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1.
Abolfazl Daneshvar Mulualem Tigabu Mostafa Farhadi Per Christer Odn Asaddollah Karimidoost 《林业研究》2014,25(4):827-834
Dwarf mistletoes are parasitic flowering plants that infect conifers, resulting in substantial loss of growth and mortality. Recently, forest managers in Iran are contemplating whether infection of Juniperus polycarpos C. Koch forests by dwarf mistletoe, Arceuthobium oxycedri （DC.） M. Bieb, influences tree vigor and contributes to insuffieient natural regeneration. The present study aimed at assessing the severity of infection and its impact on growth and reproductive output of./., polycar- pos. Infected and uninfected trees （n =20 each） were selected for assess- ment of diameter, height, crown area, and crown volume as well as quantity and quality of cones and seeds. The severity of infection of trees was determined by Hawksworth＇s 6-class dwarf mistletoe rating （DMR） system. The DMR system revealed that 40% of the infected sample trees were lightly infected （DMR =1-2） and 60% were moderately infected （DMR =3--4）. Growth characteristics did not differ significantly （p 〉 0.05） between infected and uninfected trees. However, moderate infec- tion affected the reproductive output of./. polycarpos by significantly （p 〈0.05） reducing the mean number of cones per unit area of the crown, increasing the number of damaged seeds, and reducing seed size and seedgermination capacity. We conclude that reproductive output of J.. poly- carpos is more sensitive than growth characters to moderate infection by juniper dwarf mistletoe, and this might partly account for poor natural regeneration. 相似文献
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有性繁殖与无性繁殖相结合,建立轮回采穗圃,用全光自控喷雾扦插技术,大规模推广优良家系和第2代优良单株,是加快落叶松树种改良进程的关键。本文还提出了营建落叶松扦插苗人工林、测定林及采穗圃的方法和步骤。 相似文献
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Juniperus procera Endl. is economically important timber species, but its populations are extremely small and fragmented in its natural habitat, thus, calling for immediate ex situ conservation. Here we examined the effects of seed sources and storage temperature on the longevity of Juniperus procera seed lots through collection and preservation of seeds in seed banks. Seeds were collected from nine sites across the species natural distribution in Ethiopia and stored in four warehouses: modern cold room (5℃), mud house (15℃), concrete block house (17℃ or corrugated iron house (20℃) for 42 months. Every three months, a random sample of stored seeds were drawn and tested for germination. A highly significant variation (p < 0.01) in germination of stored seeds was observed among different storage environments, seed lots, and duration of storage. Over the storage period, seeds stored in the cold room had the highest mean percentage germination, followed by the mud house, corrugated house and blocket house. The cold room (41%) and the mud house (38%) maintained the same level of germination as the intitial germination of the seedlotds (42%). The variation in longevity of stored seeds was significnatly correlated with the initial germination of seed lots (r > 0.80; p < 0.01). Cold storage also resulted in enhancement of germination through its stratification effect that terminated the non-deepphysiological dormancy of juniper seeds. In conclusion, seed lots with good initial germination can be effectively stored in cold room (5℃) up to four years. In the absence of modern cold stores, mud houses can be used as a good alternative to store seeds at local level. 相似文献
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Seeds of Juniperus procera collected from five provenances across its geographic range in Ethiopia were subjected to cold-moist stratification at 5°C
or 10°C for 6–12 weeks. The effect of aqueous smoke solution in overcoming the light requirement for germination, and the
potential of visible (VIS) and near infrared reflectance (NIR) spectroscopy for sorting sound and insect-damaged seeds were
also investigated. Highly significant differences in germination were detected among provenances (P < 0.0001) and stratification periods (P < 0.0001), but not between temperature regimes (P=0.111). Seeds from the south and southeast distribution ranges had higher percentage germination after 6 weeks of stratification
than seeds collected from north, northwest and central ranges of distribution. The smoke treatment did not affect germination
regardless of whether the seeds were exposed to light. Exposure to light increased germination capacity three fold. Sound
and damaged seeds were distinguished with 90% accuracy using VIS + NIR spectroscopy. It can be concluded that dormancy in
juniper seeds varies with provenances, and cold stratification for 6 weeks alleviates dormancy in some seed lots. Tentatively,
smoke treatment seems ineffective in overcoming photo-dormancy in juniper seeds. VIS + NIR spectroscopy has demonstrated a
great potential for sorting damaged seeds, thereby upgrading seed lot purity. 相似文献
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Catherine Ky-Dembele Jules Bayala Antoine Kalinganire Fatoumata Tata Traoré Bréhima Koné Alain Olivier 《Southern Forests》2016,78(3):193-199
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. 相似文献
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Catherine Ky-Dembele Mulualem Tigabu Jules Bayala Sibiri Jean Ouédraogo Per Christer Odén 《Forest Ecology and Management》2007
Savanna plant species are capable of regenerating both sexually and asexually. The importance of each regeneration mechanism depends on the species, the type and the intensity of disturbance. This paper describes the relative importance of sexual and asexual regeneration for the restoration of a selectively cut savanna woodland in Burkina Faso. Plantlets regenerated sexually or asexually were determined by excavating the below ground system and assessing basal and aerial sprouts within 144 quadrats along transects in 2, 5, 10 year-cut and control plots. The result shows that seedling sprouts were predominant (83%) compared to root sucker (4%), coppice (5%), water sprout (2%) and layering (less than 1%). True seedlings constituted a minor component (5%) of the plantlet population. A total of 54 woody species was found in the plantlet population with 52 presenting seedling sprouts. Twelve species were found regenerating from both seeds and root buds; of which Dichrostachys cinerea, Pteleopsis suberosa and Detarium microcarpum had the highest number of plantlets. Feretia apodanthera was the only layering species encountered in the sampled area. Coppices, root suckers and water sprouts showed higher height and bigger collar diameter compared to seedling sprouts and true seedlings. It can be concluded that sexual reproduction is the dominant mechanism of seedling recruitment in this disturbed savanna-woodland, and that its success relies on the ability of plantlets of seed origin to resprout abundantly. 相似文献
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In South-western Morocco, the argan tree (Argania spinosa) is basis of a traditional agroforestry system. However, this system is no longer at equilibrium and there is an urgent need
to renovate it. The natural reproduction of the tree has become difficult, and most attempts of artificial regeneration have
failed. We have assessed three different propagation methods: seedlings, cuttings, and in-vitro micro-propagation. Our experiments, involving several seed collections, showed that germination occurred easily when using
young (< 12 months) and large seeds (nut weight > 3 g). Nuts with thin walls germinated better than nuts with thicker walls.
Sterilization prevented microbial contamination and improved germination. Vegetative propagation of the argan tree by cuttings
was tried using lignified cuttings collected from adult trees or young stems from managed stockplants (three years old). Rooting
rate seems to be dependent on genotype, and the best results were obtained from young stems sterilized to avoid fungal contamination.
The success of in-vitro micro-propagation is also highly genotype-dependant. We developed a modified medium enabling up to 80–95% rooting rate for
some clones. However, other clones were still recalcitrant. Whatever the propagation method used, special attention must be
paid to the architecture and growth of the root system.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
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青钱柳属难生根树种,生根率低,扦插繁殖是无性繁殖的重要技术,已广泛应用于苗木生产中,研究青钱柳扦插生根问题对其产业化育苗具有重要意义.该文主要从扦插的生根机理、生根的影响因素方面进行了综述,重点讨论了:(1)扦插繁殖技术研究进展;(2)扦插生根解剖学和生理生化研究;(3)插穗的位置效应、温湿度和基质.最后提出应该从生长素调控机制、几种重要氧化酶活性及其含量、营养物质和形态解剖学4个方面进行深入研究. 相似文献
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本文报导西加云杉优树离体复壮与无性繁殖。低温预处理（２℃，１－３０天）促进休眠顶芽破裂和自由生长芽形成。Ｃ型外植体为最佳接种类型。连续继代培羊可改进复壮效应，腋芽和不定芽再生率。目前还未找到有效试管内生根法。组培嫩梢扦插生根率可达７５％以上。大量部分复壮组培苗已成功移入温室，经园艺生理和外源植物生长调节物质处理，可为生产提供大量扦条，实现快速大量繁殖。 相似文献
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Vegetative propagation techniques are recognized as indispensable tools for mass multiplication of important multipurpose
trees adopted in different agroforestry systems. Albizia procera, one among important species, is difficult to propagate commercially either by stem / root cuttings or layering. A study
was undertaken to develop procedure for its in vitro regeneration through organogenesis. Explants collected from 15±2 yr-old mature plus trees and from 15 days old juvenile seedlings
were regenerated with exogenous application of different hormones. Epicotyl and hypocotyl explants excised from juvenile seedlings
showed higher callusing than axillary bud and shoot tip explants derived from mature trees. Benzylaminopurine (BA) at 3 μg/l
was most effective, which induced hundred percent callusing in epicotyl and hypocotyl explants in 1/2 Murashige and Skoog
(MS) medium. Callus originated from axillary buds and apical shoot tips of mature trees failed to form organs, however callus
derived from epicotyl and hypocotyl explants proliferated and formed de novo shoots and leaflets. A concentration of 3 μg/l of BA was found effective for shoot proliferation. Shoots grew vigorously
in 2 μg/l gibberellic acid (GA3) treatment and rooted in 1/2 MS medium supplemented with indole-3-butyric acid (IBA) and indole-3-acetic acid (IAA). Rooting
was most successful on medium supplemented with 6 μg/l IBA alone on which 93.3% of the shoots formed roots. Sand or vermiculite
supplemented with 4 ml of yoshida solution proved as best hardening media, which recorded 70-80% survival of plantlets. One
year old tissue culture raised plants had comparatively more height, collar diameter, biomass, and root shoot ratio than plants
raised from cuttings and seeds of the same age. The procedures enumerated provide a basis for the development of in vitro techniques for rapid multiplication of A. procera.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
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云南甜龙竹（Dendrocalamus brandisii）是优异的笋材两用大型丛生竹种,但常规无性繁殖技术培育的苗木因价格高而极大地阻碍了该竹种的推广栽培。文章以云南甜龙竹种子萌发的无菌苗为外植体,研究植物生长调节剂对试管苗快速繁殖及生根的影响。结果表明：丛生芽诱导的最佳培养基为MS+6-苄氨基腺嘌呤（6-BA）3.0 mg/L+萘乙酸（NAA）0.7 mg/L,诱导率可达86.33%;最佳继代增殖培养基为MS+NAA 0.3 mg/L+6-BA 6.0 mg/L+噻苯隆（TDZ）0.001 mg/L,增殖系数可达4.90;最佳生根培养基为1/2MS+NAA 2.0 mg/L+吲哚丁酸（IBA）4.0 mg/L,生根率可达71.45%。研究结果可为云南甜龙竹工厂化育苗提供技术支撑。 相似文献
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C. Detrez 《Agroforestry Systems》1994,25(3):171-179
Shoot propagation from mature tree explants ofAcacia tortilis subsp.raddiana, a tropical tree legume, was studied. The effects of (i) the size of cuttings and (ii) a recut treatment of the donor trees, on axillary bud growth from multinodal horticultural cuttings are reported. Apices from seedlings, axillary buds from young lignified branches of mature trees, and axillary buds obtained through in vitro axillary branching from microcuttings isolated onto mature trees were all successfully micrografted on seedling rootstocks. A sterilization procedure for field explants is reported. Propagation via cuttings and via micrografting are discussed with regard to rejuvenation of mature donor trees. 相似文献
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刺五加繁殖生态学研究生殖配置(英文) 总被引：1，自引：0，他引：1
在东北林业大学帽儿山生态站的天然次生林里（４５°２３′～４５°２６′Ｎ，１２７°３６′～１２７°３９′Ｅ）对刺五加的生殖配置进行研究，发现刺五加每年分配给有性繁殖的能量和无性繁殖的能量与植物总能量的百分比分别是年龄的幂函数，只是幂指数不同，ｂ有性＝０．８７４０，小于１；ｂ无性＝２．１９９２，大于１．这种关系表明在样本覆盖的年龄范围内（５～１５年），刺五加分配给无性繁殖的能量逐年递增得较快，分配给有性繁殖的能量逐年递增得较慢．由此可以推测林下刺五加随着林分稳定性增加，逐渐以无性繁殖为主．根据研究结果，建议在天然次生林下对刺五加进行采挖时不要把根茎全部取走，应留下一部分，使其保持天然更新的能力．同时，对根茎需要适当切割，促进芽转化为无性小株，有利于更新 相似文献
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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. 相似文献
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Catherine Ky-Dembele Jules Bayala Antoine Kalinganire Fatoumata Tata Traoré Bréhima Koné Alain Olivier 《Southern Forests》2016,78(3):185-192
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. 相似文献
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采用3种不同的方法对杜松种子进行催芽处理实验,结果表明:相比于混砂催芽方法和温、冷水交替浸种催芽法,采用热水浸种、变温催芽方法处理的种子,播种后出苗时间短,苗齐,其1年生幼苗高生长、地径以及壮苗数量都较高。在育苗上,热水浸种、变温催芽方法要好于其它两种方法。 相似文献