In vitro clonal propagation of mature Tectona grandis through axillary bud proliferation

An in vitro clonal propagation procedure for mature Tectona grandis (teak) trees is described. Multiple shoots were induced from nodal segments through axillary bud proliferation. A shoot multiplication rate of 6.33 was achieved on Murashige and Skoog's (MS) medium supplemented with 10 μM 6-benzyladenine BA and 1 μM 1-naphthalene acetic acid (NAA) during every subculture cycle of 4 weeks. In vitro raised shoots could be successfully rooted (66.66%) on liquid MS medium supplemented with 15 μM NAA, with 1.60 roots per shoot, every 6 weeks of culture. In vitro hardening was carried out in sand soaked with half-strength MS medium (organic free). The plantlets were acclimatized first in a mist chamber and then in polybags in a mixture of soil, sand, and farmyard manure (1 : 1 : 1 v/v) in a shade house.     

Variation in Shoot Anatomy and Rooting Behaviour of Stem Cuttings in Relation to Age of Donor Plants in Teak (Tectona grandis Linn. f.)

Shoot anatomical features viz., number of vessel elements, width and length of vessel and fibre elements were studied in relation to juvenility/maturity of teak (Tectona grandis Linn. f.). The findings show significant differences in these features, which indicates that variation in shoot anatomy can be used as a reliable indicator of juvenility/maturity in teak. The effect of age of donor plants and application of auxins on adventitious root formation in single noded leafy stem cuttings of teak was also investigated. Aging of donor trees suppressed rooting and sprouting of cuttings, but increased callus formation at the base of cuttings. Per cent rooting and per cent sprouting in cuttings decreased as age of donor plants increased from 2-months to 15-years and up to 30-years. IBA treatment promoted per cent rooting as well as per cent sprouting, NAA promoted only rooting and it suppressed sprouting. The effect of auxin treatment on rooting and sprouting of teak stem cuttings varied with the age of donor plants. Auxin and its concentration, which suppressed rooting and sprouting in cuttings of younger donor plants, actually promoted rooting when cuttings were taken from more mature donor plants. It appears that the auxin requirement for causing and promoting rooting in teak cuttings increased with increasing age of donor plants. The higher auxin requirement for causing and promoting rooting in cuttings of older trees may be due to a decrease in the content on endogenous auxins or decreased sensitivity of aging tissues to rooting promoters and /or accumulation of inhibitory substances which inhibit rooting.     

An efficient method for clonal propagation and in vitro establishment of softwood shoots from epicormic buds of teak (Tectona grandis L.)

Softwood shoots were produced from 40 cm long stem segments placed horizontally in flat trays containing sterilized sand under natural light or shade conditions for subsequent rooting and micropropagation studies in teak (Tectona grandis L.). Higher number of shoots (6.17) per log was produced under natural light as compared to shade conditions. Forcing was also better in natural light as compared to shade in terms of shoot length, number of nodes or leaves. For rooting, 2–4 cm long softwood shoots were excised and treated with either indole-3-butyric acid (IBA) or α-naphthyl acetic acid (NAA) at 0, 1000, 2000 or 3000 μmol·L^–1 each or with combinations (1000 + 1000, 2000 + 2000 or 3000 + 3000 μmol·L^–1) and then placed in flat trays containing autoclaved sand at 25 ± 2ºC in 16 h photoperiod at 35 µmol·m^–2·s^–1. After 28 days, softwood cuttings treated with IBA + NAA (3000 + 3000 μmol·L–1) had highest rooting percentage (89.3%) with 5.5 mean roots. Shoot apex and nodal explants of softwood cuttings were pretreated with 0.1% (w/v) ascorbic acid, boric acid, activated charcoal, citric acid, glutamine or polyvinylpolypyrollidone (PVP) for 24 h to remove phenolic compounds before surface disinfestation. Glutamine (Gl) and PVP were equally effective resulting in 60% establishment of shoot apices on MS medium supplemented with 10 μmol·L–1 6-benzylaminopurine (BAP) + 5 μmol·L–1 NAA. Using shoot apices, highest (42.80) number of multiple shoots with 54.33 mm shoot length were obtained on MS + BAP (8.8 μmol·L–1) + IBA (2 μmol·L–1) after 45 days. Shoots were successfully rooted and acclimatized to greenhouse     

柚木菌根及其对苗期生长影响的研究

在广东、广西、云南 7个点进行采样调查的结果表明 ,在自然条件下 ,7个柚木根系样品全部感染AM菌 ,感染率达 4 0 %　 70 % ,感染指数达 11 6 7　 19 17;4个AM菌对 12个不同地理种源柚木苗人工接种的结果表明 ,全部处理均形成感染 ,感染率达 70 %　 10 0 % ;利用 3个AM菌对 4个柚木无性系进行人工接种 ,感染率达 86 %　 10 0 % ,感染指数达 2 8 33　 5 2 5 0 ;接种株苗高比对照增加 5 4 0 %　4 0 8% ,地径增加 5 %　 4 30 % ,生物量增加 116 4 %　 2 5 74 8% ;统计结果表明 ,无论无性系、菌种或无性系×菌种在苗木高、地径及生物量上与对照的差异均为极显著 ;综合比较 ,3个菌种对柚木生长均有接种效果 ,以G90 0 4效果最好 ,G6 0 0 8菌株次之 ,再次是G30 0 6菌株     

柚木苗木分级标准的探讨

对贵州省册亨县阳光公司培育的1年生柚木播种苗进行随机抽样调查,在调查苗木生长及根系性状基础上,采用x±S方法对各样方苗木性状进行苗木等级检验,结果表明I级苗的苗高大于38.21 cm,地径大于0.72 cm;Ⅱ级苗的苗高范围在27.59 cm~38.21 cm,地径的范围在0.63 cm~0.72 cm;Ⅲ级苗的苗高小于27.59 cm,地径小于0.63 cm。     

柚木引种栽培技术探讨

阐述了珍贵树种柚木的主要引种栽培技术。为我省生产上大面积推广柚木栽培提供了理论依据和技术指导。     

雷州半岛柚木生长早期表现

2002年、2003年在湛江市林业科学研究所开始进行柚木种植试验。至2009年,试验结果表明,柚木在雷州半岛生长表现较好,7年生最大单株胸径23.5 cm,平均15.68 cm。平均树高12.89 m,生长均优于做对照的黎蒴栲、火力楠和橄榄,生长比较排列是柚木>黎蒴栲>橄榄>火力楠。但是柚木耐风害和低温能力均不如其它三种树种。试验结果表明在雷州半岛选择背风向阳的立地种植柚木是有前途的,低温和台风是限制柚木发展的主要因子。     

Diversity and genetic structure of teak (<Emphasis Type="Italic">Tectona grandis</Emphasis> L.f) in its natural range using DNA microsatellite markers

Teak (Tectona grandis L.f.) is considered to be an extraordinarily durable building timber with a worldwide reputation. Its widespread use has entailed the over-exploitation of natural forests and a large reduction in natural diversity. Fifteen microsatellite markers were used to study the genetic variability and structure of 166 teak trees distributed over the whole natural area of teak. Analysis showed that in the teak natural area there were four main centers of genetic variability. Two clusters were in India and could be considered as main centers of genetic diversity in teak. The third cluster mainly consisting of populations in Thailand and Laos was genetically very distinct from the Indian populations but presented only half as much allelic variability. A fourth cluster from Central Laos showed even less genetic variability. The use of SSR markers for conservation of teak forest diversity is discussed.     

柚木丰产栽培技术研究进展

柚木被誉为林中之王,用途很多,几乎很难找到其他树种代替。它是世界上人们渴求的珍贵木材树种之一,所以柚木人工繁殖和丰产栽培显得尤为重要。本文总结了柚木生物生态学特性、主要价值、人工繁殖和丰产栽培技术方面的研究现状,并对柚木今后的研究工作进行了探讨。     

柚木次生木质部导管分子观察研究

运用细胞图象分析系统及显微照相的方法对柚木次生木质部导管分子进行了观察研究.在柚木的次生木质部导管分子中存在着许多不同的样式,分别对其进行了描述,并从导管分子个体发育与系统发育的角度进行了讨论.     

柚木苗期多因素施肥试验

以N、P、K、Mg、Z(Zeolite沸石)为苗期施肥因素,采用L8(41×24)正交设计,P为4个水平,其余2个水平,不施肥作对照,共9个处理,研究不同施肥处理对柚木苗生长和干物质质量的影响。方差分析结果表明:不同施肥处理间7个月生柚木的生长及干物质质量差异极显著,处理5(P1Z2N1K1Mg2)的生长指标和各项干物质质量指标是8个施肥处理中最好的,与其余的施肥处理呈显著或极显著差异。与对照相比,7个月生的柚木苗高、地径、总干物质质量、根干物质质量、茎干物质质量和叶干物质质量分别是对照的3.58、2.74、11.78、11.29、10.24、17.79、8.15倍。沸石促进了柚木苗生长和各项干物质质量的形成,添加沸石的7个月生的柚木苗高、地径、总干物质质量、根干物质质量、茎干物质质量和叶干物质质量分别是不添加沸石的2.10、1.69、4.02、3.17、2.94、2.60倍。不同P水平间的苗木生长和干物质质量的差异也极显著,低P水平对柚木苗生长和干物质质量的影响要优于高P水平,容器苗培育P肥最佳施肥量为基质质量的0.7%。添加Mg也对柚木苗生长和干物质质量的形成起促进作用。     

柚木分子生物学研究进展与建议

柚木是世界名贵的用材树种之一,分子生物学技术的应用在较大程度上促进了柚木遗传育种的研究与发展.文章总结归纳了柚木分子生物学研究进展,包括同功酶、分子标记和转基因等技术方面的研究,内容涉及遗传变异与遗传多样性、种源地理来源鉴定、优树选择与无性系鉴定、分子标记辅助选择育种、抗虫转基因育种和基因克隆,同时分析探讨了当前我国柚木遗传育种研究存在的问题,并针对性地提出了我国柚木分子生物学研究的几点建议,以期对柚木该领域的深入研究起到积极的促进作用.     

柚木(Tectona grandis)无性系繁育及造林技术

柚木为马鞭草科柚木属植物,是世界上最珍贵的用材树种之一。文章介绍了柚木的生物学特性、无性繁殖即组培技术要点以及造林技术,论述了柚木在我省的推广前景。     

柚木茎段组培快繁技术

以柚木（Tectona grandis）3年生优良无性系植株茎段为外植体,研究柚木组织培养快速繁殖技术.结果显示,用0.1％的HgCl2浸泡外植体4 min,无菌水清洗2次后,再用0.1％的HgCl2浸泡4 min的消毒效果最好,无菌活外植体得率30％左右;适宜茎段离体培养的基本培养基为MS;最佳的增殖培养基为MS ＋6-BA 1.0mg/L,芽增殖系数6.1以上;单芽在1/2 MS＋ NAA 1.0 mg/L＋IBA 0.5 mg/L培养基上的生根率达到90％以上,每株能长3～4条根,平均根长1.5～2.5 cm,根系健壮.     

元江县干热河谷引种柚木生长情况初探

在1965年引种自缅甸的元江县干热河谷柚木林分中设置4个调查样地,对在不同小地形、不同坡向和不同土壤质地上的样木生长情况进行了研究.结果表明:位于山坡的林分生长差,位于山凹的林分生长最好;在半阴坡上的样木生长状况明显优于半阳坡,同坡向相比,水土条件好的地方树木生长优于水土条件差的地方.     

柚木嫩枝扦插

对柚木组培苗田间扦插扩繁的主要技术开展了研究.结果表明:不同无性系的萌条数量有显著差异,高的达14.8 条/月,低的5.5 条/月,平均9.1 条/月;从0.05～2.00 mg/L,随着IBA浓度的提高,生根率、根条数、总根长等生根指标均呈现有规律的变化;综合考虑各种生根指标,以IBA0.05 mg/L为最佳生根激素处理;扦插介质对柚木插穗生根有显著的影响,以泥炭土 黄心土按1∶1混合为最佳扦插介质;不同无性系的扦插成活率不同,从56.7%至90.0%,变动幅度大;随扦插季节变化,生根率和成活率均呈现有规律的变化,5～6月份的生根率中等,7～8月最高,9～10月份迅速下降,成活率随季节的变化也是两头低、中间高,6～8月的成活率最高,大于93%;综合考虑生根率、成活率和苗木生长期,5～8月份为柚木适宜的嫩枝扦插季节.     

河口县立地条件对柚木生长影响的调查研究

选择河口县马场等3个造林地块，从海拔100-800m共设置标准地20块、样方20块，调查不同立地条件对柚木生长的影响。结果为海拔400m以下为柚木最适宜区，400-600m为适宜区，600-800m为次适宜区；坡脚好于坡腹，坡腹好于坡顶；背风山坳、坡麓、沟谷、平地优于迎风坡及坡顶；土壤厚度大于80cm则柚木生长良好，低于50cm则生长不良；以马鹿草为主的植被群落有利于柚木生长，而以白茅为主的植被群落对柚木生长极为不利。     

播种时间和处理方法对柚木种子萌发的影响

于2013年3—6月,每月分别采用石灰浆、赤霉素、清水处理柚木种子,进行播种时间和处理方法两因素交叉分组试验,结果表明,4—5月是柚木最佳播种时间;柚木种子不经过处理直接播种发芽率比较高,其他处理都不能提高发芽率;在3月播种,浸泡清水3 d后再用赤霉素50 mg·L-1浸泡20 h能显著加快种子萌发速度;3月和4月播种,采用赤霉素50~200 mg·L-1处理种子能显著促进苗高生长,当赤霉素质量浓度达到200 mg·L-1时将显著抑制叶宽生长。     

贵州省柚木适生区域研究

采用设置样地的方法对贵州省引种的柚木进行生长情况的调查分析.结果表明,贵州省引种柚木的适生区域是南部的南、北盘江低热河谷地区,红水河、南盘江岸边海拔700 m以下以及北盘江两岸海拔550 m以下地区.在适生区域发展柚木采用四旁植树的方法效果最佳,坡地造林宜选择土层厚度80 cm以上的地域,采取反斜坡带状整地效果较好.     

柚木截杆苗培育技术研究

通过持续15年对柚木进行试验育苗及大量生产性育苗,结果表明:种子催芽处理是柚木育苗成败的关键,催芽效果:综合处理法日晒夜浸法石灰浆浸沤法对照;苗木速生期在5~10月,苗木生长量占全年总生长量的73.3%;育苗节令选择4月最佳;幼苗分床以1~2对真叶移植为宜;全苗鲜重最能代表苗木的质量,现场操作的量化指标以苗木平均地径为主;D2.5 cm为Ⅰ级苗,D=1.5~2.5 cm为Ⅱ级苗,D1.5cm为Ⅲ级苗。