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对组培技术应用的几点建议 总被引：4，自引：1，他引：4
通过多年从事植物组织培养实践，根据植物组培技术特点，认为植物组织培养应当在植物脱毒、提高育种水平及加速育种进程等方面推广应用，而对于一些木本植物组培，应慎重行事。 相似文献
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植物组织培养研究进展与应用概况 总被引：18，自引：5，他引：18
介绍了国内外植物组织培养技术应用的概况,并详细阐述了该技术的国内外的研究进展,主要包括污染、褐变、玻璃化原因、机理与防治对策的研究,培养条件的研究,外植体选择的研究及利用组织培养技术进行植物物种基因改造或转基因的研究。提出了解决影响植物组培苗发展的障碍因素,全力推进组培苗的产业化;扩展植物组培次生代谢产物生产范围与规模。加强生物制品的研制与开发;加强植物组培方式与培养水平的研究,探索新的培养途径等建议。为从事植物组织培养研究与生产应用的科技工作者提供了参考与借鉴。 相似文献
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从外植体选择及分化途径、影响增殖、生根的主要因素三方面,概述了近年来林木植物组培的研究进展,外植体3种分化途径(腋芽萌发途径、间接器官发生途径、体细胞发生途径)有其相应的最适外植体类型,林木组培首选腋芽萌发途径。培养基和植物生长调节剂是影响增殖的两大因素,对培养基的探索已从对林木植物组培常用培养基的筛选发展到无糖培养基的探索,出现了光自养、开放组培等概念;植物生长调节剂是生根的关键因素,外源激素与内源激素的相互作用对增殖有较大影响。阐述了组培中褐化、玻璃化、污染三大难题的起因和解决措施,对褐化和玻璃化的研究主要集中在外植体的生理状态和培养环境方面,提出无糖组培通过对培养环境进行改善,有望改善褐化、玻璃化问题;传统组培希望从无菌技术层面解决污染难题,这也造成了组培成本偏高的问题,进而对开放组培和无糖组培的探索,通过抑菌剂的添加及糖的剔除有望降低组培对无菌操作的要求。随着组培技术的发展,在抑菌剂加入的条件下,不进行高温高压灭菌,进行开放式的组培;利用植物自生的光合能力,剔除培养基中的蔗糖,同时改变光照条件、培养环境中的CO_2浓度、湿度,以促进外植体光自养微繁殖生长;二者均着眼于降低组培成本,简化组培程序,有望使组培技术得到革新。本文对林木组织培养研究进展进行综述,为今后开展林木植物组织培养技术的研究提供重要参考。 相似文献
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植物无糖组培技术研究进展 总被引：5，自引：0，他引：5
利用试管苗小植株的光合自养能力可以对其进行无糖培养.这种组织培养模式可以有效地防止污染并能显著地促进试管苗的生长,尤其是增强试管苗的生根能力.植物无糖组培在环境调节、培养基质以及培养容器等方面较传统的组织培养有很大改善.综述了近20 a来在植物试管苗的无糖组培技术的研究进展,并对无糖组培的前景作了展望. 相似文献
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本文针对组织培养技术的发展概况,包括新方法的采用,新观点的提出,并从七个方面进行了综述：影响组织培养的因素;培养基种类及常用培养基配方;外植体材料的选择;培养方式的研究及发展;应用组培法快繁观叶植物的途径;花卉组织培养的应用价值;稀土元素在组织培养上的应用研究。 相似文献
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植物无糖组织培养技术是自20世纪60年代常规组培技术在生产中逐渐得到广泛应用以来，于近年出现的一项革新性的突破技术。综述了国内外无糖组织培养技术的发展利用状况，并以常规组织培养技术作比较，阐述了此项革新技术的发展前景。 相似文献
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木本植物组织培养技术在林业科研与生产中的应用与局限 总被引：15，自引：1，他引：15
针对近年来全国各地植物组培研究机构的相继诞生和组培产业投资热潮,从木本植物组培技术特点、产业化现状、存在的问题及解决的方法等方面,浅析木本植物组织培养技术在科研与生产中的应用前景与局限,为广大科技工作者更好地发展我国试管快繁技术和商业应用领域的研究,客观正确预测木本植物组培技术在林业生产中推广应用的效益及避免盲目投资风险提供参考。 相似文献
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预防和控制污染是植物组织培养苗工厂化生产中重要的技术环节。文章从蓝莓苗组培的污染原因、类型及防治方法分析了怎样减少组织培养中出现的污染问题,从而达到降低生产成本、减少对植株造成的伤害、减少接种源污染的几率等目的。 相似文献
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我国杉木组织培养技术研究进展 总被引：3，自引：1，他引：2
杉木是我国南方特有的速生用材树种,具有生长快、产量高、材质好和用途广的特点,在南方林业生产中占据重要地位。熟悉和掌握杉木的组织培养技术,对促进杉木产业的发展具有重要意义。文中从叶、茎尖、茎段和离体胚等外植体的选择,外植体消毒,愈伤组织和芽的诱导分化,继代增殖培养以及壮苗与生根等方面简述近几年我国杉木组织培养技术的研究进展,对杉木组培快繁中的灭菌技术、培养基筛选和生长调节物质使用水平等技术环节进行评述,同时提出目前研究中存在的几个主要问题和今后的发展方向。 相似文献
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Because of their high growth rate and tolerance to bare soil, two exotic Acacia species, Acacia auriculiformis and Acacia mangium, have been commonly planted in degraded areas of South China. With their large canopies and ability to fix nitrogen, the two Acacia species have also been considered to act as nurse plants for understory plants. The current study clarified the nursing effects of the Acacia species by comparing microclimate characteristics and physiological traits of native plant seedlings at three sites: under the canopies of the each Acacia species and on bare land (open site). Although the sites were not replicated, the results indicated that adult trees of both Acacia species can facilitate native species, but that A. mangium has greater facilitating effects due to greater temperature buffering, radiation reduction, and nutrient amelioration. In response to facilitation, three species (Castanopsis hystrix, Michelia macclurei, and Manglietia glauca) with different shade-tolerant traits growing under Acacia canopies expressed distinct adaptations. For the three species, the chlorophyll fluorescence curves of rETR and ΔF/Fm′ were higher under A. auriculiformis and on the open site than under A. mangium. The maximum quantum yield in PSII(Fv/Fm) in diurnal changes of the three species showed that all the Fv/Fm values were between 0.70 and 0.84 and that the Fv/Fm values were mostly higher under A. mangium than on the open site or under A. auriculiformis. Total chlorophyll content and both chlorophyll a and b contents in the three species were higher under the Acacia species than on the open site, while chlorophyll a/b ratio was higher on the open site. In contrast, the carotenoid content in C. hystrix and M. macclurei was lower under the two Acacia species than on the open site, while the opposite was true for M. glauca. The results demonstrate that the adaptation of the understory species to abiotic environmental factors is not restricted to a single mechanism but apparently involves a group of interrelated, adaptive suites. And also these adaptations were species-specific and especially related to their shade tolerance. 相似文献
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We examined water use by maturing Eucalyptus regnans, growing with or without an mid-storey stratum of Acacia spp. (Acacia dealbata or A. melanoxylon), for >180 consecutive days. Study sites were located in the Upper Yarra catchment area in south-eastern Australia. Depending on their contribution to stand basal area, mid-storey Acacia spp. increased total stand water use by up to 30%. Monthly water use in such stands reached more than 640,000 L ha−1 (compared to 545,000 L ha−1 in stands where acacias were absent) in early spring. Water use was curvilinearly related to sapwood area of Acacia spp. and logistically related to sapwood area of E. regnans. Water use of all three species showed a strong relation to daily maximum air temperatures. Distinct and simple relationships provide clear guides to the likely impacts of climate change and forest management on water yield. We compared a traditional up-scaling approach, from individual tree water use to stand water use, to a new approach that incorporates variation in temperature. Development of this approach can lead to greater precision of stand water use estimates – and in turn catchment water yield – under current climate change scenarios, which predict a rise in air temperatures of 0.6–2.5 °C by 2050 for the study area. Our temperature-dependent approach suggests that under conditions of non-limiting water availability, stand water use will rise by 2% for every 0.25 °C increase in maximum air temperatures during winter, and possibly more than that during summer. 相似文献
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South African coastal dune forests are young, highly disturbed subtropical communities where conventional models of forest dynamics may be challenged. We tested predictions from the gap-phase regeneration model by comparing seedlings of three common species representing contrasting regeneration strategies: Acacia karroo as a ruderal, Celtis africana as a coloniser of forest gaps, and Diospyros natalensis as a late-successional species. We grew seedlings under contrasting light and nitrogen levels in a greenhouse and in the field for 1 year to compare their growth and survival rates, allocation and photosynthetic traits. Species’ growth rates generally followed the expected order: Acacia > Celtis > Diospyros, but Acacia responded strongly to light and Celtis responded strongly to nitrogen, leading to cross-overs in growth rates. The plasticity of allocation and photosynthesis did not clearly differentiate the strategies, although it was greater in the light-demanding species. Acacia and Celtis tended to survive better in Acacia stands than in forest plots. Leaf-level light compensation points (LCPs) were similar for the three species in most conditions, but auxiliary data suggest Diospyros has a lower whole-plant LCP than Acacia. Growth rates and LCPs were lower than most of those reported for primary-forest species in the literature, suggesting an unusual degree of shade-tolerance in this habitat. We discuss reasons why variation in shade-tolerance may be less important here than in the prevailing model for forest regeneration and suggest other biotic factors that may help differentiate regeneration niches. 相似文献
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Acacia plantation establishment might cause soil acidification in strongly weathered soils in the wet tropics because the base cations in the soil are translocated rapidly to plant biomass during Acacia growth. We examined whether soils under an Acacia plantation were acidified, as well as the factors causing soil acidification. We compared soils from 10 stands of 8-year-old Acacia mangium plantations with soils from 10 secondary forests and eight Imperata cylindrica grasslands, which were transformed into Acacia plantations. Soil samples were collected every 5–30 cm in depth, and pH and related soil properties were analyzed. Soil pH was significantly lower in Acacia plantations and secondary forests than in Imperata grasslands at every soil depth. The difference was about 1.0 pH unit at 0–5 cm and 0.5 pH unit at 25–30 cm. A significant positive correlation between pH and base saturation at 0–20 cm depth indicated that the low pH under forest vegetation was associated with exchangeable cation status. Using analysis of covariance (ANCOVA), with clay content as the covariate, exchangeable Ca (Ex-Ca) and Mg (Ex-Mg) stocks were significantly lower in forested areas than in Imperata grasslands at any clay content which was strongly related to exchangeable cation stock. The adjusted average Ex-Ca stock calculated by ANCOVA was 249 kg ha−1 in Acacia plantations, 200 kg ha−1 in secondary forests, and 756 kg ha−1 in Imperata grasslands at 0–30 cm. Based on a comparison of estimated nutrient stocks in biomass and soil among the vegetation types, the translocation of base cations from soil to plant biomass might cause a decrease in exchangeable cations and soil acidification in Acacia plantations. 相似文献
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Quang-Vuong Le Kushan Udayanga Tennakoon Faizah Metali 《Journal of Sustainable Forestry》2019,38(3):230-243
Seedlings of invasive species often exhibit superior physiological traits that facilitate their spread at early stages of invasion, although it is unclear whether these traits persist at the post-establishment stage. To determine whether mature exotic Acacia spp. possess superior traits over mature native plants, we compared foliar gas exchange and chlorophyll a fluorescence of Acacia auriculiformis and Acacia mangium coexisting with tropical heath forest tree species Buchanania arborescens and Dillenia suffruticosa in Brunei Darussalam. The CO2 assimilation rates of Acacia spp. were significantly higher than those of heath species at current prevailing conditions of ~400 ppm ambient CO2, 1,500 µmol m?2 s?1 photosynthetically active radiation and 30°C leaf temperature. The photosystem II of Acacia spp. exhibited significantly higher maximum quantum yield of primary photochemistry at comparable temperatures, and was more sensitive to an elevated temperature (42°C for 1 h). Better photosynthetic performance of Acacia spp., due to larger stomatal openings, better light harvesting efficiency, and greater plasticity in photosystem II, may enable adult Acacia trees to sustain a competitive growth advantage and suppress native tropical heath forest species. The competitive advantage maintained by Acacia spp. in post-establishment stage likely facilitates the establishment of monospecific Acacia stands in invaded heath forests. 相似文献
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Andrés Fuentes-Ramírez Aníbal Pauchard Lohengrin A. Cavieres Rafael A. García 《Forest Ecology and Management》2011,261(6):1003-1009
Tree invasions cause important conservation problems, such as changes in plant community composition, reduced regeneration rates of native species, and alteration in landscape structures. One of the most invasive tree genera in the world is Acacia (Fabaceae). In Chile, Acacia dealbata Link is distributed in the mediterranean zone, mostly associated with roadsides and anthropogenic disturbances. In this paper we address the following questions: How does A. dealbata perform across a gradient of native forest and invasive stands? Will it be capable of establishing itself in non-invaded native forests and regenerating under its own canopy in the absence of disturbances? From a contrasting viewpoint, will native species such as Cryptocarya alba (Molina) Looser and Nothofagus obliqua (Mirb.) Oerst be able to survive in an A. dealbata stand, allowing re-colonization of the invaded area? We conducted survival and growth experiments on A. dealbata seedlings in three sites near Concepción, Chile (36°S-72°W) under three conditions: under Acacia stand, in a close native forest and on an intermediate matrix between these two conditions. We compared this to the performance of two native trees (Cryptocarya alba and Nothofagus obliqua). Results showed that A. dealbata and C. alba have high growth and establishment capacities within the native forest, but on the intermediate matrix only A. dealbata can grow and survive. C. alba survives at significantly higher rates than A. dealbata within Acacia stand. Nothofagus obliqua only survive at a very low rate in the native forest. Without disturbances, A. dealbata would be successful on the intermediate matrix and within native forest, while C. alba seems capable of surviving and establishing itself in invaded areas, thereby contributing to recovery and restoration of natural spaces. The interplay between Acacia dealbata and the native vegetation may show us a larger picture of how invasive species are capable of expanding even into forested ecosystems and, furthermore, how we can restore native vegetation and avoid further invasion. 相似文献
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通过ITS-rpl16序列和mat K序列的分子分析,对中国现有金合欢属的各亚属间的亲缘关系进行了研究,结果表明:我国现有广义金合欢属的14个种大致被聚为相思亚属、皮刺亚属和金合欢亚属3大类,原产中国的3种皮刺亚属的种聚成1支,表明印度金合欢和羽叶金合欢关系更近,二者再与儿茶形成姐妹类群。基于选自美洲、非洲、澳大利亚和中国乡土种(印度金合欢、羽叶金合欢和儿茶)共40个金合欢属种和1个外类群的mat K序列建立的系统发育树表明:皮刺亚属和相思亚属的亲缘性关系比与金合欢亚属的亲缘关系更近,相思亚属和金合欢亚属均是单系类群,而皮刺亚属属于并系类群;中国的几个乡土种都与非洲一些种的亲缘关系较近,聚为1支。 相似文献
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Cattle (Bos taurus) are the largest exotic ungulates introduced in Patagonian forest, and the most widely distributed. Although detrimental effects of cattle grazing on these forests have been documented, cattle-plant interaction has never been studied from the perspective of the feeding ecology of this ungulate. We assessed cattle diet on a seasonal basis by microhistological analysis of fecal samples in Los Alerces National Reserve, Argentina. We found that: (1) the annual diet was largely dominated by graminoids and shrubs; (2) the percentage of shrubs, forbs, and other species in the diet changed significantly across seasons; (3) cattle predominantly fed on Nothofagus spp., Berberis spp., Maytenus spp., Chusquea culeou, and Hierocloe sp.; and (4) selected more forbs than other vegetation types in warm-growing season, while highly selected graminoids and avoided shrubs during the cold-dormant season. Although these general selection patterns of plant types were observed seasonally, selection or avoidance at the species level was also recorded. Cattle have been described as grazers, suggesting that the composition of their diet should be dominated by graminoids. However, we found that cattle include significant proportions of woody plants in their diet. These results offer the first data available on diet composition and selection in a protected area in Patagonian forests, a first step towards understanding detrimental effects of cattle grazing on native forest from the perspective of their feeding ecology. Our evidence that cattle positively select Nothofagus spp. and Austrocedrus chilensis suggests that they can negatively affect the establishment and growth of these species. Given that livestock ranching is an important form of subsistence for economically disadvantaged settlers of Los Alerces National Reserve, alternatives to current ranching activities must be considered to improve their livelihood and reduce the negative effects of cattle on forests. 相似文献