The use of isozyme genetic markers to estimate the rate of outcrossing in a Sitka spruce (Picea sitchensis (Bong.) Carr.) seed orchard in Scotland

Effects of genotype, collection date, auxin treatment, crown position and artificial chilling on rooting and subsequent vegetative growth of Cupressus sempervirens L. softwood cuttings taken from 13-year-old plants were evaluated. Three different clones (318, 296 and 22) previously selected for resistance to cypress cortical cancer caused by Seiridium cardinale were used. In all these clones, both the IBA treated and the untreated cuttings showed seasonal periodicity of rooting. Untreated cuttings rooted best when collected in April (up to 49% for the best clone, i.e. 296) and rooted very poorly in July and October. Auxin treatments appeared unable to overcome this periodicity, as the cuttings taken in July and October did not respond to IBA stimulation. However, in January and April, IBA treatments enhanced adventitious root formation of poorly rooting clones (318 and 22), as well as of clone 296, which performed best (89%) when cuttings were treated in April with 1.5% IBA. Cuttings of each clone collected in the lower third of the crown of the donor trees showed a significantly higher rooting percentage, when compared with those from the upper third. A 4-week post-severance chilling treatment (4°C) significantly enhanced the rooting capacity of cuttings taken in January, while a longer chilling treatment (8 weeks) had a negative effect. The subsequent growth of the rooted cuttings was not affected by either the crown position of the severed cuttings, or the genotype.     

Effect of Genotype,Age and Treatment of Stock Plants on Propagation of Hybrid Aspen (Populus tremula×Populus tremuloides) by Root Cuttings

The ability of 1- and 2-yr-old stock plants of five hybrid aspen (Populus tremula L.×Populus tremuloides Michx.) clones to produce root cuttings and sprout was studied. Different stock plant treatments designed to improve root mass production and rooting vigour of cuttings were also tested. The 2-yr-old stock plants produced significantly more cuttings than the 1-yr-olds, but the age of stock plants did not have a significant impact on the sprouting ability of cuttings. The stock plant treatments caused significant variation in sprouting of cuttings. The clones differed significantly in their ability to produce cuttings and to sprout, and in the time needed for sprouting. Variations in the studied characteristics indicate that genotype selection will be efficient and economically worthwhile in root cutting method. The root cutting method clearly results in more cuttings and sprouted aspen plants per stock plant than the stem cutting method.     

Mini-cuttings: an effective technique for the propagation of <Emphasis Type="Italic">Pinus pinaster</Emphasis> Ait.

Pinus pinaster Ait. is one of the main forest tree species planted in Spain, Portugal and France. Due to its high economic relevance, there is considerable interest in developing techniques for vegetative breeding aimed at mass propagation. In this study we present a mini-propagation protocol in order to define an efficient method to propagate families or clones of P. pinaster. We carried out three experiments using mini-cuttings of 3–5 cm in length with the aim of evaluating the effects of temperature (4°C vs. 25°C), plant growth regulator (IBA) and shoot age on rooting ability. Percentage of rooted cuttings and morphological root variables were recorded. The percentage of rooted cuttings per treatment ranged from 68 to 97%. Treatment with IBA significantly influenced the rooting process at 25°C but not at 4°C. The number of apexes, length, area and volume of roots were all positively affected by temperature treatment. Shoot age also had a positive effect on rooting capacity of cuttings, with the cuttings from the youngest shoots (70 days after pruning) having higher rooting percentages, ranging from 84.7 to 98.3%. The use of juvenile material, good environmental conditions and IBA all benefited the rooting of clonal material, resulting in high rooting capacity. This study presents an innovative propagation protocol for P. pinaster that can be used as a tool in breeding programs.     

不同穗条类型、长度的欧洲云杉扦插苗质量评价

[目的]为欧洲云杉扦插穗条选择和扦插苗培育提供依据。[方法]采用完全随机区组试验设计,研究了2种穗条类型(嫩枝基部带1.5年生硬枝、嫩枝)、3种穗条长度(5 10、10 15、15 20 cm)的嫩枝扦插苗从移植当年到第3年的成活率、保存率和生长情况。[结果]2种穗条类型扦插苗间的移植成活率和保存率差异不显著,但移植后嫩枝基部带1.5年生硬枝扦插苗的苗高、新梢生长量、地径、侧枝数、冠幅、鲜质量、干质量差异显著,都是嫩枝基部带1.5年生硬枝扦插苗大于嫩枝扦插苗。3种长度扦插苗的移植成活率、保存率的差异均显著;其中,15 20 cm长度穗条扦插苗移植成活率和保存率最高,分别是98.00%和86.00%,不同长度穗条扦插苗移植成苗率逐年下降,而且与穗条长度有关,弱小穗条获得的扦插苗成苗率低;5 10 cm的扦插苗移植成活率为46.00%,到第3年时保存率仅为23.33%,且移植后苗高、新梢生长量、地径、侧枝数、冠幅、鲜质量、干质量的差异也显著,且都以15 20cm穗条的扦插苗值最高,10 15 cm穗条的扦插苗次之,5 10 cm的扦插苗最小。嫩枝带硬枝扦插苗的苗木质量指数(QI)是嫩枝的7.74倍,15 20 cm穗条的扦插苗质量指数(QI)是5 10、10 15 cm扦插苗的5.47、5.23倍。扦插苗地径初始值与移植当年地径、苗高初始值与移植当年苗高间呈极显著正相关关系。[结论]扦插苗最初的生根状况和穗条质量影响后期培育过程中的存活和生长,嫩枝基部带1.5年生硬枝扦插苗和15 20 cm穗条的扦插苗不仅移植成活率、保存率高,而且生长量、生物量、质量指数都比短而弱小穗条的扦插苗高。     

Rooting and early shoot characteristics of Picea abies (L.) karst. cuttings originating from shoots with enforced vertical growth

Picea abies mother‐plants from 10 serially propagated clones (14 years old, chronologically) were treated in four different ways: (1) control with intact, non‐manipulated plants; (2) like (1) but with the leader cut off; (3) intact plants but with all branches of the upper two whorls forced to grow in a vertical way; and (4) like (3) but with the leader cut off. Cuttings from four positions (cutting‐types) on the mother‐plants were collected, rooted and evaluated for rooting %, number of main roots, number of lateral roots, plagiotrophy, needle symmetry on leader and growth of leader. Treatments 3 and 4 resulted in cuttings with more plagiotropic growth but with better rooting, more lateral roots and better growth than did cuttings from treatments 1 and 2. The genotype had a significant influence on rooting. Number of main roots was significantly influenced by the genotype and the cutting‐type, but not of the mother‐plant treatment. Symmetry of needles on the leader was fairly weakly influenced by genotype and cutting‐type yet not influenced by mother‐plant treatment. Clone effect was significant for leader growth.     

Rejuvenation of juvenile growth characters in picea abies

Cuttings were made from six‐year‐old seedlings of Picea abies L. (Karst.) that had been studied in the Stockholm phytotron. The seedlings belonged to four full‐sib families, one being of French origin, one of North‐Swedish origin and two being hybrids between parents of North‐Swedish and French origin. Nine clones from each family were included. After the rooting phase, the cuttings were exposed to the same cultivation regimes as the seedling ortets. Characteristics of growth rhythm, percentage free growth and leader length were recorded during the 2nd to the 5th growth period (GP). Plagiotropic growth habit was recorded in the 3rd to the 5th growth period, and, characteristics of the rooting phase were studied. A juvenile behaviour very similar to that characterizing growth periods 2–3 of the seedlings was observed for growth rhythm characteristics and for free growth capacity during GP2 of the cuttings. The absolute value of the differences between each observation of the seedling ortets in GP6 and the means of the cuttings in GP2 produced a new variable that quantified the degree of rejuvenation. This new variable was meaningfully calculated only for growth rhythm and growth pattern variables. A gradual reversion of the growth rhythm occurred for the cuttings, which corresponded to the change with increasing age for the seedlings. The capacity for free growth, on the contrary, disappeared already in GP3 for the cuttings, except for the French family. A large variation in the rejuvenation ability between families was observed. Furthermore, the rejuvenation ability was negatively correlated with the ability to grow plagiotropically.     

A comparison of pre-planting treatments on hardwood cuttings of four hybrid poplar clones

Rooting and early growth of four hybrid poplar clones (Populus spp.) planted in a greenhouse were examined after applying 40 pre-rooting treatment combinations to dormant cuttings. Treatments included 2 cutting lengths (5 and 10 cm), 5 soaking times (0, 2, 4, 8, and 12 days), and 4 dips (chitosan, rooting hormone powder, liquid rooting hormone added to the soaking water, and none). Significant differences in both rooting percentages and growth were shown between clones after 7 weeks of growth. Ten cm cuttings had 29% greater rooting success, 28% more above-ground growth, and 12% lower root/shoot ratios than 5 cm cuttings. Cuttings planted without soaking had the lowest rooting success, at less than 45% on average. Commercial rooting hormones decreased the number of rooted cuttings but increased root/shoot ratios. For optimal rooting, we recommend using 10 cm cuttings, soaked for 2 days in water (4 days for the Jackii10 clone) without any additional dipping/hormone substance.     

Norway spruce emblings as cutting donors for tree breeding and production

In the Nordic countries, Norway spruce (Picea abies) is a major species in tree breeding. In order to facilitate breeding work and availability of highly bred forest regeneration material, the time required for breeding and implementation of results should be shortened. This could be done by accelerating production of clonal material for field testing, and possibly for planting stock, by combining production of rooted cuttings with somatic embryogenesis (SE). This would allow efficient production of numerous plants of the same genotype, with equal age and propagation history between genotypes. In the present work, we studied the rooting potential of cuttings from Norway spruce emblings. Altogether 36 clones from 12 families representing elite breeding materials and ornamental forms were examined under different rooting conditions (container type and rooting media) in 2015 and 2016. Our results show that Norway spruce emblings are good donors for cuttings. Best combination (peat–vermiculite mixture and Plantek 81f containers) resulted in 91% rooting, variation among the tested clones of elite breeding materials being 55–100% per treatment. The rooting variation between families is acceptable for breeding purposes. High rooting (87–96%) of ornamental forms indicates propagation potential with the combination of SE and rooted cuttings.     

Rooting response of late summer cuttings taken from Pinus sylvestris half-sib families

Abstract

One-year-old Pinus sylvestris donor plants were top-pruned in early May, allowing cuttings of three types to develop: shoots from adventitious buds near the top of the plant (T), weaker shoots from adventitious buds emerging further down the stem (M) and shoots from normal buds on branches (B). Cuttings from 46 half-sib families were collected at the beginning of August, treated with indole-butyric acid, immediately inserted in containers with porous substrate and put in a greenhouse, where soil was heated and high air humidity was maintained. The rooting frequency, estimated by counting living plants 10 months after insertion, was 54%. The family variance component for rooting was small and non-significant, while the clone-within-family component was strongly significant and accounted for 21% of the total random variance. Type M and type B cuttings showed significantly better rooting ability than type T cuttings. Including only plants with at least four acceptable shoots in the propagation experiment, 61% of the potential donor plants remained, without loss of any family. If a more restricted selection criterion was applied, including only plants with at least eight acceptable shoots, 21% remained, with a loss of 13 families. It was concluded that rooting ability of P. sylvestris can be brought to a level that could justify its inclusion in a breeding programme. The lack of family variation was also favourable in this respect, as no families were lost owing to low rooting response. However, the number of suitable cuttings produced by the donor plants needs to be increased.     

Parameters affecting shoot production and rooting of cuttings from lodgepole pine hedges

By propagating lodgepole pine (Pinus contorta) cuttings in vivo, we obtained after 7 growing cycles (ca 3.5 years) in a greenhouse, sufficient number of cuttings from most families to establish clonal progeny tests. Twenty-one full-sib families with approximately 20 clones per family were studied for five years. Years when cuttings were set, families within latitude and clones within families differed significantly in rooting percentages, with the variance components 4.2%, 8.2% and 9.5%, respectively. One way to get a frequent and uniform rooting is to take cuttings from non-leading shoots since they have higher rooting percentage than leading shoots. Neither total length of the cuttings nor length of the primary needles were significantly correlated to rooting percentage. With appropriate management of the ortets and the cuttings during rooting, most clones could be included in a cutting propagation program.     

Vegetative propagation of <Emphasis Type="Italic">Litsea monopetala</Emphasis>, a wild tropical medicinal plant: Effects of indole-3-butyric acid (IBA) on stem cuttings

In this study we investigated the rooting ability and the growth performance of juvenile single-node leafy stem cuttings of Litsea monopetala (Roxb) Pers. collected from two mature mother trees preserved in the hill forest of Chittagong district, Bangladesh. The rooting ability of cuttings was studied under 0%, 0.1%, 0.2% and 0.4% indole-3-butyric acid (IBA) treatments. Significantly better rooting response (p ≤ 0.05) was observed with 0.1% IBA compared to control (0% IBA). The mean number of roots and the length of the longest root of cuttings in different treatments showed no significant difference (p≤0.05). After transfer into polythene bags from non-mist propagator, rooted cuttings treated with 0%, 0.1% and 0.2% IBA demonstrated the highest (100 ± 0.00%) survival capacity. The mean number of shoots developed in cuttings in the polythene bags in first three weeks varied significantly (p≤0.05) among the treatments. Effects of three fertilizer treatments, viz. T0 (no fertilizer), T1 (10g Urea, 20g TSP, 10g MOP dissolved in 1 L water) and T2 (10g Urea, 20g TSP, 10g MOP dissolved in 2 L water) on initial growth ofstecklings were also measured over a 90-days period. The increment of leaf area of stecklings was significantly higher (p≤0.05) under T0 compared with that under T1 and T2 while the increment of stem length, collar diameter and root biomass varied insignificantly among different fertilizer treatments. The results suggest that rooting juvenile single-node leafy stem cuttings could be an effective mean of regenerating L. monopetala. The application of 0.1% IBA concentration is recommended for rooting of juvenile leafy stem cuttings and application of fertilizer appeared unnecessary for the subsequent growth of stecklings in polythene bags.     

银杏枝条部位和年龄对不定根形成的影响及其与非结构碳水化合物含量的关系

[目的]研究银杏枝条部位、年龄对不定根形成的影响,并探讨其相应的叶、茎段中非结构碳水化合物(NSC)含量变化与扦插生根的关系。[方法]以50年生银杏树冠上、下部枝条的1、2和3年生位置的茎段为材料截取插穗,500 mg·L-1IBA与纯水对照处理基部60 s,在全光喷雾状态下研究扦插生根情况,并利用HLPC法分析相应部位叶和茎段中NSC含量。[结果]表明:银杏扦插不定根形成过程分为4个阶段,即0～4周愈伤形成期、4～6周愈伤膨大期、6～8周不定根开始形成期、8周后不定根伸长;生根部位主要在切口处。树冠上、下部位插穗的生根率未见明显差异,但随着枝龄的增加而明显降低。NSC分析表明:下部叶片NSC组分中多糖和总糖含量明显高于上部的,但茎段NSC的所有组分在上下部均无明显差异;随着枝龄的增加,相应位置叶片NSC各组分含量没有明显差异,但相应茎段NSC组分中葡萄糖、果糖、多糖、总糖、淀粉含量却明显降低,与生根率的变化趋势一致。此外,500 mg·L-1IBA处理并未明显提高生根率,还需进一步优化处理浓度。[结论]银杏树冠上部和下部枝条对不定根形成无影响;未处理枝条的枝龄与生根率呈负相关,而茎段NSC含量与生根率呈正相关;叶片NSC含量对不定根形成影响较小;生根方式以愈伤生根类型为主。该结论将为今后银杏扦插生根及其机制研究提供参考。     

Restoration of rooting competence in mature Faidherbia albida,a Sahelian leguminous tree,through serial root sucker micrografting

Faidherbia albida is an essential leguminous tree of arid areas of Africa which is widely used in agroforestry. This species naturally produces root suckers. Their morphogenetic ability has been used to initiate a rejuvenation/reinvigoration process in mature subjects. The proposed method contains two stages. The first stage generates the first ramets : our results have shown that suckers picked from root cuttings are more vigorous than explants taken directly from the crown of adult subjects. The second stage furthers the rejuvenation process through cycles of repeated micrografting onto juvenile rootstock, which have been grown in vitro. As early as the third cycle, a significant increase in reactivity is gained. This is determined by growth of the scion and the rooting competence of microcuttings severed from the scions after each micrografting cycle. At that point, the rooting competence is completely restored. So, this sequential method, (i) suckers from root cuttings, (ii) repeated micrografting, seems valid as a technique for the restoration of rooting competence in mature F. albida with a view to its cloning.     

Vegetative propagation of Colutea istria Mill. from leafy stem cuttings

This study investigates the optimal conditions for the vegetative propagation of the multipurpose leguminous shrub Colutea istria from leafy stem cuttings. The conditions examined included 1) the origin of the cutting (apical, medial or basal), 2) indole-3-butyric acid (IBA) treatment (0, 50, 200 or 400 mg/l), 3) the relative humidity of the propagation environment (high or low), 4) wounding base of cutting, and 5) the season in which the cutting was taken. The rooting ability of the cuttings was significantly influenced by all these factors. Winter cuttings obtained from the middle and base of the branch showed a greater rooting capacity than those harvested from the apical area, while autumn cuttings harvested from the middle and apical areas of the branch showed a greater rooting capacity than those harvested from the base. Winter cuttings showed the best rooting capacity than autumn cuttings. IBA treatment (200 mg/l), high humidity (98-100%), and wounding increased the rooting capacity of the cuttings. The sprout of new leaves was higher in basal cuttings, while IBA and wounding also significantly enhanced the root number of rooted cuttings. A method for vegetatively propagating C. istria plants is given.     

灰楸无性系生长和形质性状变异与选择

[目的]本研究考察了灰楸无性系生长(树高、胸径、单株材积)和形质(分枝度、分枝角、冠幅、树皮厚度、尖削度)性状,为灰楸优质用材良种选育和定向培育提供理论依据。[方法]以5年生灰楸试验林33个无性系为材料进行多个性状的遗传变异分析、方差分析、重复力估算。利用主成分分析和隶属函数法综合选择优良无性系。[结果]灰楸树高、胸径、单株材积在无性系间差异显著或极显著,其重复力为0.456～0.592。灰楸形质性状中,平均尖削度P1和P3在无性系间存在显著或极显著差异,且具有中等大小的重复力(0.479和0.415)。遗传相关分析中,单株材积与冠幅、树皮厚度、平均尖削度P1等存在显著或极显著较弱的正相关,相关系数为0.178～0.263。针对不同育种目标,利用主成分评价和隶属函数法最终选择出特定的优良无性系。[结论]5年生灰楸无性系间各性状存在丰富的遗传变异,且生长性状受到中等的遗传控制,有较好的遗传改良潜力。灰楸无性系生长性状与形质性状具有独立性,可进行单独定向选择。灰楸无性系H3-1-9、H3-1-18、H3-1-10、H3-1-3、H3-2-16和H3-1-17可作为速生丰产良种;无性系H3-1-16、H3-1-19、H3-2-12和H3-2-9可作为优质用材的无性系;无性系H3-1-17、H3-1-10、H3-1-18和H3-2-16可考虑作为生长和形质综合改良的灰楸无性系在当地推广。     

Clonal propagation of <Emphasis Type="Italic">Dalbergia sissoo</Emphasis> Roxb. and associated metabolic changes during adventitious root primordium development

A study was conducted on the twelve clones of shisham (Dalbergia sissoo Roxb.). These clones were obtained from India and Nepal. Single-node leafy cuttings were prepared from the vegetative multiplication garden to examine the clonal variation, effect of IBA treatment on rooting response and associated metabolic changes during adventitious root formation. A remarkable and significant variation was observed due to treatment of 2,000 ppm IBA in the rooting parameters. Clonal variations were also significant for root and shoot growth while length of root was insignificant. Among the twelve clones studied; C3 (Tulsipur, Gonda, Uttar Pradesh, India) and C4 (Laxmipur, Gonda, Uttar Pradesh, India) clone cuttings have given the highest rooting response. Interaction (clone × IBA) was significant only for production of number of roots per cutting. Periodic sampling for clone C3 was performed at 0, 7, 14, 21, 28 and 35 days to examine the contents of total soluble sugars, starch, protein and peroxidase (PER) activity in the rooting zone of cuttings (∼0.5 cm) during adventitious root primordium development. A significant increase in all the metabolic activities was noted due to IBA. Total soluble sugars and starch contents of cuttings decreased with the passage of time. Protein content and PER-activity started to increase in the early stage and reached the highest level on day 21, followed by a decline at the 35th day of sampling. These trends were common for both IBA treated and untreated cuttings. Protein content and PER-activity remained higher in the rooting zone of IBA treated cuttings. Overall these findings suggested that exogenous application of IBA may have activated carbohydrate metabolism for release of energy, while protein and PER-activity were necessary for cell division and differentiation during adventitious root primordium initiation and development in the rooting zone of cuttings.     

杨树新无性系扦插生根特性的研究

以杨树新无性系ＮＬ－８０１０６、ＮＬ－８０１２１和ＮＬ－８０３５１为材料，从解剖学角度研究其插插生根的机理。结果表明，无性系ＮＬ－８０１０６的生根能力较ＮＬ－８０３５１强；插穗的不定根原基在母株生长早期形成，起源于射线与形成层交叉处；不定根原基的数量随着苗高的增长而增多；但插穗的生根能力与不定根原基的数量关系不大。     

Root initiation of Shorea macrophylla cuttings: Effects of node position,growth regulators and misting regime

Single-node leafy cuttings from 8- and 15-month-old seedlings of the large Bornean Dipterocarp Shorea macrophylla (Illipe nut) rooted easily under continuous mist, both with and without the application of auxins. Callus production was greatest in the untreated cuttings. Rate of rooting was enhaced by 1200 ppm and 3600 ppm IBA, but the overall level of rooting after 61 days was unaffected by auxin treatment. In a second experiment, 3600 ppm IBA was found to be more effective than 3600 ppm NAA and mixtures of 1800 ppm NAA + 1800 ppm IBA. Mortality of cuttings was greatest with IBA especially at 10800 ppm. Cuttings from the second node below the apex rooted best, with rooting ability of those from nodes 3, 4 and 5 being progressively worse, and mortalities rising with distance from the apex. Cuttings from the uppermost node, which included the developing apex, had the lowest rooting ability. When continuous misting was replaced with misting for alternate hours, rooting was still good, but the absence of misting overnight resulted in much increased cutting mortality and, subsequently, in decreased rooting. It is suggested that Shorea macrophylla could be domesticated for fruit or timber production by the propagation of superior clones.     

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.     

Key roles of leaves, stockplant age, and auxin concentration in vegetative propagation of two African mahoganies: Khaya anthotheca Welw. and Khaya ivorensis A. Chev

Leaf area, IBA concentration and age of stockplants were all found to be important factors for successful rooting for vegetative propagation using single-node cuttings of the two main African mahogany species: Khaya anthotheca and K. ivorensis. Cuttings with leaf area of 30–50 cm² had the best rooting percentage and cuttings with about 30 cm² had the most number of roots per cutting in K. anthotheca. Khaya ivorensis, cuttings with 10–30 cm² leaf area had the highest rooting percentage. Cuttings collected from 1-year-old stockplants recorded the highest rooting percentage and largest number of roots per cutting. Cuttings from 3-year-old stockplant of the same seeds sources had the lowest rooting suggesting aging negatively impacted rooting ability. The effect of auxin concentration, on rootability was examined with cuttings of K. anthotheca. An IBA concentration of 0.8% was the best exogenous auxin concentration for percentage rooting, number of roots per cutting and the length of the longest root per cutting.