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1.
《Scandinavian Journal of Forest Research》2012,27(4):304-316
Variation in radial increment at different stem heights was compared with stem volume increment and height increment using thinning experiments of Picea abies (L.) Karst. in southern Finland. The magnitude of growth variation was similar on trees from different crown classes and stand densities. However, there was higher autocorrelation in the codominant and intermediate trees and trees on dense plots. The relationship between short-term volume increment and radial increment variation at breast height was not affected by thinnings. While short-term growth variation was similar at different stem heights, some evidence was found for differences in medium-term variation between radial increment at breast height and volume increment. Height increment reacted to unfavourable climatic events later than radial and volume increment. Radial and volume increments were negatively correlated to temperature and positively correlated to precipitation of the current summer. Height increment was positively related to current early summer temperature, but negatively to temperature of the previous summer. 相似文献
2.
Aristotelis C. Papageorgiou Amaryllis Vidalis Oliver Gailing Ioannis Tsiripidis Seraphim Hatziskakis Stefanos Boutsios Spiros Galatsidas Reiner Finkeldey 《European Journal of Forest Research》2008,127(1):81-88
The recent taxonomic classification of beech in Europe considers existence of one species (Fagus sylvatica L.) with two subspecies: F. sylvatica ssp. sylvatica and F. sylvatica ssp. orientalis. Four beech populations growing on the Greek part of the Rodopi Mountains were studied using morphological traits as well
as DNA molecular markers (AFLPs and chloroplast DNA SSR). The aim of the study was to describe the variation patterns of beech
in the Rodopi Mountains and to test the hypothesis of possible introgression between the beech subspecies’ sylvatica and orientalis in this area. Both morphological traits and gene markers revealed a possible influence of F. orientalis on the east side of Rodopi and at the low elevations, while characters resembling F. sylvatica were observed mainly on the western part of the mountains and in higher altitudes. There was a clinal increase of genetic
diversity from the west to the east, reaching a level firstly reported for beech populations. These results can be explained
either by the existence of a main refugial area for beech during the last glaciation or by the occurrence of a recent hybridization
among the subspecies, which were spatially isolated during the last glaciation and came into reproductive contact during their
postglacial remigration. These two scenarios are not necessarily mutually exclusive. 相似文献
3.
Natural black poplar (Populus nigra L.) clones sampled from river courses were tested in the arid southeast region of Turkey, using a randomized complete block field design with four replications. Clones were laid out in row plots of eight ramets each. Height and apical dominance were assessed at age one year; diameter, survival, bole straightness and branchiness were measured at age two years. Clones differed significantly in survival, growth and quality traits. The results showed that promising clones exist in natural populations. Two commercial clones out of four did not grow as fast as the top new selection clones. For bole straightness, three commercial clones had significantly lower grading scores than the top best 14 clones. Principal components analysis indicated that growth, apical dominance and branching are the most important traits distinguishing black poplar clones. Diameter had a moderate correlation (0.34) with bole straightness. Relationships between geographic variables (elevation, latitude and longitude) with growth and stem quality traits were weak. Considerable genetic variation was observed among clones for all the traits. Genetic differences among the clones accounted for 27% (survival, bole straightness) to 39% (height) of the total variance. Broad-sense individual heritability ranged from 0.27 (survival) to 0.37 (apical dominance). Clonal mean heritabilities were higher than individual heritabilities and ranged from 0.60 (survival) to 0.82 (diameter), implying considerable gain could be realized via selective improvement methods. 相似文献
4.
Black locust (Robinia pseudoacacia L.) is one of the most important stand-forming tree species in Hungary and its importance is increasing in many countries.
Black locust plants are commonly produced by two methods, by seed and by root cuttings. Tissue culture propagation can be
considered as a relatively new method. Growing trees from seed is a relatively simple method for reliably producing seedlings
on a large scale under a variety of circumstances. Mechanization of the method is easy and the production cost is relatively
low. Propagation from root cuttings and tissue culture are valuable for reproduction of superior individuals or varieties.
By applying these methods, superior traits of the selected trees can be preserved in the clones. Recent experiments demonstrated
that micropropagated trees could be successfully transplanted into soil, hardened and grown in the field.
Biography: Karoly Redei (1952), male, doctor, deputy director general of Hungarian Forest Research Institute H-1023 Budapest, Frankel
Leó Str. 42 44, HUNGARY.
Responsible editor: Chal Ruihai 相似文献
5.
匈牙利刺槐(Robinia pseudoacacia L.)改良的繁殖方法(英文) 总被引:1,自引:1,他引:1
在匈牙利,匈牙利刺槐(Robinia pseudoacacia L.)是重要的成林树种之一,且该树种的重要性在世界其它国家也日益增加。该树种的生产通常有两种方法:种子和根插条。组织培养对该种来说是一种相对较新的方法。对于在各种环境条件下大规模地生产苗木来说,种子栽培是相对简单的方法,机械化方法比较容易且生产成本相对较低。根插条和组织培养对于优势个体或品种繁殖是有价值的。利用这些方法,所选出的树木的优势品质可以在无性系得以保存。近期实验表明,微繁殖树木可以成功地移植到土壤中,在野外生长。 相似文献
6.
以脐血橙Citrus.Sinensis(L).Osbeck cv. Washington Sangnine果实为试材,用1.0g/L SA对其浸泡30min后6℃恒温贮藏,对照用自来水浸泡30min后6℃恒温贮藏。对贮藏过程中不同时期果肉硬度、总色差、可溶性固形物含量、O2.-产生速率、单位鲜重脯氨酸(Pro)含量、相对电导率、丙二醛(MDA)含量及脂氧合酶(LOX)、超氧化物歧化酶(SOD)和过氧化氢酶(CAT)活性进行了测定。结果表明:SA能有效地延缓脐血橙果实中SOD、CAT活性的降低,抑制果实中LOX活性和MDA含量的增加,降低果皮中超氧阴离子产生速率,提高果皮中脯氨酸含量,并且对提高果实可溶性固形物(TSS)含量、改善果实的色泽、硬度也有明显的效果。 相似文献
7.
Boy J.H.M. Possen Elina OksanenMatti Rousi Hanna RuhanenViivi Ahonen Arja TervahautaJaakko Heinonen Juha HeiskanenSirpa Kärenlampi Elina Vapaavuori 《Forest Ecology and Management》2011,262(8):1387-1399
For northern Europe’s climate, models predict an increase in periods of drought and waterlogging. Knowledge of variation between genotypes of Betula pendula (birch) and Populus tremula (aspen) to drought and excess soil moisture are unavailable but relevant for future development of forest ecosystems. We studied variation between genotypes to soil moisture in birch and aspen with plant material representing naturally regenerated populations and showed differences in acclimation to soil moisture conditions. Genotypes showing most growth and biomass accumulation across treatments maintained most leaf area, high gas exchange and water-use efficiency and grew most root mass but had the lowest root length per unit root dry mass compared to other genotypes. This indicates that these genotypes are more efficient in harvesting water from the soil under adverse conditions. We also showed that birch and aspen employ different strategies to cope with soil moisture conditions, with aspen investing more in perennial parts, while birch efficiently maintains foliar processes. When the expression of some known drought responsive genes was measured, only ACC oxidase was induced by the drought treatment at the beginning of the experiment, while surprisingly LEA5, RD22 and ADH1 did not respond to drought, but were up-regulated in prolonged wet conditions indicating oxidative stress and hypoxia and that these genes are responding to multiple stress factors. We conclude that in plants micro-propagated from naturally regenerated birch and aspen populations, there is variation between genotypes in acclimation efficiency to soil moisture conditions. 相似文献
8.
《Journal of Sustainable Forestry》2013,32(3-4):63-76
Abstract An experiment was conducted in forest college campus, Mettupalayam, India with an objective of studying the influence of microbial inoculants on seedling growth of teak. The fruits were collected from the seed production area in top slip (Tamil Nadu) from 63-year mother trees. The microbial inoculants viz., Azospirillum, Azotobacter, phosphobacteria, AMF, Azospirillum + AMF, Azotobacter+ AMF, phosphobacteria + AMF and an uninoculated control formed the treatments. The inoculants were mixed sand and red soil at 1:1:3 ratio, respectively, for preparing nursery mixture for filling the poly pots. The seeds were sown into the poly pots @ two seeds per pot. The experiment was set up in a randomized Block Design with three replications. Biometric observations on various growth attributes were recorded six months after treatment and also their survival in the main field-tested for one year. Azotobacter gave best performance with respect to shoot length, shoot weight and leaf area and combined inoculation of phosphobacteria and AMF gave higher root length and biomass, dry matter production and fine root weight. The survival was better in seedlings that were inoculated with phosphobacteria and AMF. However, below ground biomass and out planting survival during early phase are critical in any tree species. Hence it is concluded that inoculation of phosphobacteria and AMF conjointly be done for better survival and growth of teak seedlings. 相似文献
9.
Sergio Miguel Vélez-Zambrano Jefferson Bertin Vélez-Olmedo Susana García Bianca S. A. Bonfim Pedro Emilio Cedeño Danilo Pinho 《Forest Pathology》2023,53(5):e12830
Teak is a very important tropical timber in Ecuador. In 2017, teak samples displaying stem canker symptoms were collected in two provinces of Ecuador. From 11 symptomatic trees, 11 isolates resembling a species of Lasiodiplodia were obtained. All isolates obtained induced stem canker on teak plants after artificial inoculation, confirming them as the cause of the observed canker symptoms. Bayesian inference with concatenated sequences of complete ITS and partial TEF-α and β-TUB gene sequences from two representative isolates clustered teak isolates with other sequences of Lasiodiplodia theobromae available in Genbank. This is the first report of L. theobromae causing stem canker on teak plants in Ecuador. 相似文献
10.
《Scandinavian Journal of Forest Research》2012,27(2):117-126
Prunus avium L. is a fast-growing hardwood tree species that has demonstrated good production on both well-drained forest soils and farm land in southern Sweden. Growth rate and breeding value were tested in 101 open-pollinated single-tree progenies of Swedish origin and five German seed sources. After eight growing seasons and two selective thinnings the mean tree height reached 4.7 m. The mean tree height of the progenies varied between 3.3 and 6.1 m. A total rotation period of 50-60 yrs and a dominant height of 20-22 m can be expected. The results indicated great phenotypic variation within progenies and good possibilities for improving production and stem quality by early selective thinning. In terms of height growth and stem straightness the best Swedish progenies were as good as the tested German seed sources. 相似文献
11.
《Forest Ecology and Management》1998,108(3):215-222
Seedling anatomy and cross sectional discs of 8- and 12-year-old (juvenile) teak trees were examined for tree ring analysis and determination of environmental factors responsible for false ring formation in teak. Based on the anatomy and location within the true annual rings, four types of false rings were identified. The results from both cross-dating of plantation grown trees and controlled experiments, including induced drought, showed that rainfall during dry period, drought during active growing season, (container) polybag/field transplantation of seedlings and juvenility are the important causative factors of frequent false rings in teak. No definite relationship could be established between insect defoliation and the incidence of false rings. False ring formation in teak appears to be mainly a resultant feature of tree ring responses to different environmental and physical factors. 相似文献
12.
Citrus gummosis incidence and role of ants (Lasius grandis) and snails (Helix aspersa) as vectors of the disease in Tunisia
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N. Benfradj A. M. Vettraino A. Tomassini N. Bruni A. Vannini N. Boughalleb‐M'Hamdi 《Forest Pathology》2018,48(3)
Surveys were conducted between November 2011 and December 2013 to determine the distribution and the incidence of citrus gummosis in Tunisia. Forty‐two citrus orchards in three different citrus areas were surveyed. Symptoms of gummosis were observed in 59.52% of the orchards. The highest incidence was observed in the Cap Bon area. The involvement of some invertebrates in the epidemiology of citrus gummosis was also confirmed. Species of ants (Lasius grandis), snails (Helix aspersa and Rumina decollata) and worms (Armadillidium vulgare) collected from 2012 until 2014 were tested for the presence of Oomycetes. Phytophthora nicotianae and Phytopythium vexans were isolated from the bodies of Lasius grandis and also from bodies and faeces of Helix aspersa. However, no Oomycetes were isolated from the bodies of Rumina decollata and Armadillidium vulgare. In vitro assays, Helix aspersa was fed with P. nicotianae‐ and Ph. vexans‐infected citrus bark showed the existence of those pathogens in 79.1% of the faeces of snails. In vivo assays, snails and ants were able to transmit the pathogens vertically from the base of potted 2‐year‐old trees citrus variety Clementine Mandarin cv. Hernandina, to other parts of the tree. 相似文献
13.
14.
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 相似文献
15.
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 excise... 相似文献
16.
《Scandinavian Journal of Forest Research》2012,27(1-4):293-302
Twenty sets, each consisting of a tall, a medium, and a small plant, were selected from a 2 by 2‐year‐old nursery crop. Selection differential was measured. Cutting propagation was undertaken and the subsequent clones were tested in a field experiment. Differences between groups at age 1, 2, 3, 6, 8, and 10 were calculated, and ortet/ramet regressions and age‐to‐age correlations were conducted. Selection of the tall plants gave a response of approximately 17% at age 10. Accumulated genetic gain at this age by a specified stepwise selection procedure is estimated to 36%. Step one is the early selection in the nursery, step two is a later selection amongst the early selected clones and performed after 7 years’ field testing. Ageing of clones, selection for other traits and application of the clones over a variety of sites will reduce these gains. 相似文献
17.
Natural variation in seed characteristics of eastern white pine (Pinus strobus L.) trees and its relationship with the size, form, and crown class of parent trees was examined in second-growth, white
pine mixedwood stands in Ontario. Cones were collected prior to and following partial harvesting of two stands during 2 years
of above-average seed production. Fully enlarged seed extracted from mature cones was X-rayed to determine seed yield per
cone, the percentage of sound, partially filled, and empty seed, and the sound seed mass for each tree. Variation in seed
yield per cone, the proportion of sound, partially filled, and empty seed, and seed mass was much greater among individuals
than between stands or seed years. The strength and significance of the relationship of seed mass with sound seed yield differed
with stand and seed year. In uncut stands, seed mass was higher for trees with dominant crown class, larger live crown ratios,
and smaller height to diameter ratios, suggesting tree vigour and microsite quality influence seed mass. Proportion of partially
filled seeds was significantly reduced in both stands in the second year likely due to increased growing degree days during
female gametophyte development. The implications of these results to natural and artificial regeneration of white pine are
discussed. 相似文献
18.
Natural regeneration of stone pine (Pinus pinea L.) stands in the Central Range of Spain can be difficult to attain. The success of this regeneration is affected by factors
such as the total amount of seed available, the short dispersal ability of the pinyon, the conditions required for germination,
specific problems associated with the establishment, early survival of the seedlings due to severe summer heat and drought,
competition for water and mineral resources and grazing damage. This study focuses on seed availability. The amount of available
seeds depends on the number and size of the cones and the number of viable pinyons within the cones. In stone pine stands,
both variables show great year to year variability. Both cone and seed production, for a given year, are also conditioned
by the vigour and health of the tree, its size, the condition and attributes of the stand and the loss of seed through pests
or predation. In this study, the main factors which influence cone and pinyon production are identified and a multivariate
model to predict annual cone and viable seed production is developed. To consider the correlation among observations coming
from the same tree, stand or year, random components are included in the model. The multivariate random structure allows for
future calibration of the model for a given year from a small additional sample of observations. It is important to know the
total amount of viable seed produced in a stand for a given year since regeneration cuttings for Stone pine should be concentrated
in high crop years. 相似文献
19.
Multiple shoots of high quality were produced in vitro from nodal expiants of Tectona grandis. An average of about 4 shoots/uninodal expiant was obtained within 4 weeks of culture on Murashige and Skoog’s (mMS) medium modified by 50% reduction in NH4NO3 concentration, supplemented with benzylaminopurine (1.5 mg L?1); indole-3-butyric acid (0.01 mg L?1) and gibberellic acid (0.1 mg L?1). The latter was applied both in the medium and by soaking the nodal segments for 10 s. in a gibberellic acid solution of 100 mg L?1. Hundred percent of shoots rooted cultured on modified MS medium containing IBA (0.5 mg L?1) and putrescine (160 mg L?1). Putrescine promoted both strong and highly ramified roots and fast growing shoots during the rooting phase, conditioning the plantlets for a good survival and quality. Plantlets were transferred to jiffy pots for a short acclimatization stage in greenhouse where they survived at 100%. This highly reproducible procedure can be adopted for large scale teak propagation. 相似文献
20.
Masato Ito 《Journal of Forest Research》2009,14(4):240-244
I describe variation in leaf morphology of Quercus crispula and Quercus dentata assemblages within and among their contact zones. Such relationships provide a relatively fast and accurate method for detecting
hybridization. Using discriminant function (DF) analysis based on leaf characteristics, I was able to differentiate between
these two species in pure zones. In three of five contact zones, the DF scores showed broad, continuous distributions with
three or more peaks. The trees showing intermediate leaf morphology are considered to be hybrids. In the other two contact
zones, the DF scores showed distinct bimodal distributions, suggesting that Q. crispula and Q. dentata rarely hybridize in these sites. Thus, the method described in this study should be effective for detecting probable hybridization
between these two species in contact zones, and the relative frequency of hybridization among contact zones. However, there
was likely to be intraspecific variation of Q. crispula between geographic ranges, restricting interpretations to patterns occurring within sites or limited geographic ranges. 相似文献