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51.
艾比湖湿地盐生植物区系研究 总被引:1,自引:2,他引:1
对艾比湖湿地盐生植物区系和常见群落的土壤盐分特征进行了分析。结果表明:艾比湖湿地盐生植物物种多样性较为丰富,共有31科73属144种,分别占新疆盐生植物39科128属358种的79.5%、57.0%和40.2%,占中国盐生植物73科239属566种的42.5%、30.5%和25.4%;艾比湖湿地盐生植物地理成分在科的分布有4个类型4个变型;属的分布有9个类型7个变型,其中古地中海成分明显,没有区系特有成分。常见盐生植物群落冠下土壤盐分含量均显著低于裸地,能有效改良盐碱地。 相似文献
52.
甘肃生态环境复杂多样,孕育了丰富的药用植物资源和大量独特的地道药材,中药材资源、产量均居全国前列。但由于投入严重不足、科技力量薄弱、研发能力较低、产品质量不高、开发保护和基地建设滞后等原因,资源优势没有形成产业优势。只有通过加大管理和保护力度,稳定和丰富中药材资源;加大扶持、服务、技术公关和资金投入力度,推进规范化种植和基地建设,促进中草药规模化、产业化;加强地道中药材原产地保护,提升甘肃中药材产业竞争力,实现甘肃药用植物资源的永续利用和可持续发展。 相似文献
53.
Specialty materials such as essential oils, pharmaceuticals, colorants, dyes, cosmetics and biocides are obtained from plants. Many species of medicinal and aromatic plants (MAPs) are cultivated for such industrial uses, but most are still wild collected. The need for renewable sources of industrial products as well as the need to protect plant biodiversity creates an opportunity for farmers to produce such crops. The production of plants as raw material for fine chemicals is different than cultivation of ornamental or food crops. This review attempts to give an overview of the use of MAPs in various industries, as well as trends in the various markets involved. Economic and regulatory issues relevant for such uses of MAP material are also discussed, with a focus on the situation in the European Union. The aim is to provide information to potential producers to help identify interesting MAPs for cultivation. 相似文献
54.
An experiment was undertaken to determine the herbage biomass and oil production of thyme (Thymus vulgaris Linn.) and hyssop (Hyssopus officinalis Linn.) in 2003 and 2004 in the semi-arid region of Khorasan in Iran. The experiment was a split plot with three irrigation intervals as main plots and three planting densities as subplots, all of which replicated three times. Irrigation intervals consisted of 7, 14, and 21 days for both crops and planting densities of 6.6, 8, and 10 (plants m−2) for thyme and 5, 6.6, and 8 (plants m−2) for hyssop. Different planting densities were employed by changing planting distances on cultivation rows. Herbage biomass and oil production of shoots, harvested at flowering were measured as annual production of each crop. Irrigation intervals did not change total harvested herbage biomass and oil production of both crops. Averaged across both years of the experiment, thyme produced higher oil than hyssop. Both crops produced higher biomass and oil in the second year of the experiment compared to the first year. While thyme plants biomass and oil production were lower at the highest planting density, hyssop plants showed no response to planting density. Herbage biomass and oil production of hyssop did not show a clear trend in response to interaction of irrigation intervals and planting densities in both years of the experiment. Our results showed that there is a high potential for saving water through longer irrigation intervals (e.g. 14 days) using locally adapted plants in the semi-arid conditions of Khorasan. These crops serve as alternative sources of income in dry years. 相似文献
55.
56.
一种新的药用真菌--瓦尼木层孔菌(杨黄) 总被引:1,自引:0,他引:1
瓦尼木层孔菌(杨黄)是一种新的药用真菌发现在吉林省长白山地区,它属于担子菌门的锈革孔菌科。由于它生长在杨树上,且子实层表面为黄色,故当地人称之为杨黄。本文对该菌进行了详细介绍。 相似文献
57.
58.
The effects of cytokinins, carbohydrate sources and cold pretreatment on the conversion of protocorm-like bodies (PLBs) to shoots were investigated for the enhancement of micropropagation of Dendrobium huoshanense C.Z. Tang et S.J. Cheng, an endangered medicinal plant in China. The effects of cytokinins and carbohydrate sources on the conversion of PLBs to shoots depended on their types and concentrations. The best results in terms of shoot development from PLBs occurred on 1/2 MS medium supplemented with 20 μM kinetin and 10 g l−1 maltose. Cold pretreatment at 10 °C for 1–2 weeks significantly enhanced the conversion of PLBs to shoots, and over 1300 shoots were obtained from one gram of PLBs after 3 months of culture. The developed shoots were rooted on growth regulator-free MS medium supplemented with 8 g/l banana paste to give complete plantlets, which were successfully acclimatized with a survival rate of approximately 65%. The results indicate that a suitable cold pretreatment (10 °C for 1 week) followed by the use of 20 μM kinetin and 10 g/l maltose in 1/2 MS medium would produce a large number of shoots from PLBs for plantlet regeneration of D. huoshanense. 相似文献
59.
60.
苍耳等药用植物提取物对小菜蛾的拒食作用和产卵忌避效果 总被引:16,自引:0,他引:16
室内采用叶碟法,研究苍耳(Xanthium sibiricumPetril)等8种药用植物乙醇提取物对小菜蛾(Plutel-la xylostella)的拒食和产卵忌避活性。结果表明,苍耳(果实)、雷公藤(根)和商陆(根)乙醇提取物对小菜蛾4龄幼虫的取食均有较强的抑制作用,选择性拒食率分别为86.16%、49.06%和43.82%;非选择性拒食效果仍以苍耳(果实)提取物最好,达45.23%。选择性产卵忌避率以雷公藤(根)提取物为最高(69.52%),其次是苍耳(果实)和山苍树(枝叶)提取物,分别为62.50%和57.72%,雷公藤(根)、商陆(根)、窃衣(茎叶)和苍耳(果实)的非选择性产卵忌避作用均在77%以上。苍耳和雷公藤提取物在对小菜蛾的拒食和产卵忌避的各测试中,均表现较强活性。 相似文献