Influence of growth hormones on adventitious root formation in semi-hardwood cuttings of <Emphasis Type="Italic">Celasturs paniculatus</Emphasis> Willd.: a contribution for rapid multiplication and conservation management

Celastrus paniculatus Willd. (Celastraceae) is an important medicinal tree valued for its seeds. Indiscriminate collection of this plant from the habitat zones has posed a serious threat to its existence in the wild, results in globally a threatened plant species. Ex situ conservation is a prioritized agenda of research for redlisted plant species. Semi-hardwood stem cuttings collected from 10 to 15 year old trees were treated with different concentrations (0, 0.5, 1.0, 2.0, 3.0, 4.0 and 5.0 g l⁻¹) of growth hormones; indole-3-acetic acid (IAA), indole-3-butyric acid (IBA) and 1-naphthalene acetic acid (NAA) for positive effect on root induction. After 90 days of treatment, results were analyzed for percentage of rooting, root number and average root length per rooted cuttings. The highest rooting (57%) response with highest number of roots (~77.2) was obtained in indole-3-acetic acid at 3.0 g l⁻¹. Overall, high significant (P ≤ 0.05) rooting response was noticed in IAA treatment comparative to hormones IBA and NAA. Rooted cuttings exhibited 100% survival in the experimental field. This study reveals the propagation of semi-hardwood cuttings derived from partially matured branches is possible and it provides a basis for conservation of this threatened plant species by reducing pressure on its natural populations.     

Effects of mother tree ages,different rooting mediums,light conditions and auxin treatments on rooting behaviour of <Emphasis Type="Italic">Dalbergia sissoo</Emphasis> branch cuttings

Dalbergia sissoo Roxb. is one of the promising multipurpose tree species of South Asia. Most of the plantations of D. sissoo from seeds are facing severe threats due to the die-back disease, which ultimately causes death of this potential tree-species within a few months. Vegetative propagation could avoid the die-back disease. Thirty mother trees of different age-groups of D. sissoo were selected for evaluating the rooting behaviour of branch cuttings from D. sissoo as influenced by auxins (IAA or IBA at 100, 200, 500 mg·L⁻¹), ages of mother trees (10, 4 and 2 years old) and different environment conditions, i.e., different mediums (soil and sand) or light conditions (in shade and open condition). The results show that application of IAA and IBA induced more numbers of cuttings (collected from 10-year-old mother trees) to root compared to control. Branch cuttings of D. sissoo collected from 10-year-old mother trees and planted in soil bed in open conditions had 100.0% of cuttings to root in IAA (100 mg·L⁻¹) and IBA (200 mg·L⁻¹) treatments. Both rooting medium (Soil and sand) influenced significantly (p<0.05) on rooting response of branch cuttings. Soil medium was found to achieve maximum no. of branch cuttings to root, compared to sand medium.     

Vegetative propagation of the threatened African wild olive [Olea europaea L. subsp. cuspidata (Wall. ex DC.) Ciffieri]

A rapid vegetative propagation method is described for Olea europaea L. subsp. cuspidata [Wall. ex DC.) Ciffieri (syn. Olea africana Mill.)]. Leafy branch cuttings were harvested from 6 to 7-month-old stecklings (= plants derived from rooted cuttings). Cuttings 2–3 mm in basal diameter were trimmed to 70–100 mm in length, with leaf areas reduced to 15–33 cm². Indolebutyric acid (IBA) was applied at 0, 10, 20, 25, 30, 35 and 40 µg/cutting to each of the 70–80 replicate cuttings randomly allocated to each of the 7 treatments. Callusing and rooting occurred 3–5 and 5–7 weeks after treatment, respectively. The rooting success of cuttings treated with 20 or 40 µg IBA/cutting was 75 and 90%, respectively. Differences in rooting success, speed of rooting and root numbers between the control and the IBA treatments were significant (p < 0.01). Compared to seedlings of similar shoot height, rooted cuttings grew significantly (p < 0.01) faster and produced more biomass. It is concluded from this study that the rooting of leafy branch cuttings derived from young stockplants of wild olive is rapid, and that vegetative propagation is an effective means of regenerating this valuable, yet threatened, tree species.     

Physiological studies for tropical tree improvement and conservation. Factors affecting root initiation in cuttings of Triplochiton scleroxylon K. Schum.

Applying auxins to freshly cut basal ends of leafy single-node cuttings of Triplochiton scleroxylon, an important timber tree of West Africa, considerably enhanced rooting percentages. The optimal concentrations in 10 μl MeOH droplets of a 50 : 50 mixture of α-naphthalene acetic acid (NAA) and indole-3-butyric acid (IBA) ranged from 8–40 μg according to clone. Larger amounts, which tended to increase numbers of roots per rooted cutting, inhibited root production in some clones. When applied singly, IBA was more effective than NAA in most clones.Leafless cuttings rarely rooted even when treated with auxins. Rooting occurred following the retention of 5 cm² of leaf lamina, and was maximal, as judged by rooting percentages, with 50 cm². The inability of leafless cuttings to root was associated with the rapid depletion of all carbohydrates in stem tissues, while those in unshaded leafy cuttings tended to increase.Percentages of cuttings rooting increased when temperatures of propagating-beds were raised above 20°C, and 28°C was optimal for most clones, especially if treated with auxins. Cutting survival declined above 28°C, although up to 38°C surviving cuttings rooted equally well.     

Vegetative propagation of Dalbergia sissoo: effect of growth regulators, length, position of shoot and type of cuttings on rooting potential in stem cuttings

The effect of auxins (IAA or IBA at 100,200,500 mg L 1) on rooting and sprouting parameters differed significantly (p < 0.05).Rooting and sprouting percentages were higher in some treatments while other parameters were significantly higher in other treatments.The results of the present study revealed that rooting was significantly (p < 0.05) affected by the length of cuttings,as well as the position of shoots and type of cuttings.On average,86.0 per cent rooting was observed in the 30-cm long cuttings compared to the other two lengths of cuttings,i.e.,20 and 25 cm,irrespective of any auxin treatment.In a control set,without any auxin treatment,a maximum of 60.0% rooting was recorded in the 30-cm long cuttings and a minimum of 40.0% of the cuttings rooted in the 20-cm long cuttings.Similarly,cuttings collected from the lower and upper portions of shoots resulted in 72.5 and 52.5 per cent rooting respectively,irrespective of auxin treatments.Maximum rooting was observed in the lower portion (40.0%) of cutting compared to the upper portion (30.0%) in the control set without auxin treatment.Leafless branches produced maximum (72.0%) rooting compared to the leafy cuttings (35.0%),irrespective of the auxin treatment.The leafy cuttings produces a minimum of 15.0% sprouting and rooting in the control set.     

Effects of different genders and hormones on stem cuttings of Salix anatolica

ABSTRACT

Salix anatolica Ziel. & D. Tomasz., belonging to Salicaceae family, is endemic to the East Mediterranean in Turkey. Its threat category has been assessed as vulnerable based on the red list criteria of IUCN. Therefore, it is necessary to protect and reproduce. Within the scope of this study, propagation of the species is carried out by cutting which is one of the vegetative propagation methods. Under greenhouse media conditions, effects of different concentrated doses of auxins were examined on rooting percentage (RP), number of roots (RN) per rooted cuttings, and root length (RL) related to male and female stem cuttings. At the end of this study, the highest RP in the cuttings taken from the female individuals was 100% in Control and IAA 1000 ppm treatments, this value was also obtained as 100% in Control + Wounding and IAA 1000 ppm treatments in the cuttings taken from the male individuals. While hormone applications were effective on the RP in male individuals, they were effective on the RN and RL in female individuals. In addition, wounding has had a positive effect on both male and female individuals.     

几种柏科树种嫩枝扦插的研究

木本植物的插条繁殖至今仍是园林工作者获得良种无性系和培育苗木的重要途径。柏科树种多是珍贵的园林树种,它们的嫩枝插穗生根难易差别很大。本研究探讨了生根难易的生理原因,为提高扦插成活率提供理论依据。     

Adventitious rooting in shoot cuttings of Azadirachta indica and Pongamia pinnata

Adventitious rooting in shoot cuttings of neem (Azadirachta indica) and karanj (Pongamia pinnata) was investigated in different seasons. The influence of auxins and B-vitamins (neem only) was evaluated. Maximum rhizogenesis coincided with the emergence of new sprouts i.e. February (neem) and March (karanj). Considering both rooting percentage and root biomass, IBA was the most effective auxin tested. Compared to auxin free controls, IBA (1000 ppm in neem and 800 ppm in karanj) significantly increased adventitious rooting percentage (80 to 100 % respectively), the numbers of roots and root biomass for both species. In neem, B-vitamin treatment yielded 40–50% rooting for cuttings. This was significantly greater than rooting for controls but equivalent to IAA treatments. In neem, some of the cuttings treated with 2000–3000 ppm IBA had well developed root systems without any sprouts. In karanj, all auxin treatments promoted sprouting. The level of total soluble sugars in the rooting zone of neem and karanj was higher in non-rooted than rooted cuttings.     

Temporal variation in rooting of <Emphasis Type="Italic">Annickia chlorantha</Emphasis> leafy stem cuttings

The effects over time of exogenous auxins and substrate on rooting of leafy stem cuttings were simultaneously examined in Annickia chlorantha. The hypothesis that post-severance treatments and propagation environment do not temporally affect the rooting ability of leafy stem cuttings was rejected. Each of the four replicate blocks used consisted of 12 treatments from two crossed factors, substrate × auxins. Time (weeks) after insertion of cuttings in nonmist propagators was used as the third factor. Substrate × auxin × time had highly significant (P = 0.0022), whereas substrate × time and auxin × time had non-significant (P = 0.0518–0.0549) effects on rooting percentage, respectively. Substrate and auxin did not influence rooting ability. Time had highly significant (P < 0.0001) effects on rooting ability. Contrasts constructed with the different factors tested on rooting percentage allowed the dissection of the rooting period into three phases.     

激素处理南方红豆杉扦插生根的研究

应用吲哚乙酸、吲哚丁酸、奈乙酸三种不同的生长素对插条进行处理,探讨它们在不同扦插基质上的生根率。基质配比采用（４,４）单形重心设计,结果重心设计,结果是：三种生长素中以吲哚乙酸对扦插生根的影响最好,基质以４５％黄心土和５５％珍珠岩配比效果最好。插穗浸泡时间不同对扦插生根率也产生了显著影响。     

Metabolic changes during adventitious root primordium development in <Emphasis Type="Italic">Tectona grandis</Emphasis> Linn. f. (teak) cuttings as affected by age of donor plants and auxin (IBA and NAA) treatment

Aging of the donor tree decreased adventitious root formation in shoot cuttings of Tectona grandis Linn. f. (teak). Exogenous application of auxins, i.e., α-naphthalene acetic acid (NAA) and indole-3-butyric acid (IBA) has a significant positive effect on the percentage of rooting. The maximum percent rooting was obtained with 4,000 ppm IBA as compared to other treatment. Significant increase in root number was recorded in shoot cuttings treated with 4,000 ppm NAA. The overall rooting response was better in the treatment with IBA rather than with NAA. Further periodic samples (0, 10, 20, and 30 days) were taken to assess the total soluble sugar, starch, protein, and peroxidase (PER) activity in the rooting zone of shoot cuttings of teak during adventitious root formation. Application NAA and IBA to shoot cuttings resulted in an increase in the level of total soluble sugar, starch, protein, and PER-activity in the rooting zone. The stored carbohydrates were utilized during adventitious root formation. Hence, total soluble sugar and starch contents of cuttings, irrespective of age of donor plants, decreased with the passage of time in cuttings planted for rooting. Significant fluctuations were observed in the protein content of cuttings during the time of root induction. There was an increase in the protein content with the passage of time from the day of planting up to its 20th day, followed by a sharp decline in the protein content of cuttings at the 30th day of planting, irrespective of the age of donor plants or the treatment of cuttings with auxins. Irrespective of donor plant age, PER-activity in the cuttings increased from the day of their planting for rooting up to the 20th day, and then declined at its 30th day of planting. It was interesting to note that PER-activity remained higher at all stages in the cuttings of 2-month-old seedlings which rooted profusely as compared to the cuttings of 15- and 30-year-old donor plants those rooted poorly. This study suggested that the exogenously applied NAA and IBA at different concentration seems to activate sugar metabolism for release of energy, protein and PER-activity which are necessary for cellular division and differentiation during adventitious root primordium initiation or development in the rooting zone of shoot cuttings.     

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.     

Hormone level analysis on adventitious root formation in Eucalyptus globulus

Eucalyptus globulus is the one of the most economically important trees for pulp and paper industries due to its fast growth and short harvesting cycle. However, E. globulus is well known as a woody plant that is hard to propagate vegetatively. In this study, we found wide distribution of rooting ability among seven independent genotypes we tested. Analysis of the mechanism of adventitious rooting by using the auxin transport inhibitor, N-naphthylphthalamic acid, revealed that polar auxin transport is crucial in root formation. The gravitropism of the stem was highly correlated to the percentage of adventitious root formation. Hormonal analysis showed that the levels of indole-3-acetic acid (IAA) were the same between difficult-to-root and easy-to-root genotypes, whereas levels of IAAsp (indole-3-acetyl aspartic acid) were higher in the difficult-to-root genotype, indicating that IAA metabolism might play an important role in adventitious root formation in this species. Levels of several cytokinins exhibited differences between genotypes that varied in their cutting performance and rooting ability. Furthermore, higher level of cytokinin in elongating shoots were correlated with rooting percentage. Taken together, our results indicate that both auxins and cytokinins play a role in adventitious root formation in E. globulus, and that a complex interplay between the levels of auxins and cytokinins and their metabolism might result in root formation in this commercially important plant.     

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.     

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.     

Clonal propagation of Pterocarpus santalinoides L'Hér. ex DC.: the effect of substrate,cutting type,genotype and auxin

Pterocarpus santalinoides is a multipurpose tree species, native to Africa and South America. However, excessive pruning for fodder is jeopardising its seed production leading to poor regeneration in the Sahel region. Efficient vegetative propagation techniques may overcome this concern. To address this issue, four experiments were conducted to determine the effects of substrate (Experiment 1), cutting type (Experiments 2 and 3), genotype (Experiment 4) and auxins (Experiments 1, 2, and 4) on rooting ability in a non-mist propagating unit in Mali. Among the four tested substrates, no significant differences were found in rooting parameters, including the percentage of rooted cuttings, the number of roots and secondary roots per rooted cutting, and the length of the longest root per rooted cutting. Semi-hardwood cuttings rooted significantly better than softwood cuttings with a higher percentage of rooted cuttings (31.7?±?6.5% vs. 9.2?±?2.7%), greater number of roots (8.2?±?4.8 vs 1.5?±?0.7), greater number of secondary roots (16.7?±?4.2 vs 4.6?±?1.8) and longer root length (17.8?±?12.0?cm vs 2.3?±?1.0?cm) per rooted cutting. In addition, one-node cuttings cut below the second and third nodes, respectively, had the highest rooting success (88% and 90%, respectively) followed by cuttings cut below the fourth node (68%) and the first node (62%). Significant differences in the percentage of rooted cuttings were found among 12 randomly selected genotypes with rooting varying from 2% to 75%.The results also showed that auxin application, especially IBA, had a significant effect on rooting success, the number of roots and secondary roots per rooted cutting. Single-node cuttings, and cuttings of 10?cm length with multiple softwood and semi-hardwood nodes, can be used with or without auxin treatment for successful clonal propagation of P. santalinoides. The results of the present study indicated that P. santalinoides is amenable to clonal propagation using low-cost propagators and sand-based rooting media.     

Vegetative propagation of twelve fodder tree species indigenous to the Sahel,West Africa

In the Sahel region, many woody species are used as fodder because of their high nitrogen content, especially during the dry season, in contrast to grasses and crop residues. Unfortunately, this resource is being threatened by regular pruning, increasing livestock browsing and impeding their natural regeneration. Therefore, there is a need to find appropriate regeneration options to sustain fodder production. Thus, a series of vegetative propagation experiments were conducted to identify the most appropriate multiplication methods of some of the species used as fodder. This series included testing the effects of naphthalene acetic acid (NAA) and indole butyric acid (IBA) on rooting ability of stem cuttings of 12 species: Afzelia africana, Balanites aegyptiaca, Bauhinia rufescens, Commiphora africana, Faidherbia albida, Ficus gnaphalocarpa, Guiera senegalensis, Kigelia africana, Pterocarpus erinaceus, Pterocarpus lucens, Pterocarpus santalinoides and Terminalia avicennioides. The series also evaluated the impacts of the size (C. africana) and the age (P. erinaceus) of the cuttings on their rooting success. Pterocarpus santalinoides was revealed to be an easy-to-root species, showing a high percentage of rooted cuttings (up to 88±3%), followed by P. erinaceus, P. lucens and B. aegyptiaca (up to 37±4%, 31±5% and 26±6%, respectively), in contrast to A. africana, cuttings of which did not root at all. The application of NAA and IBA enhanced the number of roots and secondary roots per rooted cutting. Large-diameter cuttings (15–20?mm) of deeply planted C. africana gave the highest percentage of rooted cuttings (78.3±4.4%). Tree pruning improved the rooting capacity of cuttings collected from P. erinaceus with one-month resprouts giving the highest percentage of rooted cuttings (50.0±6.7%). These results indicate that P. santalinoides, C. africana, P. erinaceus, P. lucens and B. aegyptiaca are amenable to vegetative propagation as an alternative to sexual propagation.     

Vegetative propagation of African Mahogany: effects of auxin, node position, leaf area and cutting length

Applied auxin, node position, leaf area and cutting length were examined to investigate the requirements for rooting stem cuttings of Khaya ivorensis. All these variables were shown to be important factors affecting rooting, confirming the hypothesis that successful rooting can be achieved if these primary variables are optimised.The best concentration of the auxin IBA was found to be 200 g per cutting, which hastened rooting, increased the percentage of cuttings rooted and increased the number of roots per cutting. One clone (8013) was unresponsive to auxins in terms of the percentage of cuttings rooted, but was the most responsive in terms of the numbers of roots per cutting. A greater percentage of cuttings from basal nodes were rooted than from apical nodes. Cuttings cut squarely at the base produced a radially-arranged root system, whereas an oblique cut resulted in a one-sided root system.Trimming the leaf area of cuttings to 10 cm² gave greater rooting percentages than trimming to 100 cm². In general, long cuttings (39 mm) rooted better than short cuttings (19 mm), however, there was an interaction between leaf area and cutting length, in which cuttings with short stems and large leaves had the lowest rooting percentage.     

Vegetative propagation of Aesculus indica through stem cuttings treated with plant growth regulators

Cuttage propagation of Aesculus indica was tested by treatments with different concentrations of indole-3-acetic acid (IAA) @ 2000, 4000 (ppm), indolebutyric acid (IBA) @ 2000, 4000 (ppm) and naphthlcetic acid (NAA) @ 2000, 4000 (ppm) in dry formulation in the Forest Nursery, Faculty of Forestry, SKUAST-K, Shalimar. The cuttings treated with IBA @ 4000 ppm and IBA @ 2000 ppm had a sprouting rate of 75% and 50%, respectively, which was significantly higher than that of control and other treatments. The highest rooting rate (50%) was recorded in the cuttings with the application of IBA @ 4000 ppm. The cuttings treated with IBA @ 2000 ppm had 25% rooting rate. All other treatments along with control (talc powder) failed to induce rooting. It was concluded that IBA @ 4000 ppm was a better-applied concentration for vegetative propagation of A. indica under Kashmir conditions. Biography: Mumtaz Majeed (1980– ), male, post graduate in Faculty of Forestry, Sher-e-Kashmir University of Agricultural Science & Technology, Shalimar, Srinagar - 191 121, J&K, India.     

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.