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1.
《Journal of Sustainable Forestry》2013,32(1-2):187-201
Abstract We investigated how the locations of conspecific fruiting trees, other fruiting species, and canopy gaps affected spatial patterns of bird-dispersed seed rain for a common ornithochorous tree: Daphniphyllum macropodum.In a mature evergreen broad-leaved forest in southwestern Japan, seed rain was monitored with seed traps in a 1.2 ha plot on a site with a generally closed canopy. Many of the bird-dispersed seeds of D. macropodumwere concentrated near the conspecific fruiting trees, while other seeds were scatter-dispersed. The spatial distribution of scatter-dispersed seeds was independent of the distance from conspecific fruiting trees. The scatter-dispersed seed rain of D. macropodumwas biased by abundant and widely distributed fruiting trees of Cleyerajaponica.Other rare fruiting species and canopy gaps had no clear effect on the seed rain of D. macropodum.Results show that the spatial pattern of bird-dispersed seed rain in this forest is affected by the location of fruiting trees of the same and different ornithochorous species rather than by canopy gaps. 相似文献
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The cutting propagation technique ofPicea koraiensis was carried under automatic spraying of total sunlight by adopting the same year epicormic branches from different trees
with different age treated by different hormones in different concentration and time and the orthogonal and randomized block
was designed. The results were as follows: (l)The rooting rate of the cutting reached at least 87 percent, when the cuttings
were from the seed tree with the age below 25 years old and the cuts of the cuttings base were in vertical angle and on the
fine sand medium. (2) The sequence of effective factors affecting the rooting rate were the style of cut, the age of seed
tree and the type of medium. (3) There are significant differences of rooting rate among different clones. 相似文献
4.
Pollen dispersal was estimated in two test plots in a hinoki (Chamaecyparis obtusa) seed orchard using a chloroplast DNA marker, the spacer region between thetrnD andtrnY genes, and SSCP (single strand conformation polymorphism). In Plot 1, 2,020 seeds from 40 trees within 30 m of the marker
tree were analyzed using the PCR-SSCP method. In Plot 2, 1,850 seeds from 37 trees were analyzed in the same manner. The results
revealed that the maximum pollen dispersal distance in the two plots exceeded 25 m. Pollen dispersal appeared to be inversely
proportional to the distance from the marker tree. The effective pollen dispersal was suggested to be less than about 20 m
in a mature hinoki seed orchard. Adjacent trees had an excessive influence when the pollen density was increased by artificial
flower stimulation. Therefore, it was suggested that seed production better resembles ideal random mating when carried out
as naturally as possible. In conclusion, the SSCP chloroplast DNA marker was a useful tool for amassing basic information
on pollen management in seed orchards of coniferous species. 相似文献
5.
A. Zamani R. Sturrock A. K. M. Ekramoddoullah S. B. Wiseman M. Griffith 《Forest Pathology》2003,33(5):299-316
Extracellular proteins were extracted from Phellinus weirii infected Douglas‐fir (Pseudotsuga menziesii var. menziesii) roots and needles to examine endochitinase activity. Chitinases have been associated with the plant's defence response against fungal attack because they hydrolyse chitin, a structural component of fungal cell walls. Protein separation using sodium dodecyl sulphate‐polyacrylamide gel electrophoresis (SDS‐PAGE) followed by Western immunoblot analysis using a polyclonal antibody specific to an endochitinase‐like protein (ECP) resulted in the detection of up to three polypeptides between 27 and 30 kDa in size. Two‐dimensional gel electrophoresis (2‐D PAGE) followed by Western immunoblot analysis revealed that the apoplastic fluid contained multiple ECP isoforms with isoelectric points (pIs) ranging from 5.3 to 5.8 and molecular masses of 27–30 kDa. Chitinase activity in needle and root tissues was measured spectrophotometrically using a colorimetric assay. A gel overlay technique using glycol chitin as a substrate for endochitinase was applied to confirm that the ECP antibody detected an enzymatically active protein. The apoplastic fluid collected from P. weirii‐infected winter Douglas‐fir needles showed anti‐freeze activity and seasonal analysis of needle tissue showed some evidence of ECP accumulation in winter months. ECP was distributed systemically throughout the tree. Increased levels of endochitinase activity in the region of P. weirii infection supports a physiological role for ECP in the plant defence response. 相似文献
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Genetic male sterility is a useful trait in plant breeding, especially in angiosperm crops such as corn, onion and carrot.
We found a male sterile sugi (Cryptomeria japonica D. Don) tree in Toyama, Japan. Pollen of sugi is one of the major causes of pollinosis in Japan. We carried out this research
in an attempt to make clear the characteristics and inheritance of this male sterility. Microsporogenesis of the male sterile
tree proceeded meiosis, however, the microspores collapsed after they were separated from pollen tetrads in locules, resulting
in complete male sterility. Most likely, ethylene evolution was responsible for male sterility expression. Full seed setting
in the male sterile tree indicated normal macrosporogenesis. Seeds obtained from crossing between male sterile and normal
lines showed relatively high level of germination and their seedlings grew vigorously. The somatic chromosome numbers of 241
germinated seeds, derived from the male sterile tree, were mostly 22, euploid. These results indicated that male sterile tree
was different from other similar previously reported trees with low pollen fertility, resulting from triploid or trisomics.
Probably, male sterility in sugi is either nuclear genetic male sterility or cytoplasmic male sterility.
The study was partially supported by Program for Promotion of Basic Research Actives for Innovative Biosciences. 相似文献
8.
Realized genetic gains brought by the first-generation tree improvement of Acacia mangium were evaluated by analyzing the 1-year growth performance of growth (height, dbh) and form (stem straightness, multi-stem) traits using data collected from three second-generation orchards: groups B, C, and D. Each orchard was composed of improved families derived from open-pollinated seed of plus trees selected from the first-generation seed orchards and newly added unimproved families collected from the same geographic region. The number of improved families and that of the unimproved in each orchard were 31 and 23 for group B, 28 and 39 for group C, and 24 and 30 for group D. Gains were calculated as percentage increase of improved families over unimproved ones. Improved families performed better than unimproved ones in 11 out of 12 comparison cases: four traits each in the three orchards. Averages of the realized genetic gain across the three seedling seed orchards were 3.1%, 5.2%, 4.3%, and 0.5% for height, dbh, stem straightness, and multi-stem, respectively. Except for multi-stem, the performances of improved families were significantly better than those of unimproved families in all the three orchards for dbh and in two out of three orchards for height and stem straightness. 相似文献
9.
Pongamia pinnata an oil yielding leguminous tree is an economically important plant due to its multifunctional characteristics. The objective
of the present study was to investigate the electrophoretic spectra sodium dodecyl sulfate polyacrylamide gel electrophoresis
(SDS-PAGE) of total soluble seed proteins under reduced conditions (5 mM β-mercaptoethanol) in immatured [135 days after flowering
(DAF)] and matured stages (350 DAF) for 10 tagged candidate plus trees (CPTs) of P. pinnata from North Guwahati. SDS-PAGE analysis revealed presence of ~15–20 unique polypeptide fragments of molecular size ranging
from 14 to 150 kDa in both stages of seed development but no variations was observed at a particular stage among 10 CPTs.
However, polypeptide banding pattern of immatured and fully ripened matured seeds showed differences in expression pattern
of three main polypeptide bands (MW 50, 18 and 14 kDa) for all the 10 CPTs studied. Globulins may be considered to be the
main seed storage proteins in Pongamia that includes legumins and vicilins. 相似文献
10.
Non-destructive methods for determining the biomass and leaf area of individual trees throughout their growing cycle are an
essential tool in agroforestry research, but must be capable of providing reliable estimates despite the influence that management
strategies such as pruning may have on tree form. In the present study, allometric methods involving measurements of the diameter
of all branches provided reliable estimates of canopy leaf area and biomass for grevillea trees (Grevillea robusta A. Cunn.; Proteaceae) grown as poles, but proved unsuitable for routine measurements because of their time-consuming nature.
An alternative, less laborious method based on measurements of trunk cross-sectional area immediately below the first branch
of the canopy provided satisfactory allometric estimates of leaf area and canopy biomass. Trunk biomass was determined from
measurements of tree height and diameter at breast height using established methodology based on the assumption that trunk
volume may be calculated using a quadratic paraboloid model; biomass was determined as the product of trunk volume and the
specific gravity of the wood. The theoretical basis, development and validation of allometric methods for estimating tree
growth are discussed and their wider applicability to other agroforestry systems is assessed.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
11.
Since 2008, severe and widespread tree decline and mortality has been observed at the main growing Quercus ilex L. (holm oak) forest on Caprera Island, Italy. To clarify the symptomatology and aetiology of this phenomenon, field surveys and isolations from symptomatic trees were carried out in summer 2010. Affected trees exhibited crown thinning, branch dieback, sunken cankers, epicormic shoots, exudates on branches and trunk, root losses and sudden death symptoms. Four fungal species belonging to Botryosphaeriaceae family, namely Botryosphaeria dothidea, Diplodia corticola, D. seriata and Neofusicoccum parvum, were isolated from cankers on trunk and branches, whereas three species of Phytophthora, namely P. cinnamomi, P. cryptogea and P. gonapodyides, were isolated from fine roots and rhizosphere soil samples. Isolates were identified using both morphological analysis and DNA‐based techniques. Pathogenicity trials on holm oak seedlings showed that all the isolated species are pathogenic. D. corticola proved to be the most aggressive species. Our results provide the first evidence for a combined involvement of D. corticola and P. cinnamomi in the aetiology of holm oak decline in Italy and suggest that these pathogens are not only important contributing factors in the onset of long‐term tree decline, but also may cause the rapid devastation of extensive oak ecosystems. 相似文献
12.
Ramón Perea Alfonso San Miguel María Martínez-Jauregui María Valbuena-Carabaña Luis Gil 《European Journal of Forest Research》2012,131(3):623-631
We examine whether different guilds of foragers remove seeds differentially according to seed quality (seed size and insect
infestation) and seed location (habitat and microhabitat) in a mixed oak-beech forest. Video recordings indicated that the
wood mouse (Apodemus sylvaticus) was first to encounter seeds. Foragers preferred acorns to beechnuts, large to small size and sound to infested. Nevertheless,
infested seeds were removed by rodents even when sound seeds were present. Seeds that were not preferred by scatter-hoarding
rodents remained longer on the ground and were more vulnerable to predation and desiccation (4% moisture loss per day). However,
seeds that were removed by scatter-hoarders were moved away from their mother trees (96%) and cached individually (32%), increasing
their moisture content (3% per day). Buried seeds, simulating scatter-hoarding behavior, experienced only a 17% removal after
4 months. Seed removal differences among habitats were not due to habitat attributes but to the spatial distribution of rodent-preferred
microhabitats. Thus, a significant lower seed removal was observed under the tree canopy with no shrubs. However, seed removal
in forest gaps with deadwood cover was not significantly different from the preferred microhabitat (under shrub cover). In
pure beech forests, seed removal by rodents only occurred under Ilex aquifolium (the only perennial cover) and under woody debris. This study concludes that seed quality and seed location determine the
contribution of different removers (predators vs. dispersers), their seed selection and their removal speed, leading to different
seed fates which will eventually affect tree regeneration. 相似文献
13.
Density-dependent selfing and its effects on seed performance in a tropical canopy tree species, Shorea acuminata (Dipterocarpaceae) 总被引:1,自引:0,他引:1
Yoko Naito Mamoru Kanzaki Hiroyoshi Iwata Kyoko Obayashi Soon Leong Lee Norwati Muhammad Toshinori Okuda Yoshihiko Tsumura 《Forest Ecology and Management》2008,256(3):375-383
In the conservation and management practices of natural forests, sound reproduction and regeneration form the basis of the maintenance and viability of the tree populations. To obtain and serve biological information for sustainable forest management, we investigated reproductive biology and inbreeding depression in seeds of an important dipterocarp tree species, Shorea acuminata (Dipterocarpaceae), by both field and laboratory experiments. Results of parental analysis of immature and mature seeds showed that selfing rates varied greatly, from 7.6 to 88.4% among eight mother trees, and the mean overall selfing rate was 38.3%. Observed outcrossing events within a 40-ha study plot were predominantly (76.5%) short-distance events with a mating distance (md) ≤ 100 m. Since the selfing rate sharply decreased with increase in the number of flowering conspecifics (i.e., individuals of the same species) within a 100-m radius from the mother trees, the local density of flowering conspecifics appears to be the key factor determining the outcrossing rate in S. acuminata. However, the extremely high selfing rate (88.4%) observed for one tree could not be simply explained by the low local density of flowering conspecifics. Instead, differences in its flowering phenology (its flowering peaked ca. a week earlier than most of the other examined individuals) may have severely limited its receipt of pollen from other conspecifics, and thus promoted selfing. Since there were no significant differences in the proportion of selfed progeny between immature and mature seed stages, there was no evidence of selective abortion of selfed seeds during seed development. However, the seed mass of outcrossed progeny was heavier than that of selfed progeny, and heavier seeds showed higher success rates at germination and seedling establishment. These results suggest that inbreeding depression resulted in reductions in seed mass and may reduce the fitness of selfed seeds in S. acuminata. In addition, the outcrossing rate of S. acuminata was more sensitive to low local conspecific flowering-tree densities than that of a sympatric bee-pollinated dipterocarp species with greater pollination distances. These results suggest that the management of local adult-tree densities is important for avoiding selfing and inbreeding depression in future generations, especially in a species like S. acuminata with predominantly short-distance pollination. 相似文献
14.
The success of direct seeding, as a low-cost approach to forest restoration, varies with tree species and seed characteristics.
A system to predict which tree species are likely to be suitable for direct seeding would therefore be useful for improving
forest restoration projects. Therefore, this study aimed to determine the effects of seed traits on the success of direct
seeding to restore tropical forest in southern Thailand. Seeds of 19 indigenous lowland tropical forest tree species were
collected, from both the east and west sides of the Thailand peninsular and the following parameters measured: seed size,
shape, coat thickness and moisture content. Field trials were established to determine seed germination rates and to calculate
a “direct seeding suitability score” for each species, which combined seedling establishment and growth rates. Seed size,
shape and moisture content were associated with germination percentage. Species with higher seedling survival tended to have
large or intermediate-sized seeds, round or oval seeds and seeds with low or medium moisture content. Only seed coat thickness
was significantly correlated with the suitability score (r = 0.65, p < 0.01). Seed coat thickness >0.4 mm coincided with higher rank suitability score. These conditions successfully predicted
the success or failure of direct seeding for 15 out of 19 species tested. Eight tree species are recommended as suitable for
restoring lowland evergreen forest ecosystems in southern Thailand, by direct seeding. 相似文献
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《Scandinavian Journal of Forest Research》2012,27(4):290-291
Abstract In 2001 large areas of Pinus sylvestris L. stands in Sweden were attacked by Gremmeniella abietina (Lagerb.) Morelet. The resultant damage was assessed in five genetic field trials and one clonal seed orchard, with the aims of quantifying the genetic variation in tree responses to G. abietina, studying the genetic relationship between G. abietina susceptibility and growth traits, and examining the implications of the results for P. sylvestris breeding. A comparison of G. abietina damage between plus-tree progenies and seed stand check-lots in each of four tree classes (dominant, co-dominant, subordinated and suppressed) found no significant differences except in the suppressed tree class, where plus-tree progenies were damaged less severely than trees from the seed stands. Narrow- and broad-sense heritability for G. abietina damage traits were in the range 0.22–0.42. Genetic correlations between G. abietina damage and growth traits were weak and not significantly different from zero. The results imply that selection for growth capacity in P. sylvestris breeding programmes using plus-tree selection or field progeny tests does not increase susceptibility to G. abietina. In addition, there is scope for selecting genotypes with increased resistance if this is required in the future. 相似文献
17.
作为松材线虫病(Bursaphelenchus xylophilus)的最重要传播媒介,松褐天牛已成为控制松材线虫病的重点。明确松褐天牛各虫态在不同地区寄主树干上的分布,对因地适宜地释放天敌昆虫有着重要意义。为此,本研究通过解剖受害马尾松,结合林间调查,系统地研究了松褐天牛产卵刻槽、幼虫和蛹在马尾松树干上的分布规律。结果表明:松褐天牛产卵刻槽主要分布在树干的2.5 6.5 m范围内,刻槽数量与树干高度和胸径显著相关;松褐天牛幼虫数量与树干胸径关系不显著;多数蛹室位于侵入孔正上方,少数蛹室位于侵入孔下方,两种蛹室数量差异显著;两种蛹室与侵入孔中心的平均距离分别为3.93 cm和4.39 cm,两者之间差异不显著;并建立了松褐天牛幼虫在马尾松树干上的垂直分布模式图。本研究表明了松褐天牛种群密度与寄主树木大小的关系,为释放天敌进行生物防治提供了基础。 相似文献
18.
Motoshi Hiratsuka Takeshi Toma Nina Mindawati Ika Heriansyah Yasushi Morikawa 《Journal of Forest Research》2005,10(6):487-491
Biomass of a mature man-made forest in West Java, Indonesia, was estimated to evaluate the carbon sequestration potential
of plantation forest in the humid tropics. Twenty plots, each 0.25 ha in area and containing one to six planted species over
40 years of age and with closed canopies, were selected. Trunk dry mass was estimated from trunk diameter, tree height, and
bulk density. Maximum trunk diameter (122 cm) was observed in a 46-year-old Khaya grandifoliola C. DC. tree, and the tallest tree (51 m) was a 46-year-old Shorea selanica (DC.) Blume. The largest trunk biomass (911 Mg ha−1) was achieved in the plot composed of two Khaya spp. Among the plots composed of indigeneous Dipterocarpaceae species, the largest trunk biomass was 635 Mg ha−1. These trunk biomasses were larger than those reported from primary rainforests in Southeast Asia (e.g., 403 Mg ha−1 in East Kalimantan, 522 and 368 Mg ha−1 in Peninsular Malaysia). The large biomass in this forest suggests that, given favorable conditions, man-made forests can
accumulate the quantities of atmospheric carbon that were lost by the logging of primary forests in the humid tropics. 相似文献
19.
S. De Smedt K. Alaerts A. M. Kouyaté P. Van Damme G. Potters R. Samson 《Agroforestry Systems》2011,82(1):87-97
We analyzed the phenotypic variation of baobab (Adansonia digitata L.) fruits from Mali to define the domestication potential of this species. 269 trees, selected from 10 provenances distributed
along a rainfall gradient, were characterized. Five fruits were sampled from each tree. Total individual fruit weight was
partitioned into shell, pulp, and seed weight. Ratios were calculated between pulp + seed and total weight, and between pulp
and seed weight. For all the measured fruit traits, we detected significant differences between provenances, as well as between
trees from the same provenance. Assuming that the measured traits are under genetic control, the latter facts indicate that
there are considerable opportunities for tree selection on a local scale. However, candidate plus trees with specific properties,
e.g., extremely high pulp or seed weight, were found only in some locations. Mean pulp yield per fruit might be considerably
increased by selecting the 5% trees with the highest pulp weight (mean: 45 ± 1 g, best 5%: >100 g). The same might be true
for seed production (mean: 71 ± 2 g, best 5%: >150 g). Also the ratio between pulp and seed weight can be an important fruit
characteristic for selection: in fruits with a low ratio, relatively more pulp sticks to the seeds when separating the two
fruit parts by grinding, and thus more pulp will be lost for further processing. We identified several trees with a high pulp
weight combined with a high ratio between pulp and seed weight. It is concluded that there is considerable phenotypic variability
in traits of baobab fruit in Mali, offering opportunities for cultivar selection. 相似文献
20.
As a tree management tool, three treatments of crown pruning (total-pruning, half-pruning and no-pruning) were applied to
Vitellaria paradoxa (karité) and Parkia biglobosa (néré) in agroforestry parkland systems in Burkina Faso. The area under each tree was divided into four concentric tree influence
zones (Zones A: up to 2 m from the tree trunk, B: up to half of the radius of the tree crown, C: up to the edge of the tree
crown and D: up to 2 m away from the edge of the tree crown). Millet production under these zones and outside was assessed
during two cropping seasons over the study period of three years and the results showed that tree crown pruning had significant
effect on millet production and the highest millet grain yield and total dry matter were produced under total-pruned trees
(507 ± 49 and 2033 ± 236 kg ha−1 year−1, respectively). Light transmission, transpiration and soil nutrient status under the trees were also analysed in relation
to millet production. The results of the analysis showed that total-pruned trees gave the highest millet production due to
the reduction by crown pruning of the effects of large tree crowns on PAR transmission below crowns and rates of transpiration
by trees. Soil was more fertile closer to the tree trunks than outside tree crowns. This may also be one of the reasons why
millet overall performed better under Zone B than outside tree crowns. The higher production of millet under Zone B than under
Zone A, the zone closer to the tree trunk, may be due to lower light intensity and more intense competition for water between
trees and crops under Zone A. It was concluded that at least in the short term millet production could be improved by crown
pruning of both karité and néré, but long term effects may depend on the ability of the trees to maintain the amelioration
of soil fertility and on how quickly the trees recover from pruning.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献