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21.
Lasmar Chaim J. Queiroz Antônio C. M. Rosa Clarissa Carvalho Nathália S. Schmidt Fernando A. Solar Ricardo R. C. Paolucci Lucas N. Cuissi Rafael G. Ribas Carla R. 《Landscape Ecology》2021,36(9):2583-2597
Landscape Ecology - Harmful effects of habitat loss and fragmentation can be detected across multiple spatial scales, yet most studies that aim to characterize these effects take place at a single... 相似文献
22.
Bonfim Fernando César Gonçalves Dodonov Pavel Cazetta Eliana 《Landscape Ecology》2021,36(9):2535-2547
Landscape Ecology - Anthropogenic land use and cover changes impact biodiversity worldwide. However, ecological groups are differently affected by landscape composition and configuration.... 相似文献
23.
茶条槭红色叶红色素稳定液的配比 总被引:1,自引:1,他引:0
采用3种有机酸加入适量的渗透剂配制混合稳定液,对茶条槭Acer ginnala Maxim.红色叶进行红色素稳定处理,在该混合稳定液的浸泡下,使茶条槭红色叶的红色素稳定,压制干燥后与新鲜叶片颜色相近。从而使茶条槭红色叶在材性方面取得较大的改善,扩大了压花画的材质资源。 相似文献
24.
磷素水平对不同大豆品种钾素吸收效率的影响 总被引:3,自引:2,他引:1
通过原子吸收分光光度计法研究了施磷量对不同大豆品种各器官及全株吸收钾素营养的影响,结果表明:施磷量对不同大豆品种植株及各器官钾素含量有较大影响.不同品种不同处理全株及各器官钾素含量从分枝期逐渐增加,开花期达到高峰,随后下降至成熟期;同一品种不同处理间钾素含量三个品种都是P10处理全株及各器官钾素含量最高,整个生育期高磷或不施磷都会影响钾素含量,只有适宜的施磷才能促进钾素含量达到最高峰.同一处理不同品种全株及各器官钾素含量在品种间没有明显的变化规律. 相似文献
25.
David M. Jaramillo José C. B. Dubeux Jr Joao M. B. Vendramini Luana M. D. Queiroz Erick R. S. Santos Martin Ruiz-Moreno Liza Garcia Daciele Sousa de Abreu Lucas Ramos de Miranda Michelle Cristina Fernando de Siqueira 《Grass and Forage Science》2020,75(2):153-158
Nitrogen fertilization is a common practice for sustaining forage production in forage systems in southeastern United States. Warm-season annual legumes may be an alternative forage to warm-season perennial grasses that do not require N fertilization. Sunn hemp (Crotalaria juncea L.) is a fast-growing, warm-season annual legume native to India and Pakistan. The objective of this 2-year study was to assess the herbage accumulation (HA), atmospheric N2 fixation (ANF) and nutritive value of sunn hemp. Treatments were the factorial arrangement of two sunn hemp cultivars (“Crescent Sun” and “Blue Leaf”), three seeding rates (17, 28 and 39 kg seed/ha) and seed inoculation (inoculated or non-inoculated seeds), distributed in a randomized complete block design with four replicates. Crescent sun had greater HA (3,218 vs. 1764 kg DM/ha) and ANF (41 vs. 25 kg N/ha). Blue leaf had greater crude protein (CP) (188 vs. 176 g/kg) and in vitro digestible organic matter (IVDOM) concentrations (564 vs. 531 g/kg) than crescent sun. Non-inoculated seed had greater CP than inoculated seed, 188 and 177 g/kg, respectively, and inoculation did not affect HA. Intermediate seeding rate (28 kg/ha) decreased HA (2002 kg DM/ha), while HA from high and low seeding rates (17 and 39 kg/ha, respectively) did not differ (2,863 and 2,615 kg DM/ha respectively). Planting non-inoculated crescent sun at 17 kg/ha seeding rate is a feasible management practice to produce sunn hemp in subtropical regions; however, inoculation should always be recommended for proper establishment. 相似文献
26.
Eui Jeong Han Hyun-Soo Kim Kalu Kapuge Asanka Sanjeewa Kyungsook Jung Youngheun Jee You-Jin Jeon Ilekuttige Priyan Shanura Fernando Ginnae Ahn 《Marine drugs》2020,18(12)
Sargassum horneri (S. horneri), an edible brown alga, has been proposed as a functional food with an improvement effect on abnormal skin immune responses. The present study investigates the anti-allergic effect of an ethanol extract from S. horneri (SHE) on immunoglobulin E (IgE)/bovine serum albumin (BSA)-mediated activation in bone marrow-derived cultured-mast cells (BMCMCs) and passive cutaneous anaphylaxis (PCA) reaction in mice. SHE markedly and dose-dependently suppressed the degranulation of BMCMCs by reducing the β-hexosaminidase and histamine release without cytotoxicity. In addition, SHE significantly decreased the FcεRI expression on the surface of BMCMCs and its IgE binding. Moreover, SHE reduced the mRNA expression and the production of allergic cytokines; interleukin (IL)-1β, IL-4, IL-5, IL-6, IL-10, IL-13; interferon (IFN)-γ and/or tumor necrosis factor (TNF)-α; and a chemokine, thymus and activation-regulated chemokine (TARC), by suppressing the activation of Src-family kinases and nuclear factor (NF)-κB signaling. In further study, the application of SHE reduced the PCA reaction in an IgE/BSA-induced type I allergic mice model. Taken together, we suggest that SHE has an anti-allergic effect in type I allergic responses. 相似文献
27.
28.
记述了裂脖跳小蜂属1新种--韩氏裂脖跳小蜂(Rhopus hanni Zu&Li, sp. nov.),1中国新记录种--硫磺裂脖跳小蜂(Rhopus sulphureus(Westwood,1837))。对新种及新记录种的形态特征和分布进行了详细的描述,并附有成虫特征照片。 相似文献
29.
以3个越橘品种‘奥尼尔’‘密斯梯’和‘北陆’为试验材料,比较光合生理特性和果实品质的差异。结果表明:越橘叶片为异面叶,角质层、上表皮和叶片厚度以‘密斯梯’最大,下表皮厚度以‘密斯梯’最小;‘密斯梯’光饱和点(LS,P)比‘奥尼尔’和‘北陆’高,补偿点(LC,P)比‘奥尼尔’和‘北陆’低,对光环境的适应性强;‘奥尼尔’和‘密斯梯’最大净光合速率(Pnmax)高于‘北陆’,光合潜力足;3个越橘品种单果质量由大到小依次为‘密斯梯’、‘奥尼尔’、‘北陆’;可溶性固形物和有机酸质量分数最高的是‘密斯梯’,维生素C质量分数最高的是‘奥尼尔’;单株产量由高到低依次为‘密斯梯’、‘奥尼尔’、‘北陆’。相关性分析表明:Pnmax与叶片厚度呈显著(P<0.05)正相关;LS,P与角质层厚度和上表皮厚度呈极显著(P<0.01)正相关;光合生理各项指标与果实品质存在一定的相关性。 相似文献
30.
Paola Marticorena Leonel Gonzalez Carlos Riquelme Fernando Silva Aciares 《Aquaculture Research》2020,51(9):3609-3622
The present study evaluated the effects of five bacterial isolates from the microalga Muriellopsis sp. on the microalgal biomass concentration (g/L), specific growth rate (K), photosynthetic quantum yield (QY), non‐photochemical quenching (NPQ), maximum relative electron transport rates (rETR max) and levels of nutritional components such as carbohydrates, lipids, proteins and carotenoids in Muriellopsis sp. cultivated in seawater under indoor and outdoor conditions. The bacterial strains were Microbacterium sp. Dom 1; Pseudomonas sp. Dom2; Microbacterium sp. Dom 3; Rhizobium sp. Dom 4; and Dietzia sp. Dom 5, as well as the Pseudoalteromonas sp. (SLP1), a bacterium known to promote the growth of microalgae. At the laboratory level, inoculation of the strains SLP1, Dom 1, Dom 3 and Dom 5 resulted in higher specific growth rates and biomass of the microalga. Subsequently, the best results were obtained with a combination of the selected bacterial strains (Dom1, Dom 3, Dom5 and SLP1) under outdoor culture conditions improved the biomass, proteins, carbohydrates and total carotenoids in 22.12%, 48.28%, 19,25% and 48.27%, respectively, compared to cultures without the incorporation of the selected bacteria (control), while no effects were observed on the photosynthetic parameters. Thus, it was demonstrated that positive associations of the selected bacterial strains played an important role in the production of Muriellopsis sp. acclimatized to grow in seawater. This is of crucial importance, especially in desert areas, where solar radiation is high and freshwater is a limited resource. 相似文献