生产规模不断扩大,产量也在逐年提高。为了更好地发展食用菌产业,迫切需要在传统的食用菌产业链,如优良品种选育及栽培生产中融入新技术。生物信息学作为一门研究分析生物生命结构的技术门类,通过运用数学、计算机科学等工具揭示了数据所蕴含的生物学意义,极大地促进了生命科学研究的发展,也为食用菌更深入的研究与应用提供了技术保障。本文从食用菌育种及种质资源调查、病虫害防治、基因组学、食用菌安全等几方面阐述了生物信息学在食用菌领域的具体应用,对生物信息学在食用菌及农业领域的发展进行了展望,以期为促进食用菌研究和生产发展提供参考。  相似文献   
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