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41.
This study is part of an effort to improve the quality of dried shiitake mushrooms (Lentinula edodes) in accordance with consumer preference. Results are presented of a trend survey that examined the preferences of consumers using questionnaires combined with sensory evaluation. From the original preference (OP) survey, the distributions of OP divided by age class (AC) were statistically equal to the results obtained in 2000. The medians of OP for teenagers and twenties were “neutral” and “slightly like,” respectively. A firm preference change occurred between teenagers and those in their twenties. It is empirically realized that sensory intensity (SI) scores that were too high or too low led to a low hedonic preference (HP) score. The same tendency was seen for “neutralists” and “likers.” In addition, almost all distributions concerned with HP had no significant difference between 2000 and 2005; for example, that of SI divided by AC. These results showed that the preference for dried shiitake mushroom has been unaffected by the passage of the past 5 years. Dried shiitake mushrooms have been used from ancient times and for many dishes; therefore, the overall preference appears to have remained unchanged.  相似文献   
42.
次生阔叶林改建为食用菌原料林后的群落恢复和林分生长   总被引:6,自引:0,他引:6  
选择12年生林相较好的天然次生阔叶林,通过择伐更新和皆伐人促更新2种经营方式定向培育食用菌原料林。研究发现,择伐经营的经济效益较高,且有利于群落的快速恢复,经过7a的封育,林分蓄积量已达到择伐前的水平。皆伐人促更新获得的食用菌材虽较择伐利用高出40%左右,但因经营强度过大,保留的幼树受损严重而不利于伐后林木的生长与恢复,封育期内蓄积增长量分别为择伐更新和对照未经营区的64 7%和73 41%。动态监测结果显示,采用择伐和皆伐人促更新措施后群落恢复较快。疏伐后因透光度的急剧增加,阳性和中性树种大量侵入,地面芽植物和1年生植物的比例增高。到第7a时,高位芽植物的比例已接近未经营区的状态,乔、灌、草各层的物种多样性指数高于未经营的天然阔叶林,物种均匀度则与其相近。研究还发现,2种更新经营方式对土壤养分的损失较小,经过7a的恢复,林地土壤肥力已基本达到原有天然林水平。  相似文献   
43.
我国食用菌种质资源现状及其发展趋势   总被引:6,自引:0,他引:6  
对近年来我国食用菌种质资源调查现状和存在问题进行了分析总结,提出了要加大食用菌种质资源调查与保藏的科研投入,加强食用菌种质资源的鉴定评价、创新与利用研究,尽早确定国家知识产权战略,防止食用菌种质资源流失等发展对策.  相似文献   
44.
在丛生竹林下对不同基质配方和硒浓度菌棒进行埋棒栽培以及覆土方式栽培试验,结果表明,菌棒不同基质配方对竹荪产量及其营养成分有显著影响,而且三列浅沟形和双列龟背形2种覆土方式有利于提高竹荪产量。改良基质配方菌棒竹荪产量比常规配方提高约50%;在添加外源硒质量分数为0~2.0 mg/kg的浓度范围内,竹荪子实体产量先随着硒浓度的增加而逐渐增加后再有所降低,基质中添加1.5 mg/kg硒肥比不添加产量提高了195.30%。基质中添加硒质量分数为1.0~2.0 mg/kg的硒肥可以较显著地提高竹荪花的硒含量,其干物质中硒含量平均值从约2.50 mg/kg提高到8.05~13.30 mg/kg,外源硒肥利用率达到9.70%~15.36%。菌棒不同基质配方对竹荪子实体的粗蛋白及粗多糖含量有明显影响,改良配方竹荪蛋与竹荪花的粗蛋白含量是常规配方的1.21和1.29倍,其粗多糖含量是常规配方的4.81和1.35倍;基质中添加硒肥与不添加硒肥相比,竹荪蛋与竹荪花中粗蛋白含量分别增加了40.90%和14.30%。在硒质量分数为1.0 mg/kg的竹荪菌棒林下覆土栽培试验中,三列浅沟形覆土方式单位面积鲜竹荪蛋产量最高,为10.27 kg/m2;双列龟背形覆土方式单个菌棒的鲜竹荪蛋产量最高,达1.40 kg。三列浅沟形和双列龟背形2种覆土方式基质生物转化率分别为93.00%和94.14%,达到了较高水平。  相似文献   
45.
Aloe vera Linn. (Syn. Aloe barbadensis Mill; Gwar-patha in Hindi) belongs to family Liliaceae. The plant, for its medicinal properties, has commercial value. Some of the genotypes of Aloe vera are consumed as a vegetable and processed to make curry and other edible products. We report here on the development of an efficient method for rapid clonal propagation by shoot proliferation from axillary meristem(s) of selected germplasm of Aloe vera. Explants were pretreated with 0.1% aqueous solution of both streptomycin and bavistin separately, each for 15 min. These were surface sterilized with 0.1% aqueous solution of mercuric chloride (HgCl2) for 4–5 min and washed several times with autoclaved water. These were kept in a chilled, sterile antioxidant (200.0 mg L?1 of ascorbic acid, 50.0 mg L?1 of citric acid, and 25.0 mg L?1 of polyvinylpyrrolidone; PVP) solution and cultured on semi-solid Murashige and Skoog's (MS) medium. The bud explants produced multiple (10.3 ± 0.675/explant) shoots on MS medium containing 13.32 μM of 6-Benzylaminopurine (BAP) and 100.0 mg L?1 of ascorbic acid, 50.0 mg L?1 each of citric acid and PVP, with 25.0 mg L?1 each of arginine and adenine sulphate as additives. The shoots were further multiplied by (a) repeated transfer to fresh MS medium with additives + 13.32 μM BAP, and (b) subculturing on MS medium with a lower (4.44 μM) concentration of BAP. On MS medium containing 4.44 μM of BAP and additives, a maximum number (27.8 ± 0.63) of shoots were produced. In liquid MS medium with 4.44 μM of BAP, the rate of shoot multiplication increased and the vigor of the shoots improved. One hundred percent of the cloned shoots rooted under in vitro conditions on hormone-free half-strength MS salts containing 200.0 mg L?1 of activated charcoal at 32 ± 2°C. The cloned shoots treated with 2.46 mM of indole-3-butyric acid (IBA) or 2.473 mM of β-naphthoxyacetic acid (NOA) for 5 min rooted under ex vitro conditions in the greenhouse. The rooted plants were hardened in the greenhouse and stored under an agro-net house. The cloned plants were transferred under different field conditions at various sites in Western Rajasthan. These plants grew normally. The higher rate of shoot multiplication and easier approach of direct rooting and hardening make this method superior to the methods previously reported on cloning/tissue culture of Aloe species. From a single shoot bud, approximately 5000 plants can be produced within 180 days.  相似文献   
46.
Summary

Despite an encouraging trend in North America of growing interest across a range of disciplines in non-timber forest products (e.g., this volume), NTFP harvesters' knowledge and practices continue to be poorly understood and undervalued, if not ignored, both by research scientists and forestland policy-makers and managers. This article explores why NTFP harvesting suddenly emerged in North America as an “issue” in the early 1990s. Drawing from a three-year study of chanterelle mushroom harvesters on the Olympic Peninsula Biosphere Reserve (Washington, USA), we discuss a variety of forces which intersected in this period to bring NTFP harvesting to wider attention. Unfortunately, harvesters continue to be excluded as knowledgeable actors in, if not legitimate co-managers of, temperate forest ecosystems, resulting in both passive and active harvester resistance to research and management, a devaluing of local harvesting traditions, and missed opportunities for collaboration. We reluctantly conclude that despite “New Forestry” co-management rhetoric, given existing institutional barriers and positivist scientific categories, NTFP workers will likely remain excluded from active roles in temperate forest research and management-contributing in turn to the ongoing legitimacy crisis of public and private forest management entities.  相似文献   
47.
食用菌仿野生栽培在北京生态涵养发展区的作用与展望   总被引:2,自引:0,他引:2  
食用菌仿野生栽培能够有效利用人工林和天然林的大环境,产品天然优质。介绍了北京生态涵养发展区野生菌原始的生长状态、食用菌仿野生栽培的环境优势、仿野生栽培的作用、仿野生食用茵产品的优缺点、仿野生栽培适宜的种类、技术和发展前景等.  相似文献   
48.
采用多年多点进行菇木多树种育苗造林试验,3年来共育苗11hm2,营造试验林20.8hm2,示范林68.5hm2,树种19个。试验结果表明,选用水稻田育苗,通过间苗补植等措施,使合格苗达80%以上;选择山坡谷地的土层深厚、肥沃湿润地段造林,其成活率达85.8%~98.3%2年生桤木幼树,平均树高3.93m,平均地径4.1cm。初步看出桤木、杜英、马褂木是良好的速生菇木树种。  相似文献   
49.
珊瑚菌是由一些担子菌门真菌物种组成的,兼具食药用功能,从珊瑚菌中提取的活性物质具有抗菌、抗氧化、抗癌等多种作用,开发研究价值重大。本文对珊瑚菌的作用、生境、宏观微观特征及系统发育研究现状进行了概述,并对珊瑚菌在宜昌地区的发展前景进行了浅析,为珊瑚菌的驯化、研究和利用提供了一定的理论基础。  相似文献   
50.
千岛湖野菜植物有91种,隶属40科74属,研究千岛湖野菜植物的生长习性、适生条件、食用部位及其药用价值;阐述野菜植物的特点,提出千岛湖野菜植物的开发利用建议。  相似文献   
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