饲料型四倍体刺槐组培扩繁技术

文章对饲料型四倍体刺槐组培快繁过程中的材料选择、培养条件以及生根与分化诸环节的关键技术进行了初步研究。通过对饲料型四倍体刺槐组培扩繁技术的初步试验,筛选出丛生芽诱导的培养基配方为：MS＋BA0.5＋NAA0.02;增殖培养阶段的最佳培养基配方为：MS＋BA0．2＋NAA0.05;诱导生根阶段的培养基为：1／2MS＋IBA0.3。筛选出来的培养基配方简单适用,经济有效．为四倍体刺槐良种扩繁和推广栽培提供了一条可行途径。     

四倍体刺槐组培瓶苗生根培养及生根苗移栽研究

四倍体刺槐是从韩国和匈牙利引进的大叶速生刺槐人工诱变的四倍体树种，具有速生、叶大、条粗、枝密、抗性强等特点，生长速度是普通刺槐的2倍以上。利用不同质量的组培瓶苗为材料，选取最佳生根状态的组培瓶苗进行生根培养和生根苗移栽试验，成功地筛选出生根培养基激素和生根苗移栽基质的最佳组合，建立了四倍体刺槐的再生系统。     

四倍体刺槐组培快繁技术研究

四倍体刺槐作为一种经济林木具有较高的应用价值，利用植物组培快繁技术可以显著提高四倍体刺槐的繁殖速度。通过试验，筛选出四倍体刺槐的增殖培养基配方：MS＋6－BA1.0mg/L NAA0.02mg/L和MS＋6－BA1.0mg/L IAA1.0mg/L。生根培养基配方：MS＋NAA0.01mg/L和不加任何激素的MS培养基。     

激素、通气和pH值对四倍体刺槐和二乔刺槐离体生长的影响

以四倍体刺槐和二乔刺槐的不定芽为试验材料,通过比较培养前后的芽伸长量、增殖率和生物量等指标,研究了激素、通气状况(封口材料)、培养基pH值对刺槐离体生长的影响.结果表明,在BA0.5mg/L、NAA0.1mg/L时,四倍体刺槐不定芽的生物量最大;在BA0.5mg/L、NAA0.5mg/L时,二乔刺槐不定芽的生物量最大.在湿度为35%±5%环境条件下,四倍体刺槐封口材料以耐高温塑料最好,二乔刺槐以棉塞最好;在湿度为55%±5%条件下,四倍体刺槐和二乔刺槐均以棉塞最好.在pH值为5.6、5.8和6.0时四倍体刺槐的增殖系数大,二乔刺槐在pH为6.4时的增殖系数大,而两品种在不同pH下的质量增量百分率差异不显著.     

Kan对四倍体刺槐愈伤组织及不定芽诱导的研究

以四倍体刺槐茎段为材料,接种于附加不同浓度卡那霉素(Kanamycin)的CNB培养基(含有一定浓度NAA、BA的MS培养基)上,当浓度达到50mg/L时,愈伤组织明显膨大、疏松,不定芽的诱导和生长几乎完全受到抑制,为筛选致死浓度;培养基中的激素种类和浓度对四倍体刺槐不定芽的诱导有明显影响,以CNB培养基培养10d后,转入附加50mg/L卡那霉素的DN培养基(含有一定浓度NAA、BA、ZT、2,4-D的MS培养基)上,通过两步诱导法,既提高了芽分化率(为94%),又达到了筛选的目的,此法为本研究的最佳方案。     

NAA和IBA对四倍体刺槐试管苗生根影响及不定根发育过程解剖观察

对四倍体刺槐无性系试管苗不定根的诱导进行了研究。采用 32 析因设计、二次回归正交设计的方法研究了在培养基中添加植物生长调节剂NAA和IBA对试管苗生根的影响 ,通过统计分析选出四倍体宽叶刺槐无性系的最适生根培养基是 1 2MS IBA 0 4mg·L- 1 NAA 0 2 5mg·L- 1 蔗糖 2 % 琼脂 0 6 % ;并对四倍体刺槐无性系试管苗不定根的发育过程进行了解剖观察 ,结果表明试管苗嫩梢无潜伏根原基 ,不定根由诱生根原基发育形成 ,诱生根原基源于髓射线细胞的分裂和分化。     

四倍体刺槐在林业工程中应用前景分析

四倍体刺槐是个新引进的优良的抗旱速生树种。本文介绍了四倍体刺槐的生物学特性、白银市发展四倍体刺槐的基本条件,探讨了四倍体刺槐在白银市的推广应用前景。     

四倍体刺槐的性状表现及繁殖技术

四倍体刺槐是从韩国引进的饲料树种 ,与普通刺槐相比 ,其叶密集、肥厚 ,有效成分含量高 ,呈小乔木状。该树种作为畜牧饲料树种栽培 ,具有很高的经济效益和社会效益。该树种为四倍体 ,仅引进部分单株 ,现在苗源紧缺 ,制约了饲料林发展速度 ,为防止性状分离 ,须采用无性繁殖。 5年来 ,我们对四倍体刺槐进行了微体快繁等技术研究 ,并对有关的性状进行了观察对比 ,对其有效成分进行了取样化验。现将四倍体刺槐的性状及繁殖技术介绍如下。1　四倍体刺槐的性状及饲料成分1.1　四倍体刺槐性状四倍体刺槐为小乔木 ,一回羽状复叶 ,树皮褐色、粗糙 ,叶…     

提高四倍体刺槐荒山造林成活率的试验

通过分析四倍体刺槐荒山造林成活率的试验,提出应用抗旱造林粉、壮苗深植、截干修枝等措施可明显提高四倍体刺槐荒山造林成活率。     

林芝地区引种四倍体刺槐叶片营养成分初报

对林芝地区引种的四倍体刺槐叶片营养成分进行分析研究,结果表明:(1)饲料型四倍体刺槐含水率比本地普通刺槐高2.45个百分点,全K比普通刺槐高0.0586个百分点,粗蛋白比普通刺槐高2.5488 个百分点;(2)饲料型四倍体刺槐叶片营养元素Ca、Mg、Cu、Fe、Zn的总量为0 4670mg/kg,而普通刺槐叶片营养元素总量为0.2072mg/kg,比普通刺槐的高0.2598mg/kg;(3)引种栽培四倍体刺槐除了Zn含量低于普通刺槐外,其他各项营养成分均高于普通刺槐,作为农牧区畜禽饲料,四倍体刺槐有较高的经济价值和社会效应。     

贫瘠丘陵地短轮伐期薪材树种生长过程的研究

尾叶桉、细叶桉、赤桉、粗皮桉、巨桉（简称桉树类，下同）和马占相思、粗果相思及薄果相思（简称相思类，下同）等８个树种，在水土严重流失的贫瘠丘陵地经７年的生长试验，结果表明：除巨桉和细叶桉在该立地生长较缓慢外，其余６个树种生长快，产量较高。尤其是尾叶桉和马占相思，７年生胸径年均生长量在１．０ｃｍ以上，单位面积生物量（地上部分鲜重，下同）为５２．６９ｔ／ｈｍ２和４３．６７ｔ／ｈｍ２。不同树种的生长比较：桉树类树种（除巨桉外）４年生以前胸径、树高和生物量生长均比相思类树种生长快，４年后相思类树种逐渐赶上或超过桉树类树种。性状生长高峰期分别为：胸径桉树类为２年生（细叶桉１年生）、相思类为３～４年生，树高桉树和相思类均为１年生，生物量桉树类为２～３年生、相思类为４～６年生。     

黑荆树丰产栽培技术研究

本文经过5年试验研究,从良种壮苗、立地分类、造林密度、林地管理、产量指标和经济效益估测,提出了黑荆丰产林栽培技术。所培育的丰产林,只要4年零2个月,其树高、胸径、产量可达到省标6年生立地指数级11和9的水平。     

Soil physical conditions and root growth in coconut plantations interplanted with nitrogen fixing trees in Sri Lanka

The study was carried out to investigate the possibility of improving degraded soil conditions of Andigama series by intercropping coconut (Cocos nucifera L.) with Calliandra calothyrsus, Leucaena leucocephala, Acacia auriculiformis and Gliricidia sepium. Bulk density was significantly low in NFT interplanted plots followed by improved aeration in AB and B horizons of the soil profile. Total and readily available water fraction was higher in AB and B horizons of calliandra, acacia and gliricidia interplanted plots over control plots due to the increase of organic matter content and root growth. Root growth and proliferation of calliandra in A horizon were predominantly higher than that of leucaena, acacia and gliricidia species. In contrast, gliricidia roots penetrated into B horizon more densely than roots of other species. Better root growth of coconut in A horizon was observed in acacia and calliandra plots than other plots. The total coconut root biomass in AB and B horizons was higher in gliricidia and acacia plots than other species, which accounted for 91% and 0.3% in AB horizon and 21% and 23% in B horizon for gliricidia and acacia, respectively compared to the control. Total root biomass of coconut in calliandra plots was reduced by 5%, and 45% in AB and B horizons respectively. Results indicated that soil physical conditions of Andigama series (gravelly soil) could be significantly improved by interplanting acacia and gliricidia, as indicated by enhanced coconut root growth and proliferation. This revised version was published online in August 2006 with corrections to the Cover Date.     

Growth of planted pine trees in response to variation in the densities of naturally regenerated acacias

This paper examines the hypothesis that in a pine plantation competition from naturally regenerated acacia trees can be controlled so that the benefits to the pine trees of nitrogen supply from the acacias could outweight their competing effects.Two herbicide experiments in Pinus radiata in eastern Victoria (Experiments A and B) and one in Pinus elliottii in south eastern Queensland (Experiment C) containing a range of densities of acacia stems and pine volume were used to test this hypothesis. In all three experiments no growth benefit to pine was found at any density of acacia stems. Hexazinone weedicide decreased acacia stems to the benefit of pine growth so that pine growth was negatively correlated with the density of acacia stems (Experiment A, r = ?0.801; Experiment B, r = ?0.712; Experiment C, r = ?0.913).Soil nitrogen concentrations examined in one experiment (A) increased in proportion to the number of acacia stems, but no growth response in P. radiata was found. A multiple correlation of acacia stems (x₁) and weedicide rates (x₂) explained 67% of the variance in soil nitrogen concentrations (y). If the increase in soil nitrogen is attributed to symbiotic N₂-fixation, the annual rate of N₂-fixation at a stocking of 4000 acacia stems per ha is 32 kg ha^?1.The hypothesis was not proven in as much as for the range of species and sites investigated, all denstities of naturally regenerated acacia stems adversely depressed pine volume growth.     

Chemical compounds released from five different woods used to make barrels for aging wines and spirits: volatile compounds and polyphenols

Aging wine and spirits in wooden barrels is an industrial process used to stabilize color and improve limpidity; many compounds are released from the wood and enrich the sensorial characteristics of the product. The main wood species used for making barrels is oak, but in particular cases also acacia, chestnut, cherry and mulberry. In this work, polyphenols contained in the extracts of these wood species obtained by solutions of 50% hydroalcohol as well as a model wine were studied and compared with the extracts from oak. The hydroalcoholic extracts of chestnut and mulberry had higher total polyphenols, followed by cherry, acacia and oak, respectively. The oak model wine extract had the highest percentage of polyphenols extractable by the wine, followed by chestnut, acacia, cherry and mulberry, respectively. Chestnut extracts had the highest percentage of oxidizable compounds, followed by acacia, oak, mulberry and cherry. The GC/MS–EI profile of 50% hydroalcoholic extracts revealed as principal volatiles several benzene compounds containing a guaiacol residue, and high contents of C₆–C₁₈ fatty acids. To our knowledge, this is the first study reporting on polyphenolic and complete volatile compounds characterization of these woods for oenological purposes.     

Analysis and Comparison on Anatomic Features and Properties of 4 Acacia Species

INTRODUCTION Acacia are widely distributed in tropical and subtropical regions in China. Because of certain climatic similarity in China and Australia, acacia were introduced from Australia since the 1960s as all purpose tree species which also play important roles in plantation forestry, soil and water conservation and landscaping (Fang Guigan et al. 1995). In recent years, more than 0.11 million ha of acacia palantations have been established in southern China, where some major specie…     

黑荆树组织培养繁殖技术的研究

通过黑荆树组织培养,探索基本培养基、生长调节物质、蔗糖含量、生长素种类和浓度不同对黑荆树嫩梢增殖、生根的影响。研究结果:采用春季培育42天的实生苗茎段作为外植体,在含有一定成分配比的培养基中,经7-20天,外植体长出1-3个芽梢。在低无机盐分的培养基中附加生长素NAA0.2-0.4mg/1,20-30天即可生根。研究指出:芽丛分化与细胞激动素,无机盐分含量,蔗糖浓度和生长素种类及浓度关系密切。     

Biomass production of tree fallows and their residual effect on maize in Zimbabwe

The rotation of maize (Zea mays) with fast-growing, N₂-fixing trees (improved fallows) can increase soil fertility and crop yields on N-deficient soils. There is little predictive understanding on the magnitude and duration of residual effects of improved fallows on maize yield. Our objectives were to determine the effect of fallow species and duration on biomass production and to relate biomass produced during the fallow to residual effects on maize. The study was conducted on an N-deficient, sandy loam (Alfisol) under unimodal rainfall conditions in Zimbabwe. Three fallow species — Acacia angustissima, pigeonpea (Cajanus cajan), and Sesbania sesban — of one-, two-, and three-year duration were followed by three seasons of maize. Pigeonpea and acacia produced more fallow biomass than sesbania. The regrowth of acacia during post-fallow maize cropping provided an annual input of biomass to maize. Grain yields for the first unfertilized maize crop after the fallows were higher following sesbania (mean = 4.2 Mg ha^–1) than acacia (mean = 2.6 Mg ha^–1). The increased yield of the first maize crop following sesbania was directly related to leaf biomass of sesbania at the end of the fallow. Nitrogen fertilizer did not increase yield of the first maize crop following one- and two-year sesbania fallows, but it increased yield following acacia fallows. Nitrogen fertilizer supplementation was not required for the first maize crop after sesbania, which produced high-quality biomass. For acacia, which produced low-quality biomass and regrew after cutting, N fertilizer increased yield of the first post-fallow maize crop, but it had little benefit on yield of the third post-fallow maize crop.This revised version was published online in November 2005 with corrections to the Cover Date.     

Differential behavior between acacia and Japanese larch woods in the formation and decomposition of hexenuronic acid during alkaline cooking

The effects of anthraquinone (AQ) and polysulfide (PS) on the hexenuronic acid (HexA) content of pulp during kraft cooking were studied using Acacia mearnsii (acacia) and Larix leptolepis (Japanese larch) sapwood. In contrast to the results of cooking Japanese larch at an H-factor of 1200, the HexA contents of acacia pulp with a kappa number of 20 at an H-factor of 291 did not differ greatly between the kraft, kraft-AQ, and PS-AQ cooking methods, although the hydroxide ion concentration in the acacia cooking liquor decreased on the addition of AQ or sulfur. To explain this difference, we studied the behavior of the formation and degradation of HexA during alkaline cooking of glucuronoxylan from cotton linter, which was cooked with 1.0 and 2.0 mol/l NaOH. The relationship between HexA content and H-factor during alkaline cooking of glucuronoxylan was clarified. The amount of HexA and its rate of decomposition were higher in the 2.0 mol/l solution than in the 1.0 mol/l solution. At a low H-factor similar to that for hardwood cooking, HexA content increased to a maximum level and then started to decrease at high hydroxide ion concentrations such as 2.0 mol/l, whereas it slowly decreased at low hydroxide concentrations such as 1.0 mol/l. At an H-factor of around 450, the HexA formation/degradation curve for 1.0 mol/l of hydroxide crossed the decomposition curve for 2.0 mol/l of hydroxide. Therefore, it was shown that at a low H-factor, a decrease in hydroxide ion concentration during acacia wood cooking had little effect on the HexA content of pulp.     

粤东发展相思木片基地的若干问题

基于相思类树种的生物学特性,及粤东地区具体的自然资源条件,在总结该类树各前期引种结果及现有良种储备的基础上,综合提出粤东发展相思丰产林的整体策略与具体措施,指出广东木片基地东移的效益及其潜在风险,为粤东发展相思人工林的科学管理与决策提供思参。