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41.
42.
An analysis of structure of tree seedling populations on a Lahar 总被引:2,自引:0,他引:2
The structure of a tree seedling population is dependent on the interaction of several processes including seed dispersal, germination, survival, and competition on a physical landscape. Structural components (composition, size distributions, spatial distributions, age distributions, density, and history) of a tree seedling population on the Muddy River Lahar on the east side of Mount St. Helens were examined over a range of extents (1/10 m to 1000 m). Many of these component have rarely been examined at the larger extents listed here. Composition reflected distances to seed source and seed morphology. Seedling sizes are inversely proportional to depth to a buried soil if one existed. Spatial patterns indicated that seedling are clustered for tree seedlings less than 200 m apart, random for tree seedling from 200 m to 400 m and uniform for seedling greater than 400 m apart. This was confirmed by two measures of multidimensional spatial point pattern. Age distributions did not reflect the size distributions; old seedlings could be almost any size, young seedlings were constrained to be small in size. Densities appear to be typical for forests in the area. History of disturbance events (the lahar establishment, and successive ash, pumice, and erosion) has strongly influenced this tree seedling community. 相似文献
43.
通过柳杆扦插以及嫁接方法而快速繁育垂柳大苗的具体方法和技术措施,对缓减陕西省榆林地区当前市场垂柳大苗的供需矛盾具有比较重要的意义。 相似文献
44.
《Journal of Crop Improvement》2013,27(1):51-65
Abstract Only a few studies have been conducted in which regenerability of barley has been examined. In the current study, 17 barley genotypes (nine two-row malting type: Aster, Emon, Ruen, Jubiley, PV101, Körten, Krassi 2, Perun and Igri, and eight six-row feed types: Karnobat, Hemus, Jerun, Veslets, Aheloi 2, Diana, Panagon, and Izrgev) were evaluated for tissue-culture response from seedlings during a three-year period. Regenerable calli were obtained from all tested genotypes. Although there was much variation in regeneration capacity among the cultivars, plants were obtained from all cultivars. The majority of green plants grown to maturity were fertile and normal in appearance. The frequency of embryogénie callus induction and regenerability was influenced by genotype and growth conditions of the donor plants. Genotype was the most important determinant of the in vitro response. The best in vitro performance, based on ability to form regenerable calli and to regenerate plants was observed for Ruen, Aster, and Emon. 相似文献
45.
通过对落叶松播种苗根外追施钼酸铵液,促进苗高,地径生长,较明显地提高了苗木整体质量,对苗木木质化和提高苗木对不良环境的抵抗力有着积极的促进作用。 相似文献
46.
《Communications in Soil Science and Plant Analysis》2012,43(15-16):2059-2066
Abstract Plant growth promoting rhizobacteria (PGPR) (e.g., Azospirillum and Bacillus spp.) have been reported to enhance growth and fix N2 with several nonleguminous crops. These rhizobacteria have the potential to be applied to oil palm seedlings and, consequently, reduce the cost of nitrogenous fertilizer. The rhizobacteria are also known as a bioenhancer for the ability to increase root growth and enhanced water and nutrient absorption by the host plants. An experiment was carried out in the field nursery station, Federal Land Development Authorities (FELDA), Bukit Mendi, Pahang, Malaysia, to observe the effects of PGPR inoculation on enhanced nutrient accumulation and plant growth (tops and roots) of oil palm seedlings under field nursery conditions. The inoculation process showed positive response in enhancing higher accumulation of nitrogen (N), phosphorus (P), and potassium (K) in the plant tissues, enhanced root dry weight and top growth (dry matter and leaf chlorophyll content) of the host plants under field nursery conditions. 相似文献
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采用5种基质培育1年生湿地松容器苗,对不同基质培育的苗木地径、高度、鲜干重等指标进行了测定。结果表明,不同轻型基质配方对湿地松容器苗质量影响明显,表现较好的配方是Ⅳ号、Ⅱ号、Ⅲ号基质;同时,容器大小选择B型较好: 相似文献
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50.
微生物肥料促进红松幼苗生长的研究 总被引:2,自引:0,他引:2
微生物肥料采用多项国际国内领先技术研制、生产,具有高效、环保等特点。应用微生物肥料进行林业育苗可促进苗木的生长,为天然林保护工程和退耕还林还草工程提供高质量的幼苗。本文对微生物肥料培育林业建设苗木进行了研究,试验结果表明,微生物肥料促进红松生长,施用微生物肥料的红松,其株高、地径及生物量均有明显增长,可为林业建设提供优质苗木。 相似文献