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31.
2006至2008年的夏季,从黄山景区海拔500-1600m处,采集至少23个属的631株禾本科植物,通过镜检,其中的内生真菌检出率为39%.内生真菌的分布与宿主植物的种类、宿t植物的地理分布类型等有关,拂子茅植物的检出率高达67%.在所调查的6个地理分布类型中,内生真菌大量分布在北温带分布的植物类型中.从短柄草中发现了香柱菌(Epichloe sp.),其子座等形态学特征与欧洲菌株存在很大差异,这是我国新报道的第2例有性型内生真菌. 相似文献
32.
历史文化名城中古树名木的价值分析——以丽江古城为例 总被引:1,自引:0,他引:1
中国历史文化名城、世界文化遗产——丽江古城,是人居环境的典范,分布在丽江古城中的古树名木是园林植物文化的瑰宝。从丽江古城古树名木的调查统计入手,深入分析历史文化名城中古树名木的生态价值、文化价值和旅游价值,以期为传承和创新园林植物文化提供科学依据和决策参考,对建设生态文明城市和有效保护世界遗产具有重要研究意义。 相似文献
33.
植物在园林造景中的作用 总被引:8,自引:0,他引:8
植物是构成园林景观的要素之一,它具有创造、组织、拓展园林空间的造景功能和观赏功能;植物造景须从造景需要出发,选择合理的配置方法。 相似文献
34.
《Communications in Soil Science and Plant Analysis》2012,43(7-8):1139-1156
Abstract This study evaluated the effects of four different kinds of compost: pea–rice hull compost (PRC), cattle dung–tea compost (CTC), hog dung–rice hull compost (HDR), and hog dung–sawdust compost (HDS). These types of compost differ in nitrogen composition and in the dry matter yield and nutrient accumulation [nitrogen (N), phosphorus (P), potassium (K)], of rice plants. The rice (Oryza sativa L.) plants were planted in an Oxisol soil. Plants were cultivated in pots, which contained 3 kg of soil, mixed with the four different composts (PRC, 404 g; CTC, 395 g; HDR, and HDS, 450 g) and chemical fertilizer (CHEM) (N:P2O5:K2O=120:96:72) The residual effect was studied after the crop was harvested. All treatments were replicated four times, with a randomized complete block design. The nutrient concentrations in the root, leaf sheath, leaf blade, stalk, and grain were analyzed at different growth stages. After the first crop, the dry matter yield and the amount of N, P, and K absorbed from the CTC or HDS treatments were higher than those of the other treatments, at the most active tillering stage. The growth and nutrient accumulation of rice plants given the PRC treatment were higher than those given the CHEM treatment at the heading stage or the HDR treatment at the maturity stage. In the second crop, the dry matter yield from the PRC, CTC, and HDR treatments was higher than from the other treatments. The nutrient accumulation of the rice plants was positively correlated with the dry matter yield. The residual effect of the HDS compost was the least among all four composts. 相似文献
35.
《Communications in Soil Science and Plant Analysis》2012,43(17-18):2673-2687
Mandated processing of waste by‐products in the United States has inspired national interest in addressing the effectiveness of using composted biosolids and yard trimmings to grow containerized plants. Diamond bay Chinese evergreen (Aglaonema ‘Diamond Bay’) was transplanted in containers filled with one of eight formulated media (components added by volume). Medium 1 was a standard mix commonly used in Aglaonema production (5:2:3 peat–vermiculite–perlite); medium 2 was formulated on site to contain peat–bark–stalite–rice hulls–coir (2:2:3:1:2); media 3 and 4 contained 40% biosolid–yard waste compost instead of peat and with or without 20% stalite, respectively; and media 5, 6, 7, and 8 were commercially formulated to contain peat–bark–perlite–rice hulls–coir (4:1.5:2.5:1:1, 4:1.5:2.5:1:1, 4:2:2:1:1, and 3.0:2.5:2:1:1.5, respectively). Physical and chemical properties of the eight media were in ranges 50–65% container water‐holding capacity, 2.9–7.8% air‐filled porosity, 55–80% moisture (w/w), 0.11–0.37 g·cm3 bulk density, 0.34–0.96 g·cm3 particle density, 4.2–7.2 pH, 0.12–4.4 dS·m?1 electrical conductivity (EC), 27.3–54.5 meg/100 g cation exchange capacity (CEC), 17.9–39.0% carbon (C), and 0.22–1.7% nitrogen (N). Medium 4 (40% compost) had 5.5 times more ammoniacal N (NH4‐N) and 1.7 times more nitrate N (NO3‐N) than that of the standard commercial mix. At week 8, plants grown in media 2 and 5 were 8.9% to 9.5% taller than plants grown in medium 1 (commercial standard). At week 16, there were no significant differences in plant heights or growth indices among media. At week 24, there were no significant differences in plant height, growth index, visual quality, shoot dry weight, and root dry weight among media. However, cumulative phosphorus (P) leaching from media 1, 4, and 5 was significantly more than leaching from media 2 and 8. This study suggests that compost may serve as a horticulturally suitable and cost‐effective alternative to peat‐based media for Aglaonema production. 相似文献
36.
寄主诱导的基因沉默(host-induced gene silencing,HIGS)以病原菌生长发育、产孢繁殖、侵染或致病过程中的关键基因作为靶点,在寄主植物中表达针对靶基因的RNAi构建体,在病原菌侵染植物的过程中,摄入相应的ds RNA或si RNA分子,通过识别、结合特异核苷酸序列,干扰病菌靶基因表达,从而抑制病菌侵染和扩展,使植物表现抗病。这项技术为培育基于病原菌特异序列的植物抗病性奠定了基础,显示了巨大的应用潜力。本文综述了利用HIGS技术提高植物真菌病抗性的最新研究进展,总结了国内外利用这项技术改良植物真菌病害抗性的主要策略、技术路线,展望了发展应用前景。 相似文献
37.
38.
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
39.
浙江海岛乡土树种资源调查研究 总被引:3,自引:0,他引:3
在植物、植被和林业调查的基础上,筛选出适应海岛生境的395个乡土绿化树种,分析了树种资源的基本特点,并根据立地条件分5类阐述了树种选择依据和资源现状,最后,提出了乡土树种资源开发利用意见。 相似文献
40.