Adventitious rhizogenesis in Bambusa nutans and Bambusa tulda: Influence of seasonal variation, IBA and cutting type

The influence of seasonal variation, indole-3-butyric acid (IBA) and type of cuttings was examined on induction and growth of adventitious roots in Bambusa nutans Wall. and Bambusa tulda Roxb. Singlenode culm and culm-branch cuttings from the mature culms were provided with immersion treatment for 24 h of either water (control) or 2 mM IBA in four different seasons, i.e., spring (mid February), summer (mid May), rainy (mid July), and winter (mid November) and maintained for two months in the mist chamber at the relative humidity of (70±5)% and the temperature of (30±2)°C. In B. nutans, adventitious rooting occurred in both types of cuttings in all the seasons with the best rooting in the summer season i.e., May (88% in culm cuttings) and the least in winter. On the contrary, adventitious rooting was recorded only in culm cuttings in spring and summer season in B. tulda. IBA treatment significantly enhanced rooting, root number and root length; registering 14 to 17 times improvement over control in the best rooting season. Three factor-interactions (season × cutting type × IBA treatment) were significant for rooting in B. nutans and all characteristics, except sprouting in B. tulda. Thus, single-node culm and culm-branch cuttings in B. nutans and culm cuttings in B. tulda treated with 2 mM IBA during spring (February) to summer (May) season are recommended for their clonal multiplication.     

国外文献荟萃

印度东部刺竹人工林（Ⅱ）营养动态;黄金间碧玉枝扦插在扦插类型和生长激素影响下的生根能力;印度东北部阿萨姆邦卡恰区棕榈藤分布的土壤特征;用随机扩增多态性DNA（RAPD）分析斯里兰卡龙竹和奥克兰脱竹种群的遗传多样性及其关系;传统的方法生产竹炭的产量和质量比较;加纳龙头竹的遗传结构以及对采样和保存的影响……     

Standardization of harvesting age of bamboo shoots with respect to nutritional and anti-nutritional components

Bamboo shoots can be harvested at different ages but the data on the changes in nutritional composition with age are scanty. We standardized harvesting age of bamboo shoots in central India to obtain best quality produce with respect to nutritional composition. The shoots harvested on different days (2 20 days after emergence from ground) were analyzed for their nutritional (dietary fibres, carbohydrates, proteins, total phenols, ascorbic acid, sodium, potassium, phosphorus, calcium, magnesium and phenolic acids) and anti nutritional (cyanogen) constituents. A significant variation (at p≤0.5) was observed in the nutritional composition of shoots of Dendrocalamus asper, D. strictus and Bambusa tulda harvested at different days. An overall decrease was observed in proteins and total phenols while dietary fibres and carbohydrates increased with ages. Significant variation (at p≤0.5) was also observed in phenolic acids while minerals did not vary significantly. Results revealed that the optimum harvesting age for D. asper, D. strictus and B. tulda was on 10 14 days, 6 10 days and 10 16 days (after emergence from the ground) respectively. These results can be used to obtain quality bamboo shoots.     

An improvised in vitro vegetative propagation technique for <Emphasis Type="Italic">Bambusa tulda</Emphasis>: influence of season,sterilization and hormones

Season and concentration of sterilizing agents play a significant role for establishment of aseptic in vitro shoot cultures and sprouting of nodal explants from field growing culms of bamboo species. In the present investigation the nodal segment explants of Bambusa tulda Roxb collected in different seasons and treated with various concentrations of HgCl₂ showed significant variation in aseptic culture establishment and bud break. The rainy season (July–August) recorded with highest of 78% aseptic culture establishment whereas autumn recorded with lowest 46%. Summer and winter seasons emerged to be the best period, registering > 60% in vitro bud break. On the other hand, the autumn season had the lowest value for bud break, i.e. 42%. Among different doses of sterilizing agent tried, HgCl₂ 0.1% found to be suitable for maximum aseptic culture establishment (66%) as well as bud break (59%). However, among the interactions, summer season and the dose of 0.1% HgCl₂ exhibited maximum of 73% response for both aseptic culture establishment and bud break. MS medium (liquid) enriched with 5.0 µM BA + 5.0 µM Kn [Kinetin (N6-Furfuryladenine)] with additional supplementation of 100 µM glutamine + 0.1 µM IAA supported a maximum in vitro shoot multiplication of 4.75 fold. The proliferated shoots were successfully rooted on MS medium (liquid) supplemented 40 µM coumarin. The plantlets transferred to the polythene bags showed 98% survival.     

32种经济竹种的组培及苗木培育技术研究

选用了32个竹种作为微体快速繁殖材料,采用以芽繁芽的途径实现快繁。当选用竹子种子作为外植体时得到的组培效果最好,其次是幼年竹节芽和小枝芽,成年竹节芽最差。同等条件下,毛环刺竹、实心瓜多竹、孝顺竹、黄金碧玉竹、非洲锐药竹、麻竹和大佛肚竹更易成活和发笋,人面竹的成活率最低。选用蛭石作为育苗基质取得了较为理想的试验结果。用麻竹组培苗(1 a生苗)作为试验材料,得出腐殖土可作为优良的育苗基质,30%锯末+70%红土次之。组培苗移栽后施以NPK复合肥作为叶面肥,配以微量元素的追肥可提高成活率。对竹苗进行封顶处理可促进发笋。播种苗和组培苗便于运输,且成本低,但因竹子种子不易获得,所以组培苗是作为生产竹苗的最佳选择。     

丛生竹无性繁殖育苗试验研究

近两年来,对分布云南境内用途较广的近20个丛生竹种进行了多种方法的无性繁殖育苗试验,结果表明,采用节间切口埋秆法(包括带蔸和不带蔸)和竹苗分株育苗法,其育苗成活率可达70％以上;龙头竹、黄金间碧玉、佛肚竹、绵竹等,用枝条扦插法育苗也能获得较高的成活率;生长素类药剂对龙竹、慈竹、绵竹等竹种的次生枝以及黄金间碧玉、油勒竹、甜龙竹的主枝有促进生根的作用,生根率可比对照提高20％～40％。     

印度阿萨姆帮丘陵林地优势种竹子群聚开花情况:物候学、再生、对农村经济的影响以及保护

We recorded gregarious flowering of three bamboo species viz. Bambusa arundinacea, Bambusa tulda and Melocanna baccifera during rainy season from early March to late May, 2008 at lowland forest of Bajali area of Indo-Burma hotspot region. A regular method of field sampling of various forest types was used to map the bamboo species in Assam, India. Moreover, people’s perception on bamboo blooming was investigated at 17 sample plots covering 258 respondents inhabiting at the site at an average of 15 in each plots. A floral clump (inflorescence) emerged and developed into a giant panicle comprising of numerous florets. Two types of seeds viz. bacca and caryopsis were recorded in different species. Viviparous germination was noticed in few bacca seeds produced by M. baccifera and this has unusual occurrence in bamboo. Seed viability test shows that 75% caryopsis seeds were viable; these seeds had the potential of germination and can be used for mass regeneration. Most local respondents believe that bamboo flowering can result in population explosion of rodent, therefore, they think bamboo flowering is positively correlated with famine. This traditional belief results in massive destruction of bamboo clumps, which significantly impacts on rural economy.     

海南岛簕竹属5个竹种雨季光合特性与叶片形态结构性状

【目的】通过对簕竹属5个竹种雨季光合生理特性的研究,探究热带地区不同竹种雨季光合能力差异性,掌握不同竹种栽培特性,为竹种高效培育及园林应用提供理论依据。【方法】以海南岛簕竹属5个竹种作为研究材料,利用Li-6400便携式光合仪测定日变化、光响应曲线、CO2响应曲线,分析不同因子的影响及叶片形态结构性状与光合作用的相关性。【结果】1)不同竹种之间净光合速率存在较大差异,5个竹种净光合速率日变化规律呈现“双峰”曲线;2)各竹种光响应曲线在5—6月净光合速率较高,8—10月净光合速率较低,最大净光合速率(Pmax)、光饱和点(LSP)、暗呼吸速率(Rd)之间存在差异;青秆竹、粉单竹Pmax、LSP值高、Rd值低,光合能力较强;3)5个竹种CO2响应曲线均在5—8月净光合速率较高,9—10月净光合速率较低;相较于潜在最大净光合速率(Amax)、CO2饱和点(CSP),CO2补偿点(CCP)、光呼吸速率(Rp)、羧化速率(CE)之间存在差异;4)雨季中5个竹种Pn主要受气孔导度(Gs)、蒸腾速率(Tr)、气温(Ta)、光合有效辐射(PAR)、胞间CO2浓度(Ci)、大气CO2浓度(Ca)等因子制约;5个竹种叶片形态结构性状研究表明:佛肚竹、黄金间碧竹叶面积(LA)显著高于青秆竹、崖州竹、粉单竹(P<0.05),佛肚竹、青秆竹、黄金间碧竹叶厚度(LT)显著高于崖州竹、粉单竹(P<0.05),比叶面积(SLA)则相反;而5个竹种叶干物质含量(LDMC)差异不显著(F=0.691,P=0.615),不同竹种Pmax、Amax与LA、LT、LDMC、SLA相关性有所差异,与LA相关性较大。【结论】簕竹属5个竹种光合特征参数与叶片形态结构性状不同,竹种生理特性与叶片形态结构性状存在一定相关性。在竹类植物保存与利用中,叶面积可作为竹类植物筛选的主要性状指标。在园林配置中,青秆竹栽培区域较广、佛肚竹栽培区域较窄、崖州竹可在阴生条件下栽培、粉单竹适宜光照充足地区生长、黄金间碧竹介于青秆竹与崖州竹之间。     

Effects of clump spacing on nutrient distribution and root activity of <Emphasis Type="Italic">Dendrocalamus strictus</Emphasis> in the humid region of Kerala,peninsular India

The humid agroclimatic conditions of Kerala, India permit the cultivation of an array of bamboo species of which Dendrocalamus strictus Roxb. (Nees.) is an important one on account of its high growth rate and multiple uses. Stand density, a potential tool in controlling the productivity of woody ecosystems, its effect on growth and root distribution patterns may provide a better understanding of productivity optimization especially when bamboo-based intercropping options are considered. Growth attributes of 7-year-old bamboo (D. strictus) stands managed at variable spacing (4 × 4 m, 6 × 6 m, 8 × 8 m, 10 × 10 m, 12 × 12 m) were studied. Functional root activity among bamboo clumps were also studied using a radio tracer soil injection method in which the radio isotope ³²P was applied to soil at varying depths and lateral distances from the clump. Results indicate that spacing exerts a profound influence on growth of bamboo. Widely spaced bamboo exhibited higher clump diameters and crown widths while clump heights were better under closer spacing. Clump height was 30% lower and DBH 52% higher at the widest spacing (12 × 12 m) compared to the closest spacing (4 × 4 m). With increasing soil depth and lateral distance, root activity decreased significantly. Root activity near the clump base was highest (809 counts per minute, cpm; 50 cm depth and 50 cm lateral distance) at 4 × 4 m. Tracer study further showed wider distribution of root activity with increase in clump spacing. It may be concluded that the intensive foraging zone of bamboo is within a 50-cm radius around the clump irrespective of spacing. N, P and K content in the upper 20 cm was 2197, 21, and 203 kg/ha respectively for the closely spaced bamboo (4 × 4 m) which were significantly higher than corresponding nutrient content at wider spacings. About 50% of N, P and K were present within the 0–20 cm soil layer, which decreased drastically beyond the 20 cm depth. The results suggest that stand management practices through planting density regulation can modify the resource acquisition patterns of D. strictus which in turn can change growth and productivity considerably. Such information on root activities, spatial and temporal strategies of resource sharing will be helpful in deciding the effective nutrition zone for D. strictus. Further, the study throws light on the spatial distribution of non-competitive zones for productivity optimization yields, especially when intercropping practices are considered.     

丛生竹类假植延时栽培技术试验

竹苗栽植通常在春季进行,但若遇春季干旱则会影响栽植成活率。本文试验研究了竹苗假植延时栽培技术,即将竹苗在春季萌芽前先行假植,待夏季雨季来临时,再进行定植,这样可避开春季干旱。试验结果显示,将竹苗进行假植延时栽培,造林成活率可达95%以上,竹苗的适宜栽培时间可延长约4个月,从而有效规避干旱季节,节约管护成本,提高造林成活率。该技术在造林和园林绿化中有较大的应用价值。     

凤尾竹埋节繁殖技术研究

试验研究了不同生长调节剂浓度、不同基质配方、不同埋节方式、不同埋节季节对凤尾竹埋节生根的影响。结果表明：凤尾竹节段繁殖最佳选择是在春季采用双节段平埋,节段用200 mg/kg浓度的ABT 1号生根粉浸泡2 h,基质采用珍珠岩+蛭石+沙土+营养土（1∶1∶1∶1）,插穗生根率可达50.00%。     

Seasonal dependence of rooting success in cuttings from natural forest trees in Madagascar

Four ligneous species from the tropical forest in the east of Madagascar, with a proven or potentially high economic value, were subject to ‘low-tech’ vegetative propagation tests from stem cuttings. The species concerned were Aphloia theiformis, Ilex mitis, Prunus africana and Ravensara aromatica. The cuttings were three-node segments of stems on which one leaf was retained. All the species proved amenable to rooting. The maximum percentage of rooting ranged from 33% for P. africana to 60% for I. mitis. Rooting success was dependant on the season of cutting (high in the hot season, from October to May, and null in cold season). This study is the first successful attempt at propagating cuttings from Malagasy forest species. This result is of particular importance to P. africana, threatened by destructive exploitation in Madagascar. It goes a step further in the domestication of this species by demonstrating the ability of cutting from 10 year old ortets collected in natural forest to root as it offers the possibility of a reliable and effective method of reintroduction for the species in overexploited zones.     

龙竹无性繁殖育苗技术

龙竹具有生长快、周期短、径级大、产量高、材质好、用途广等特点,是云南省发展竹产业的优良竹种。基于多年的实践经验,总结了龙竹的埋节、埋秆无性繁殖育苗的关键技术,以期为芒市的龙竹生产提供指导。     

Reclamation of roads and landings with balsam poplar cuttings

Balsam poplar (Populus balsamifera L.) can easily be grown when planted as dormant, unrooted cuttings. The first part of this research project consisted of a greenhouse study to identify the best combination of pre-planting treatments to maximize rooting of hardwood cuttings for large-scale greenhouse propagation. Eighty-four treatment combinations were tested on 10 cm-long cuttings, including seven soaking lengths of time (0, 1, 2, 3, 4, 5 and 14 days), three dips (none, powder and liquid rooting hormone), two collection dates (fall and spring), and two cutting selections (average trees and a superior clone).Secondly, we tested the performance of unrooted cuttings on typical forestry sites lacking natural regeneration, using 30 cm-long cuttings and full-length whips (>60 cm). Three pre-planting treatment combinations were used (soaking for 1 or 3 days, or 3 days with a dip in rooting hormone). Other factors tested were two collection dates (fall and spring), two cutting selections (average trees and a superior clone), two storage methods (stored as full whips or cut to size), and two cutting locations (basal or top 30 cm of stools).     

Propagation ofRobinia pseudoacacia Linn. and Grewiaoptiva Drummond from rooted stem cuttings

Rapid vegetative propagation of promising multipurpose trees is an important need in agroforestry development. Grewia optiva andRobinia pseudoacacia are two such species, about the propagation of which very little is known. The rooting ability of stem cuttings harvested from juvenile (2 year-old) and mature hardwood(15 year-old) trees of Robinia pseudoacacia andGrewia optiva was significantly influenced by the period or season of harvesting cutting. Juvenile cuttings of both species rooted significantly better (42.9% in R. pseudoacacia and 46.6% in G. optiva) than mature hardwood cuttings (34.7% in R.pseudoacacia and 41.4% in G. optiva). The effect was more pronounced in auxin treated cuttings. InR. pseudoacacia, the highest rooting in juvenile(83.3%) and mature (66.6%) cuttings prepared in spring season was observed with the NAA (500 mg/l) treatment. InG. optiva, IBA (250 mg/l) in the monsoon season was most effective and recorded a maximum of 80% and 70%rooting in juvenile and mature cuttings, respectively. The auxin treatments also significantly enhanced the number of roots (23.8 inR. pseudoacacia and 17.6 in G.optiva) and their mean length (14.3 cm inR. pseudoacacia and 16.1 cm inG. optiva). Interactions between age, season and treatments were significant at P < 0.05 level for rooting percent in R. pseudoacacia and non-significant for G. optiva. The results of this study suggest that it is possible to develop clones of genetically superior trees of R. pseudoacacia and G.optiva for use in agroforestry or afforestation programmes. This revised version was published online in June 2006 with corrections to the Cover Date.     

花绿竹生物经济特性及与传统绿竹的比较

花绿竹是近年选育的浙南夏秋笋新品种。与当地传统主栽种绿竹相比,有以下特点:(1)秆色为花色,绿底黄条,传统主栽种绿竹竹秆为绿色。(2)物候上抽枝发叶早,当年生新竹于高生长停止后即萌芽抽枝,抽枝率达80%;而传统种绿竹当年抽发枝叶相对较少。(3)习性上分枝低,多数竹株只要光线合适,即从地上部分第2～3节就开始抽枝,节间长度为两头小,中间长,11～32cm不等。(4)成竹高3～7m,胸径2.7～4.4cm。高生长期历时45～70天,夜生长量大于日生长量。径生长历时14天。高生长满足三次曲线方程:y=0.000 09x3+0.014 6x2+1.238 1x(R2=0.989 1)。(5)在浙南地区,花绿竹在海拔300 m以下、最低气温-5℃以上均可生长并形成经济产量。出笋初期6月初,末期10月中旬,7—8月为盛期,出笋量占总量的83%以上。(6)丰产早产性能好(3～4年生竹丛,产量在5.25～6.00 t/hm2,较对照种高25%),笋体品质优(糖分含量高、出土笋苦味轻)、质地脆、口感佳。花绿竹可作为笋用竹推广应用,也可考虑兼作笋用、观赏竹开发。     

Crop productivity under differently lopped canopies of multipurpose trees in Central Himalaya, India

Ficus species are multipurpose trees well known by rural populations in Sahelian and Sudanian zones of Africa. Their uses are well documented but their amenability for vegetative propagation has not been extensively studied. This paper compares the rooting ability of stem and aerial root cuttings from thirteen Ficus species found in West Africa. It highlights the differences between species belonging to the sub-genera Sycomorus and Urostigma. The former show no capacity to propagate from cuttings whereas the latter, with epiphytic development, can be propagated by cuttings, although this capacity varies among species. Thus, F. thonningii, F. leprieurii and F. ovata are easily propagated, while F. platyphylla and F. elasticoides are propagated with difficulty. The rooting capacity also varies depending on the cutting material used. It decreases in the following order: long leafless hardwood cuttings (pole) > nodal cuttings > apical cuttings. Rooting potential increases when the cuttings are harvested towards the end of the dry season(March to May). Aerial root can be used for cuttings in all species of the sub-genus Urostigma. The capacity of root cuttings to regenerate is greatest when cuttings are collected at the beginning of the dry season (November). In this case, wound-induced adventitious roots arise at the basal end of the cutting while de novo buds are developed from the cambium at the distal end. The subsequent morphological development is identical to that of a stem cutting. These results clarify and allow the optimal use of the knowledge and methods developed by the indigenous people of the Sahel and could assist and promote fig tree (Ficus sp.) domestication in the dry tropics.This revised version was published online in November 2005 with corrections to the Cover Date.