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香蕉是重要的热带亚热带水果,本文综合相关文献资料,从香蕉的起源与分布和现代生物技术在香蕉种质资源的研究与应用等剖析香蕉种质资源研究和应用的现状。对香蕉起源与分布的认识是香蕉种质资源研究的基础,目前多数学者都承认香蕉起源东南亚,对演化路线却存在许多争议,现代分子生物技术为解决这一问题提供了机会;分子标记技术成为香蕉遗传多样性研究的重要工具,可以很方便地进行香蕉分类、亲缘关系及演化做较为精确的研究,甚至辅助育种的应用;组织培养、细胞悬浮体系和原生质体培养技术的不断成熟,促进香蕉种质创新的发展,使香蕉突变育种和转基因育种成为可能。 相似文献
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<正> 本报告提出了死覆盖对种植椰子和香蕉的湿热带砖红壤温度影响的分析结果。椰子园和香蕉园有或无死覆盖,其10cm深土层的土壤温度明显不同。有死覆盖的,椰子园5—10cm土层土温降低2—6℃,香蕉园降低1—6℃。有死覆盖的椰子园和香蕉园,土表温度每阡在30—33℃之间变化,而没有死覆盖的椰子园土表温度可高达 相似文献
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Intercropping of immature rubber in Sri Lanka: present status and financial analysis of intercrops planted at three densities of banana 总被引：2，自引：0，他引：2
V. H. L. Rodrigo C. M. Stirling R. M. A. K. B. Naranpanawa P. H. M. U. Herath 《Agroforestry Systems》2001,51(1):35-48
Intercropping during the unproductive immature stage of rubber provides one means of addressing the gap in income suffered by smallholders after replanting or new planting of rubber. A survey of smallholder rubber plantations was undertaken to determine the current status of intercropping in Sri Lanka. A total of 587 smallholders were included in the survey that encompassed the four major rubber growing regions; Kalutura, Kegalle, Colombo and Rathnapura. Intercropping was practised on relatively few farms, with the percentage of smallholders engaged in intercropping ranging from 23 to 54%. Banana was the most common companion crop of rubber with a current extension recommendation for a single row of banana planted between rubber rows. A financial appraisal, based on data from an agronomic experiment, revealed the potential to raise profits by more than 350% if planting density of banana was increased threefold over current recommendations. Profitability of banana intercrops was governed by four major components; yield expected in the third year, fertiliser costs, labour costs and market value of banana fruit. The influence of planting density of banana on each component is discussed. The survey indicated that most farmers grew banana without chemical fertiliser. If high density banana intercropping is to be widely adopted as a means of raising income on immature rubber lands, then current recommendations for chemical inputs need to be addressed in order to bring initial costs down to a sustainable level for smallholders.This revised version was published online in November 2005 with corrections to the Cover Date. 相似文献
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R. Petra Wollboldt Gerhard Zuckerstätter Hedda K. Weber Per Tomas Larsson Herbert Sixta 《Wood Science and Technology》2010,44(4):533-546
The correlation of structural assembly on a molecular level with macroscale properties such as accessibility and reactivity
was investigated. A series of TCF-bleached E. globulus kraft dissolving pulps was prepared aiming at a specification suitable for viscose application. The removal of xylan to a
comparable level was achieved by different pre- and post-treatments. Solid-state CP-MAS 13C NMR was used to determine the degree of order and the lateral fibril dimensions of cellulose fibrils. The results of the
NMR measurements were related to the processability of these pulps during viscose manufacture, expressed in terms of filterability
of the viscose dope and its amount of undissolved particles. The cellulose crystallinity did not affect the pulp reactivity.
It was noticed that the cold caustic extracted (CCE) pulps revealed both large fibril aggregate width as determined from NMR
data and low reactivity toward xanthation at the same time. These pulps exhibited significantly higher amounts of alkali-resistant
xylan than those prepared by prehydrolysis kraft cooking. 相似文献
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霍山石斛组培丛生芽诱导增殖及生根技术 总被引：1，自引：0，他引：1
以霍山石斛无根试管苗为试材,研究了丛生芽诱导增殖和生根技术.丛生芽诱导增殖通过4因素3水平正交试验,筛选出的最适培养基为1/2MS 0.2 mg/LKT 0.2 mg/L NAA 0.3 mg/L 6-BA.4个因子对霍山石斛丛生芽诱导的影响顺序依次为:KT＞基本培养基＞6-BA＞NAA,其中,KT对霍山石斛丛生芽的诱导效果极为显著.添加不同浓度的生长素及香蕉泥进行生根诱导,其生根效果排序为:香蕉泥＞IBA＞NAA,最佳的生根培养基是MS基本培养基添加20%香蕉泥,生根率可达94.3%. 相似文献
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The steam explosion (SE) pretreatment associated with the organosolv process was investigated to produce dissolving pulp from eucalyptus. Prehydrolysis Kraft (PHK) pulping was also done to produce viscose and acetate grade pulps as reference. The organosolv pulps were delignified in two steps with sodium chlorite. Viscose and acetate grade PHK pulps were bleached by OD0(EH)D1P and OD0(EP)D1PCCE sequences, respectively. Dilute acid-catalyzed (with acid addition) SE pretreatment dissolved more xylan than auto-catalyzed (no acid addition) SE pretreatment. Steam-exploded unbleached organosolv pulps showed lower residual lignin content and screened yield than unbleached organosolv pulps without SE pretreatment. Steam explosion pretreatment helped to decrease lignin content and damaged fiber length of unbleached organosolv pulps. The 1.0% H2SO4 organosolv pulp (organosolv dissolving pulp at bioconversion conditions) showed the highest reactivity. Even showing low viscosity for some applications, in general, the organosolv dissolving pulps produced in this study can be used for making lyocell fibers. 相似文献
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Rodrigo Favreto Ricardo Silva Pereira Mello Luís Rios de Moura Baptista 《Agroforestry Systems》2010,80(2):303-313
The palm Euterpe edulis has high ecological and economic importance in Brazil. Currently, this species is being cultivated and managed for spontaneous
regeneration in banana plantations. However, there are no data comparing its plantation growth performance to its native forest
growth. We evaluated growth and mortality (M) of individuals of E. edulis planted in secondary dense ombrophilous forest and in banana plantations, as well as their relationships with site variables
(canopy opening, soil nutrient availability, density of existing E. edulis, and herbivory). Twelve banana plantation sites and 12 sites in secondary dense ombrophilous forests were selected. At each
site, 25 young individuals of E. edulis were planted in 2003. Annually until 2008, morphometric, herbivory, and M of the individuals were evaluated. In 2008, canopy
and soil variables were measured at each plot. E. edulis growth was five times higher in banana plots compared to forest plots; current annual increment on height reached 38.9 cm
in banana plots, compared to 7.3 cm in forest plots. M was relatively low and similar at both sites, presenting an intraspecific
density-dependence pattern. Significant correlations were found between morphometric variables, M, and herbivory of E. edulis and canopy and soil variables. Euterpe edulis presented plasticity that allows for its establishment in banana plantations, indicating high potential for management in
agroforestry consortia. Such management may be a useful conservation strategy for this and other shade-tolerant species. 相似文献
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In view of the low pasture productivity in the Central American humid tropics where cattle rearing is a major land-use activity, it is important to examine the potential of alternate feed sources for ruminant feeding. Erythrina berteroana Uban, locally known as poro, and green banana (Musa AAA) fruits have been identified as two such potential sources. The effects of feeding poro as a grazing supplement and diet supplementation with green banana fruits on cattle productivity were evaluated in a long-term trial in Costa Rica. Daily liveweight (LW) gains were measured and samples of all feed material were analyzed for crude protein and in vitro dry matter (DM) digestibility. Pasture availability was high, averaging 0.17 t DM ha day–1 over the grazing period. The main grass species were Paspalum fasciculatium Poiret, Axonopus compressus Swartz and to a lesser extent African star grass (Cynodon nlemfluensis Vanderyst). DM yields of poro declined significantly with time (> 50%) when it was managed with a two-month resting period but remained higher when subsequently managed with a three-month resting period. Average daily LW gain of animals was 21% to 26% higher with two hours daily browsing of poro than for animals only grazing pasture. Highest liveweight gain was achieved when diets were supplemented with banana and there was no additional benefit when poro was fed in addition to banana. This suggests that fodder banks of poro or supplements with green banana can improve cattle nutrition in the humid tropics.This revised version was published online in November 2005 with corrections to the Cover Date. 相似文献