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1.
The optimum lifetime of Picea abies seed orchards in Sweden was calculated using a model which considers changes in seed yield over time, annual progress of genetic
gain, establishment, management and seed costs, and both the monetary and genetic value of the seeds produced. The longer
the seed orchard is active, the more genetically outdated the produced seeds will become, and thus their value will decline
with time. A main scenario was constructed using the best available estimates for Swedish Norway spruce and was compared to
various alternatives reflecting likely variations. The optimal lifetimes in all of these scenarios was in the order of 40 years.
Sensitivity analyses showed that use of orchards for slightly more or less than their optimal lifetimes does not lead to large
losses. A more effective tree breeding program could slightly reduce the optimal lifetimes. The optimal lifetime depends strongly
on the relationship between monetary value and genetic gain. Thus, in cases where genetic progress is sufficiently rapid,
the optimal lifetime may be less than 30 years. 相似文献
2.
Cone and seed characters were observed on top, middle and bottom portions of tree crown in 3 ramets/clone in three Turkish
Pinus sylvestris seed orchards. Broad sense heritability (clonal repeatability), and correlations among characters were estimated. Around
one quarter of the seed production occurred in the top portion, half in the middle and one quarter in the bottom portion of
the crown for all orchards. The percentage of filled seeds varied little with the crown position, indicating more or less
similar levels of selfing in the bottom of the crown as in the top. The seed weight was typically 11 mg. Differences were
found for studied cone and seed characters among orchards and crown positions. Variation among grafts within clone was higher
than among clones for most characters. The heritability was on average below 0.5 (e.g., cone diameter, number of filled seed
per cone) and rarely rose above that (e.g., cone form, length/diameter; percentage of filled seed) for any individual characters.
The coefficient of variation within clones was often higher than among clones. Thus, non-genetic factors seem often more important
for the variation in performance of grafts than their genetic constitution. Cone form (length/diameter) was the character
where the clone influence was the strongest. Cone number and cone dry weight showed significant correlations with seed characters
(numbers of total and filled seed, percentage and weight of filled seeds). Significant correlation was found between seed
characters. 相似文献
3.
The problem of salinized soils has become one of the most serious constraints to agricultural and forest productivity. With the purpose of enhancing salt stress tolerance of Populus tomentosa, we transformed this tree species with spermidine synthase (SPDS) genes derived from an apple by an Agrobacterium-mediated method. Four transgenic clones were confu'med by PCR and Southern blot analysis. As well, the expression of introduced SPDS genes was analyzed by real-time quantitative PCR. 相似文献
4.
Akram Taghizadeh Saroukolai Saeid Moharramipour Mohammad Hadi Meshkatalsadat 《Journal of pest science》2010,83(1):3-8
Red flour beetle Tribolium castaneum (Herbst) and rice weevil Sitophilus oryzae (L.) are considered to be the major insect pests in storage. Essential oils from aromatic plants are recognized as proper
alternatives to fumigants. Thymus persicus (Ronniger ex Rech. f.) is one of these plants that have medicinal properties and is indigenous to Iran. The essential oil
was obtained from aerial parts of the plant and analyzed by GC and GC–MS. Carvacrol (44.69%) and thymol (11.05%) were the
major constituents of the oil extracted. In this experiment, fumigant toxicity of the essential oil was studied against T. castaneum, S. oryzae at 27 ± 1°C and 60 ± 5% RH in dark condition. The adult insects were exposed to the concentrations of 51.9, 111.1, 207.4
and 370.4 μl/l air to estimate median lethal time (LT50) values. The fumigant toxicity was increased in response to increased essential oil concentrations. The LT50 values at the lowest and the highest concentrations tested were ranged from 28.09 to 13.47 h for T. castaneum, and 3.86 to 2.30 h for S. oryzae. It was found that S. oryzae adults were much more susceptible to the oil than T. castaneum. After 24 h of exposure, the LC50 values (95% fiducial limit) for T. castaneum and S. oryzae were estimated to be 236.9 (186.27–292.81) and 3.34 (2.62–4.28) μl/l air, respectively. These results suggest that T. persicus essential oil merits further study as potential fumigant for the management of these stored-product insects. 相似文献
5.
For improving seed germination of Prosopis koelziana and Prosopis juliflora, different treatments of seeds were conducted, including scarification with sulfuric acid 98% for 10 and 15 min, sandy paper,
hot water for 5 and 10 min, potasium nitrate 0.1%, gibberellic acid at 250 mg·L−1 and 500 mg·L−1 and combinational treatment of scarification with gibberellic acid of 250 mg·L−1 and 500 mg·L−1. The results show that scarifications with sandy paper and sulfuric acids 98% were the most effective treatments on breaking
seed dormancy and seed germination induction. Scarification with sulfuric acid 98% for 15 min was the best treatment. According
to the positive effect of scarification and lack of reaction of seeds against KNO3 and gibberellic acid, the kind of seed dormancy was determined as exogenous. 相似文献
6.
A two-year study was conducted evaluating Puffer® aerosol dispensers (Suterra LLC, Bend, OR, USA) for mating disruption of codling moth, Cydia pomonella (L.), and the oriental fruit moth, Grapholita molesta (Busck). The Puffer® dispenser consists of a pressurized metal canister loaded with pheromone active ingredients dissolved in solvent and housed within a circuit-controlled, plastic dispensing cabinet programmed to release an aerosol spray of pheromone at regular intervals. Puffers® were deployed at the label-recommended rate of 2.5 ha?1 and released ca. 5–10 mg of pheromone (depending on treatment) per 15 min during a 12-h cycle beginning each day at 15:00 h for the duration of the season. In 2005, commercially-managed apple plots (3.2–4.9 ha) were treated with Puffers® releasing both species’ pheromone simultaneously (dual-species) or with twice the number of adjacently-deployed Puffers® (4–6 m apart) releasing each individual species’ pheromones (single-species), while maintaining comparable overall release rates of pheromone between these two treatments. Plots 100 m away and not treated with pheromone served as the control. Disruption of male C. pomonella and G. molesta orientation to pheromone-baited traps was 46–75 and 91–98%, respectively, in Puffer®-treated plots compared with untreated controls. There was no statistical difference in moth disruption between plots treated with dual-species and single-species Puffers®. Fruit injury was not statistically different between Puffer®-treated plots and control plots not receiving pheromone. In 2006, disruption of male moth orientation to traps was 24–26 and 84–97% in Puffer®-treated plots (2.9–5.7 ha) for C. pomonella and G. molesta, respectively, compared with untreated controls. During this season, fruit injury was lower in pheromone-treated plots compared with untreated controls at mid-season, but not at pre-harvest. Combining the pheromone of both species into single Puffer® units did not decrease efficacy of disruption compared with deploying twice as many Puffers® releasing a similar amount of each individual species’ pheromone suggesting that multi-species disruption using Puffers® is a viable option. However, we conclude that the efficacy of disruption attained with low-densities (2.5 ha?1) of Puffers® at the moth densities recorded in this study is insufficient for effective control of C. pomonella without input of companion insecticides. 相似文献
7.
Burcu Çengel Yasemin Tayanç Gaye Kandemir Ercan Velioglu Murat Alan Zeki Kaya 《New Forests》2012,43(3):303-317
To test how efficiently plantations and seed orchards captured genetic diversity from natural Anatolian black pine (Pinus nigra Arnold subspecies pallasiana Holmboe) seed stands, seed sources were chosen from 3 different categories (seed stands (SS), seed orchards (SO) and plantations
(P)) comprising 4 different breeding zones of the species in Turkey. Twenty-five trees (mother trees) were selected from each
SS, SO and P seed sources and were screened with 11 Random Amplified Polymorphic DNA (RAPD) markers. Estimated genetic diversity
parameters were found to be generally high in all Anatolian black pine seed sources and the majority of genetic diversity
is contained within seed sources (94%). No significant difference in genetic diversity parameters (numbers of effective alleles,
% of polymorphic loci and heterozygosity) among seed source categories was found, except for a slight increase in observed
heterozygosities in seed orchards. For all seed source categories, observed heterozygosity values were higher (Ho = 0.49 for SS, 0.55 for SO and 0.49 for P) than expected ones (He = 0.40 for SS, 0.39 for SO and 0.38 for P) indicating the excess of heterozygotes. In general, genetic diversity in seed
stands has been transferred successfully into seed orchards and plantations. However, the use of seeds from seed orchards
can increase the amount of genetic diversity in plantations further. The study also demonstrated that number of plus-tree
clones (25–38) used in the establishment of seed orchards was adequate to capture the high level of diversity from natural
stands. 相似文献
8.
This study evaluated oxalic acid accumulation and bioremediation of chromated copper arsenate (CCA)-treated wood by three brown-rot fungi Fomitopsis palustris, Coniophora puteana, and Laetiporus sulphureus. The fungi were first cultivated in a fermentation broth to accumulate oxalic acid. Bioremediation of CCA-treated wood was then carried out by leaching of heavy metals with oxalic acid over a 10-day fermentation period. Higher amounts of oxalic acid were produced by F. palustris and L. sulphureus compared with C. puteana. After 10-day fermentation, oxalic acid accumulation reached 4.2 g/l and 3.2 g/l for these fungi, respectively. Fomitopsis palustris and L. sulphureus exposed to CCA-treated sawdust for 10 days showed a decrease in arsenic of 100% and 85%, respectively; however, C. puteana remediation removed only 18% arsenic from CCA-treated sawdust. Likewise, chromium removal in F. palustris and L. sulphureus remediation processes was higher than those for C. puteana. This was attributed to low oxalic acid accumulation. These results suggest that F. palustris and L. sulphureus remediation processes can remove inorganic metal compounds via oxalic acid production by increasing the acidity of the substrate and increasing the solubility of the metals.An erratum to this article can be found at 相似文献
9.
Rumi Kaida Tomomi Kaku Kei’ichi Baba Masafumi Oyadomari Takashi Watanabe Sri Hartati Enny Sudarmonowati Takahisa Hayashi 《Journal of Wood Science》2009,55(5):381-386
We examined the saccharification and fermentation of meals from Acacia mangium wood, Paraserianthes falcataria wood, and Elaeis guineensis trunk. The levels of enzymatic hydrolysis of cellulose and ethanol production were highest for P. falcataria wood and lowest for A. mangium wood. Ultrasonication pretreatment of meal further increased the rates of hydrolysis and ethanol production in meal from
P. falcataria wood. Through this pretreatment, hemicelluloses (xylan and xyloglucan) and cellulose were released in the meal from P. falcataria wood. Loosening of hemicellulose associations can be expected to make P. falcataria wood more useful for bioethanol production. 相似文献
10.
The germination of common alder (Alnus glutinosa (L.) Gaertn.) and downey birch (Betula pubescens Ehrh.) seeds is often poor in bare-root nurseries. The effect of a variety of seed coverings and a few seed pretreatments
on seedling emergence was examined in this study in an attempt to address this problem. Seeds of each species were sown in
trays containing nursery soil, covered with grit, gravel, sand, combinations of these coverings, a hydromulch or a sealed
plastic cloche and then incubated for 6 weeks at 17–20°C. The grit combined with sand or gravel, the hydromulch and the cloche
increased seedling emergence when compared with the standard grit. In another experiment, seeds of each species were fully
imbibed (FI) (>50% moisture content, MC), as per standard practice, or adjusted to target MC (TMC) (30–35% MC) levels, and
then chilled to release dormancy. Some seeds of each MC treatment were primed at 20°C for 2 days following chilling, after
which all seeds were evaluated in laboratory tests and a nursery trial. Germination potential of the FI seeds declined in
the lab tests by the second test date, which was reflected in low seedling emergence in the nursery in birch. The primed FI
seeds of alder germinated most rapidly in the nursery, but other effects were not significant. Seedling emergence was better
in the nursery in response to the TMC than the FI pretreatment in birch.
相似文献
Conor O’ReillyEmail: |
11.
Generic equations are proposed for stem, branch and foliage biomass of individual trees in even-aged pure stands of Cryptomeria japonica, Chamaecyparis obtusa and Larix kaempferi. Biomass data was collected from a total of 1,016 individual trees from 247 stands throughout Japan, and five regression
models were assessed by root mean square error, mean bias, fit index (FI), and AIC. The results show that a power equation
using diameter at breast height (dbh) and height is the most suitable for all species and components. This equation is more
accurate than the familiar power equation that uses ‘dbh2 height’, and it expresses the greater volume of branch and foliage mass of trees with a lower height/diameter ratio. A power
equation using dbh is more reasonable for models with dbh as the only independent variable and more accurate than a power
equation using ‘dbh2 height’ for estimating branch and foliage mass. Estimating error for branch and foliage mass is larger than that for stem
mass, but the entire aboveground biomass can be estimated with an error of less than 19%, except in the case of small trees
with dbh less than 10 cm. 相似文献
12.
Balbir Singh Rawat Vinod Prasad Khanduri Chandra Mohan Sharma 《林业研究》2008,19(2):125-130
研究赤霉素(GA3),冷湿和温度 对五个种源的印度冷杉(Abies pindrow)和长叶云杉(Picea smithiana)种子萌发的影响.种子被浸泡在GA3 (10 mg(L-1)中24小时,然后在3(5(C温度的条件下冷藏15天.设计4个温度(10(C, 15(C, 20(C 和 25(C)条件来促进种子的萌发.结果表明,浸泡和冷湿处理明显增加种子的萌发率.在10 (C时种子的萌发率最高.总体结果表明,种子被浸泡在GA3 (10 mg(L-1)中24小时,冷湿藏15天,可以有效地促进印度冷杉和长叶云杉的种子萌发.统计数据表明,浸泡处理、温度和种源以及与温度的相互作用都对种子的萌发有明显的影响. 相似文献
13.
Austrocedrus chilensis forests suffer from a disease caused by Phytophthora austrocedrae, which is found often in wet soils. We applied three widely used modelling techniques, with different data requirements,
to model disease potential distribution under current environmental conditions: Mahalanobis distance, Maxent and Logistic
regression. Each model was built using field data of health condition and landscape layers of environmental conditions (distance
to streams, slope, aspect, elevation, mean annual precipitation and soil pH NaF). We compared model predictions by area under
the receiver operating characteristic curve and Kappa statistics. A reasonable ability to predict observed disease distribution
was found for each of the three modelling techniques. However, Maxent and Logistic regression presented the best predictive
performance, with significant differences with respect to the Mahalanobis distance model. Our results suggested that if good
absence data are available, Logistic regression should be used in order to better discriminate sites with high risk of disease.
On the other hand, if absence data are not available or doubtful, Maxent could be a very good option. The three models predicted
that around 50% (49–56%) of the currently asymptomatic forests are located on sites at risk of disease according to abiotic
factors. Most of these asymptomatic forests surround the current diseased patches, at distances lower than 100 m from diseased
patches. Management considerations and the scope of future studies were discussed in this article. 相似文献
14.
Esteban Ceriani-Nakamurakare Mariel Slodowicz Cecilia Carmaran Paola Gonzalez-Audino 《Agroforestry Systems》2017,91(3):415-421
Megaplatypus mutatus (= Platypus mutatus) (Chapuis) is an ambrosia beetle native to South America that attacks live trees, mining deeply into the xylem through large tunnels. This activity weakens the structural integrity of the tree, causing severe stem-breakage and mortality. Attacks are initiated by pioneer males that select a host tree and build short nuptial galleries, to which they attract females using a sexual pheromone. Previously, we showed the potential for the strategy of pheromone-mediated mating disruption of M. mutatus in commercial poplar and hazelnut plantations in South America and Europe using polyethylene reservoir dispensers for pheromones. In the present work we replaced the polymeric reservoir dispensers by monolithic dispensers made by dispersion of the pheromone in natural waxes and the addition of kaolin and we found that: prior to pheromone deployment, the mean number of galleries per tree did not differ significantly between the control and treated plots and the same was observed after the mating disruption treatment for the control plot but not for treated plots, where the mean number of galleries were reduced. These findings confirm that mating disruption is a viable tool for management of M. mutatus in poplar plantations. Using natural wax dispensers has obvious advantages from an environmental point of view. 相似文献
15.
Marcus Hardie Daniel Mendham Ross Corkrey Eko Hardiyanto Alen Maydra Sabar Siregar Rianto Marolop Alun Wibowo 《New Forests》2018,49(1):87-104
Indonesia’s pulp and paper industry needs a large area of sustainably grown plantations to support its continued development. Acacia mangium has been the key species underpinning the pulp and paper industries in Sumatra, however increased disease pressure on A. mangium is expected to require large-scale conversion of Acacia plantations to Eucalyptus in the near future. The effect of such a large scale change in plantation species on soil moisture, for both tree production, and catchment hydrology is unknown. In this study we sought to characterize the impacts of plantation species (Acacia or Eucalyptus) and nitrogen management, on soil moisture, soil water depletion and depth to groundwater under stands of Acacia mangium and Eucalyptus pellita over the first 2–3 years after establishment. The study was conducted in experiments at four sites in Sumatra, Indonesia. Soil moisture and soil water depletion were not influenced by plantation species or fertilizer treatment. Soil moisture content and soil water depletion were strongly influenced by shallow groundwater at two of the four sites, however depth to groundwater did not influence stem growth. Results from the field trials cautiously suggest that large scale conversion of Acacia mangium to Eucalypt species in these regions is unlikely to result in increased moisture stress, nor is conversion of plantation species likely to lead to substantial differences in catchment hydrology. This study demonstrated the importance of conducting multi-site studies when investigating biophysical relationships in forest/plantation systems. 相似文献
16.
Priscila Ambrósio Moreira Walter Steenbock Nivaldo Peroni Mauricio Sedrez dos Reis 《Agroforestry Systems》2011,83(2):245-256
Bracatinga (Mimosa scabrella) is a legume tree species common in the early stages of succession in Araucaria angustifolia forests in southern Brazil. Bracatinga can form high-density monospecific stands called bracatingais. Its traditional management for charcoal production involves maintenance of the seed bank. Our objective was to analyze the
genetic diversity and structure of bracatingais to understand the mechanisms by which intraspecific diversity of M. scabrella is created and maintained in landscapes managed by family farmers in their agroforestry mosaics. We analyzed 14 bracatingais using 8 allozyme loci. We compared parental and progeny generation indices (7 loci) and described the mating system (9 loci)
of two progenies. Overall diversity was high: A = 2.69, H
o = 0.257, H
e = 0.382 and similar between populations. Overall fixation (F = 0.364) was similar to the fixation index (f = 0.329). The genetic divergence among populations was low (Θp = 0.052) but significant. The progenies’ genetic diversity values were similar to those of the previous generation (H
e pop11 = 0.342 vs. 0.420/H
e pop10 = 0.432 vs. 0.400). Progenies were compatible with half-sib and full-sib crossing expectations (θ
xy
= 0.204 and 0.194). Our data showed that there is a tendency for genetic structuring caused not only by the reproductive
system but also by genetic drift. It is very likely that the high genetic diversity is amplified by internal migration within
each bracatingal. This study showed that current landscape management can contribute to maintaining high levels of bracatinga genetic diversity, which contributes to its regional conservation. 相似文献
17.
The efficacy of NeemAzal powder, two local neem (Azadirachta indica
) products [neem seed powder (NSP) and neem seed oil (NSO)], as well as a local Lamiaceae, Plectranthus glandulosus leaf powder, applied at four different rates for the control of Sitophilus zeamais was determined. Mortality was recorded 1, 3, 7 and 14 days after S. zeamais infestation, followed by the determination of F1 progeny production. Grain damage, population increase and grain germination were assessed for treated grains that were stored
for 4 months. Grains treated with P. glandulosus powder and NSP had relatively low mortality (5.0–22.5%) after 3 days whereas NeemAzal and NSO had higher mortality (55.0–98.8%).
Maximum mortality of 99, 100, 96 and 74% were achieved for NeemAzal (12 g/kg after 14 days), NSO (4 ml/kg after 7 days), NSP
(40 g/kg after 14 days) and P. glandulosus powder (40 g/kg, after 14 days), respectively. In the same order, 7-day LC50 values were 0.02 g/kg, 1.46 ml/kg, 12.44 g/kg and 28.9 g/kg. The three neem products greatly reduced progeny emergence, while
P. glandulosus powder was less effective. NeemAzal protected the grains against S. zeamais damage better than the local neem products, which in turn provided far better grain protection against the weevil damage
than P. glandulosus powder. NeemAzal was superior to the local neem products in grain protection against germination loss, with P. glandulosus being the least effective. NeemAzal and NSO had sufficient efficacy to be a component of an integrated management package
for S. zeamais. 相似文献
18.
Yurika H.Komatsu Katherine Derlene Batagin-Piotto Gilvano Ebling Brondani Antnio Natal Gonalves Marcílio de Almeida 《林业研究》2011,22(2):209-215
Nodal segments from secondary branches of saplings of Phyllostachys bambusoides were inoculated in MS medium to assess the in vitro morphogenic response of leaf sheath through the induction to callogenesis by Picloram(4-amino-3,5,6-trichloropicolinic acid) at different concentrations of carbohydrate under the same conditions with presence or absence of luminosity.In our experiment,secondary explants were kept in MS medium containing 8.0 mg·L-1 of Picloram for the callus formation.Calluses were transferred in MS medium supplemented with sucrose,fructose and glucose(control,2%,4% and 6%).Results show that Picloram induced the callogenesis in leaf sheath.The secondary embryogenesis was formed in yellow-globular callus.The sucrose as carbohydrate source in the absence of light was more efficient to induce rhizogenesis.Glucose was more efficiency in the presence of light.Callogenic induction and further embryogenesis evidenced the competence and determination of leaf sheath cells. 相似文献
19.
The efficiency of the botanical insecticide (BI) NeemAzal T/S (containing 1% Azadirachtin A), on the basis of azadirachtin
applied in a dose of 20 g a.i. ha−1 against Brassica pod midge (Dasineura brassicae), has been monitored for 4 years. The biological efficiency of BI was compared with the efficiency of some synthetic insecticides.
It was ascertained that BI was very efficient in decreasing the number of damaged oilseed rape pods (ranging from 56.5 to
85.9% compared to untreated plants) and its efficiency was comparable with synthetic insecticides based on Chloronicotinyl
(Thiacloprid) and Neonicotinoid (Acetamiprid). BI’s efficiency was, in some years, even significantly higher compared to pyrethroid
(λ-cyhalothrin). The high biological efficiency of azadirachtin that we ascertained was significantly reflected in increasing
potential crop yields. The yield increase of azadirachtin ranged between 9.3 and 19.4% compared to the control sample. Azadirachtin
showed the highest yield for the whole time of experimentation, and in some years the yield increase was significantly higher
compared to some synthetic agents. 相似文献
20.
Low capsule set is a major factor limiting the productivity of Eucalyptus globulus seed orchards. This study tested the effect of flower density, as well as two common irrigation techniques on capsule and
seed set. Ramets with high flower density had significantly lower capsule set (69.7%) than those with low flower density (81.7%).
In a regulated deficit irrigation trial, the non-irrigated ramets set a higher proportion of capsules (63.6%) than the ramets
that received conventional irrigation (CI) (51.4%). In a partial root zone drying (PRD) trial, capsule set was highest in
the absence of irrigation (74.7%) followed by the PRD treatment (67.8%) and then CI (53.7%). The CI treatment tended to produce
the highest number of seed per capsule. Increased water availability resulted in increased vegetative growth, which was associated
with higher levels of abortion in developing capsules but those surviving tended to have higher seed set. It is argued that
the observed effects of irrigation and flower density can be explained by resource competition between vegetative and reproductive
growth as well as competition among reproductive structures themselves. 相似文献