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PubMed2005

Measuring the genetic structure of the pollen pool as the probability of paternal identity.

Contemporary pollen flow in forest plant species is measured by the probability of paternal identity (PPI) for two randomly sampled offspring, drawn from a single female, and contrasting that with PPI for two random offspring, drawn from different females. Two different estimation strategies have emerged: (a) an indirect approach, using the 'genetic structure' of the pollen received by different mothers and (b) a direct approach, based on parentage analysis. The indirect strategy is somewhat limited by the assumptions, but is widely useful. The direct approach is most appropriate where a large majority of the true fathers can be identified exactly, which is sometimes possible with high-resolution SSR markers. Using the parentage approach, we develop estimates of PPI, showing that the obvious estimates are severely biased, and providing an unbiased alternative. We then illustrate the methods with SSR data from a 36-tree isolated population of Pinus sylvestris from the Meseta region of Spain, for which categorical paternity assignment was available for over 95% of offspring. For all the females combined, we estimate that PPI=0.0425, indicating uneven male reproductive contributions. Different (but overlapping) arrays of males pollinate different females, and for the average female, PPI=0.317, indicating substantial 'pollen structure' for the population. We also relate the direct measures of PPI to those available from indirect approaches, and show that they are generally comparable.

Genetic Variation↗

PubMed2000

Effects of concurrent verbalization on a time-critical, dynamic decision-making task.

The authors investigated the effects of concurrent verbalization on students' performance on a time-critical, dynamic decision-making task. After training on Fire Chief (a computer microworld that simulates fighting a forest fire; M. M. Omodei & A. J. Wearing, 1993a), 60 research participants were allocated randomly to 1 of 3 experimental conditions: silence, associative verbalization, or procedural verbalization. Participants who verbalized the bases of their decisions (procedural verbalization) performed significantly worse on average than participants in the silence condition. There was a small but non-significant decrement in the performance of participants who verbalized thoughts other than the bases of their decisions while performing the task (associative verbalization). Their average level was between the levels of participants in the silence and procedural-verbalization conditions.

Adolescent↗

PubMed2003

Partitioning species diversity across landscapes and regions: a hierarchical analysis of alpha, beta, and gamma diversity.

Species diversity may be additively partitioned within and among samples (alpha and beta diversity) from hierarchically scaled studies to assess the proportion of the total diversity (gamma) found in different habitats, landscapes, or regions. We developed a statistical approach for testing null hypotheses that observed partitions of species richness or diversity indices differed from those expected by chance, and we illustrate these tests using data from a hierarchical study of forest-canopy beetles. Two null hypotheses were implemented using individual- and sample-based randomization tests to generate null distributions for alpha and beta components of diversity at multiple sampling scales. The two tests differed in their null distributions and power to detect statistically significant diversity components. Individual-based randomization was more powerful at all hierarchical levels and was sensitive to departures between observed and null partitions due to intraspecific aggregation of individuals. Sample-based randomization had less power but still may be useful for determining whether different habitats show a higher degree of differentiation in species diversity compared with random samples from the landscape. Null hypothesis tests provide a basis for inferences on partitions of species richness or diversity indices at multiple sampling levels, thereby increasing our understanding of how alpha and beta diversity change across spatial scales.

Animals↗

PubMed1991

Attraction of Glossina longipalpis (Diptera: Glossinidae) in Guinea-Bissau to odor-baited biconical traps.

The catches of tsetse flies, Stomoxys, and tabanids in biconial traps baited with different synthetic odors were compared in the Jopá-Cobiana Forest, northwestern Guinea-Bissau. Thirty-six traps, the baits of which were randomly interchanged each of 10 sampling days, were baited either with (a) 1-octen-3-ol (octenol) + phenols [4-methylphenol + 3-propylphenol] + acetone + N'dama cow urine ("urine"), (b) octenol + phenols + acetone, (c) octenol + phenols, (d) acetone, (e) acetone + urine, or (f) urine. Six of the traps were not baited (controls). A total of 3,172 tsetse flies (96% Glossina longipalpis Widemann, 3% G. morsitans submorsitans Newstead, and 1% G. palpalis gambiensis Vanderplank), 286 Stomoxys, and 571 Tabanidae was captured. G. longipalpis was caught in statistically greater numbers in traps baited with octenol + phenols + acetone. Traps baited with octenol + phenols, with or without acetone, caught the greatest numbers of tabanids. N'dama urine did not increase the catch of G. longipalpis. Stomoxys was not significantly attracted to any of the odors.

Animals↗

PubMed1997

Data mining of inputs: analysing magnitude and functional measures.

The problem of data encoding and feature selection for training back-propagation neural networks is well known. The basic principles are to avoid encrypting the underlying structure of the data, and to avoid using irrelevant inputs. This is not easy in the real world, where we often receive data which has been processed by at least one previous user. The data may contain too many instances of some class, and too few instances of other classes. Real data sets often include many irrelevant or redundant input fields. This paper examines the use of weight matrix analysis techniques and functional measures using two real (and hence noisy) data sets. The first part of this paper examines the use of the weight matrix of the trained neural network itself to determine which inputs are significant. A new technique is introduced and compared with two other techniques from the literature. We present our experience and results on some satellite data augmented by a terrain model. The task was to predict the forest supra-type based on the available information. A brute force technique eliminating randomly selected inputs was used to validate our approach. The second part of this paper examines the use of measures to determine the functional contribution of inputs to outputs. Inputs which include minor but unique information to the network are more significant than inputs with higher magnitude contribution but providing redundant information, which is also provided by another input. A comparison is made to sensitivity analysis, where the sensitivity of outputs to input perturbation is used as a measure of the significance of inputs. This paper presents a novel functional analysis of the weight matrix based on a technique developed for determining the behavioral significance of hidden neurons. This is compared with the application of the same technique to the training and test data. Finally, a novel aggregation technique is introduced.

Algorithms↗

PubMed2003

Evolutionary plantographics.

This letter describes an evolutionary system for creating lifelike three-dimensional plants and flowers, our main goal being the facilitation of producing realistic plant imagery. With these two goals in mind--ease of generation and realism--we designed the plant genotype and the genotype-to-phenotype mapping. Diversity in our system comes about through two distinct processes--evolution and randomization--allowing the creation not only of single plants but of entire gardens and forests. Thus, we are able to readily produce natural-looking artificial scenes.

Biological Evolution↗

PubMed2006

Systematic review on the short-term outcome of laparoscopic resection for colon and rectosigmoid cancer.

OBJECTIVE: Several large randomized controlled trials on laparoscopic resection for colon and rectosigmoid cancer have recently been published. There is a need to provide an up-to-date systematic review in this subject. METHODS: A literature search of all published randomized trials in English between January 1991 and September 2005 was obtained, from Ovid MEDLINE, EMBASE, CINAHL, and All EBM Reviews (Cochrane Central Register of Controlled Trial, Cochrane Database of Systemic Review, and Database of Abstracts of Reviews of Effects), including e-links to the related articles. Two independent assessors reviewed the trials using a standardized protocol. Where means and standard deviations were available, meta-analysis was performed using the Forest plot review. Studies where medians and ranges were presented were separately analysed. RESULTS: A total of 17 randomized controlled trials with 4013 procedures were reviewed. The conversion rate varied widely between studies and was lowest in single-Centre trials. There were no significant differences in overall and surgical complication rate, anastomotic leak rate, re-operation rate and oncological clearance. However, laparoscopic resection has a significantly lower peri-operative mortality (odds ratio 0.33; P = 0.005), lower wound complications (odds ratio 0.65; P = 0.01), less blood loss (weighted mean difference 0.11 l; P < 0.00001) and reduced postoperative pain scores by 12.6% with reduction of requirements for narcotic analgesia by 30.7%. After laparoscopic surgery, patients passed flatus 38.8% earlier (weighted mean difference 27.6 h; P < 0.00001) and had bowel movement 21.0% earlier (weighted mean difference 23.9 h; P < 0.00001) and resumed oral diet 28.3% sooner than patients in the open group (weighted mean difference 27.3 h; P < 0.00001). Patients were discharged 19.1% earlier after laparoscopic surgery than open surgery (weighted mean difference 1.7 days; P < 0.00001). Laparoscopic resection took 28.7% longer (weighted mean difference 40.1 min; P < 0.00001) to perform. CONCLUSIONS: Laparoscopic resection for colon and rectosigmoid cancer is feasible, safe and has many short-term benefits.

Colectomy↗

PubMed2004

Using decision forest to classify prostate cancer samples on the basis of SELDI-TOF MS data: assessing chance correlation and prediction confidence.

Class prediction using "omics" data is playing an increasing role in toxicogenomics, diagnosis/prognosis, and risk assessment. These data are usually noisy and represented by relatively few samples and a very large number of predictor variables (e.g., genes of DNA microarray data or m/z peaks of mass spectrometry data). These characteristics manifest the importance of assessing potential random correlation and overfitting of noise for a classification model based on omics data. We present a novel classification method, decision forest (DF), for class prediction using omics data. DF combines the results of multiple heterogeneous but comparable decision tree (DT) models to produce a consensus prediction. The method is less prone to overfitting of noise and chance correlation. A DF model was developed to predict presence of prostate cancer using a proteomic data set generated from surface-enhanced laser deposition/ionization time-of-flight mass spectrometry (SELDI-TOF MS). The degree of chance correlation and prediction confidence of the model was rigorously assessed by extensive cross-validation and randomization testing. Comparison of model prediction with imposed random correlation demonstrated biologic relevance of the model and the reduction of overfitting in DF. Furthermore, two confidence levels (high and low confidences) were assigned to each prediction, where most misclassifications were associated with the low-confidence region. For the high-confidence prediction, the model achieved 99.2% sensitivity and 98.2% specificity. The model also identified a list of significant peaks that could be useful for biomarker identification. DF should be equally applicable to other omics data such as gene expression data or metabolomic data. The DF algorithm is available upon request.

Decision Support Techniques↗

PubMed2005

Prescribed burning effects on summer elk forage availability in the subalpine zone, Banff National Park, Canada.

The effects of prescribed burning on forage abundance and suitability for elk (Cervus elaphus) during the snow-free season was evaluated in east-central Banff National Park, Canada. Six coniferous forest and mixed shrub-herb plant communities (n=144 plots), and 5223ha of burned (n=131) vegetation <12 years old were sampled using a stratified semi-random design. Sampling units represented various combinations of vegetation, terrain conditions, and stand ages that were derived from digital biophysical data, with plant communities the basic unit of analysis. Burning coniferous forest stands reduced woody biomass, and increased herbaceous forage from 146 to 790 kg/ha. Increases commonly occurred in the percent cover of hairy wild rye (Leymus innovatus (Beal) Pigler) and fireweed (Chamerion angustifolium (L.) Holub.). The herbaceous components of mixed shrub-herb communities increased from 336-747 kg/ha to 517-1104 kg/ha in response to burning (P<0.025, Mann-Whitney U-test). Browse biomass (mostly Salix spp. and Betula nana L.) increased >or=220% (P<or=0.003, Mann-Whitney U-test) from 653 kg/ha in deciduous shrub types. Elk preferences for unburned and burned vegetation-types were assessed as low and moderate, respectively. Potential summer carrying capacity, based on forage availability, increased from eight to 28 elk/100 km2 within burned areas, whereas spring grazing potential rose from 13 to 45 elk/100 km2. Most of the increase (73%) was attributable to changes within burned Engelmann Spruce stands, which composed 58% of the burned area.

Alberta↗

PubMed2005

Searching on patch networks using correlated random walks: space usage and optimal foraging predictions using Markov chain models.

We describe a novel representation of a discrete correlated random walk as the transition matrix of a Markov chain with the displacements as the states. Such a representation makes it possible to utilize results from the theory of absorbing Markov chains, to make biologically interesting predictions without having to resort to Monte Carlo simulations. Our motivation for constructing such a representation is to explore the relationship between the movement strategy of an animal searching for resources upon a network of patches, and its consequent utilization of space and foraging success. As an illustrative case study, we have determined the optimal movement strategy and the consequent usage of space for a central place forager utilizing a continuous movement space which is discretized as a hexagonal lattice. The optimal movement strategy determines the size of the optimal home range. In this example, the animal uses mnemokinesis, which is a sinuosity regulating mechanism, to return it to the central place. The movement strategy thus refers to the choice of the intrinsic path sinuosity and the strength of the mnemokinetic mechanism. Although the movement space has been discretized as a regular lattice in this example, the method can be readily applied to naturally compartmentalized movement spaces, such as forest canopy networks. This paper is thus an attempt at incorporating results from the theory of random walk-based animal movements into Foraging Theory.

Animals↗

PubMed2006

Meta-DiSc: a software for meta-analysis of test accuracy data.

BACKGROUND: Systematic reviews and meta-analyses of test accuracy studies are increasingly being recognised as central in guiding clinical practice. However, there is currently no dedicated and comprehensive software for meta-analysis of diagnostic data. In this article, we present Meta-DiSc, a Windows-based, user-friendly, freely available (for academic use) software that we have developed, piloted, and validated to perform diagnostic meta-analysis. RESULTS: Meta-DiSc a) allows exploration of heterogeneity, with a variety of statistics including chi-square, I-squared and Spearman correlation tests, b) implements meta-regression techniques to explore the relationships between study characteristics and accuracy estimates, c) performs statistical pooling of sensitivities, specificities, likelihood ratios and diagnostic odds ratios using fixed and random effects models, both overall and in subgroups and d) produces high quality figures, including forest plots and summary receiver operating characteristic curves that can be exported for use in manuscripts for publication. All computational algorithms have been validated through comparison with different statistical tools and published meta-analyses. Meta-DiSc has a Graphical User Interface with roll-down menus, dialog boxes, and online help facilities. CONCLUSION: Meta-DiSc is a comprehensive and dedicated test accuracy meta-analysis software. It has already been used and cited in several meta-analyses published in high-ranking journals. The software is publicly available at http://www.hrc.es/investigacion/metadisc_en.htm.

Clinical Laboratory Techniques↗

PubMed1997

[An entire rain forest can be screened at pharmaceutical industry's laboratories].

The pharmaceutical industry has long been heavily reliant on natural products, and today more than half of the twenty best-selling pharmaceuticals are derived from natural sources. Hitherto sample collection from fauna and flora has been based on an ethnobotanical approach involving traditional healers and oral histories of indigenous peoples as sources of information on folk uses of plants and organisms. In the future, however, random sampling combined with automated high-throughput screening (HTS) may come to the forefront in drug design, enabling extensive libraries of active compounds to be built up, and rendering local knowledge largely irrelevant. New technological advances in chemistry, molecular biology and data processing are combined in automated systems whereby HTS, based on bioassay-guided fractionation procedures, is used to isolate active compounds, and enabling the chemical structure of isolated compounds to be determined within 24 hours. The combination of the speed of HTS, and a remarkable decrease in the amount of sample required for the isolation and structure determination of natural compounds, has improved our ability to find unique natural products for drug development. Moreover, it has already been demonstrated that, owing to the relatively minute amounts of material required for HTS, this random sampling approach to bioprospecting for the purposes of drug will benefit efforts to conserve such sensitive biosystems as the rain forests and marine ecosystems. Thus, this technology would seem to be more compatible with the needs of modern drug design in the pharmaceutical industry that the ethnobotanical approach.

Drug Industry↗

PubMed2026

Effects of time-restricted eating on markers of glucose metabolism and regulation in individuals with prediabetes or type 2 diabetes: a systematic review and meta-analysis of randomised controlled trials.

AIMS/HYPOTHESIS: This systematic review and meta-analysis aimed to investigate the effects of time-restricted eating (TRE) on glucose metabolism and regulation in individuals with prediabetes (fasting blood glucose of 5.6-6.9 mmol/l or HbA1c of 39-47 mmol/mol [5.7-6.4%]) or type 2 diabetes (fasting blood glucose ≥7 mmol/l or HbA1c ≥48 mmol/mol [6.5%]). METHODS: A literature search was performed in MEDLINE, Embase and CENTRAL from inception to 5 August 2025. Moreover, forward and backward citation searches were performed. Eligible studies were RCTs in adults with prediabetes or type 2 diabetes, lasting ≥2 weeks, reporting markers of glucose metabolism and regulation, comparing TRE (≤12 h eating window) with a non-time-restricted control diet. Studies involving pregnancy, other fasting regimens, or non-peer-reviewed publications were excluded. Data were pooled as weighted mean differences with 95% CIs using random-effects generic inverse variance models in Cochrane Review Manager Web, and results are presented as forest plots. The certainty of evidence was defined using Grading of Recommendations, Assessment, Development and Evaluations methodology, and risk of bias was estimated by using the Revised Cochrane risk-of-bias tool for randomised trials (RoB 2). RESULTS: Out of 2043 records identified through the database search, as well as 1249 from forward and backward citation searches, ten RCTs including 599 participants were included. The mean length of the studies was 4 months, and the eating windows ranged from 4 to 10 h per day. The pooled meta-analysis showed no overall effect of TRE on HbA1c (-3.33 mmol/mol; 95% CI -6.87, 0.20 (-0.30% points; -0.63, 0.02); p=0.06, moderate certainty). Nevertheless, following stratification by subgroups, TRE resulted in a reduction in HbA1c of 0.93 mmol/mol (-1.70, -0.17 [-0.09% points; -0.16, -0.02]; p=0.02) in individuals with prediabetes but not in individuals with type 2 diabetes (-4.68 mmol/mol; -10.08, 0.72 (-0.43% points; -0.92, 0.07); p=0.09). TRE reduced fasting blood glucose in the pooled analysis (-0.30 mmol/l; -0.53, -0.07; p<0.01, moderate certainty) as well as in the subgroup analyses in individuals with prediabetes (-0.14 mmol/l; -0.27, -0.01; p=0.03) and with type 2 diabetes (-0.48 mmol/l; -0.78, -0.17; p<0.01). Moreover, TRE lowered body weight by 1.6 kg (-2.2, -1.0; p<0.001) in the pooled analysis. The evidence was limited by imprecision arising from wide confidence intervals in some of the included studies, which may be due to small sample sizes. Lastly, the effects of TRE on markers of insulin sensitivity, beta cell function and continuous glucose monitoring measurements were inconclusive. CONCLUSIONS/INTERPRETATION: Moderate-certainty evidence indicates that TRE reduces fasting blood glucose but not HbA1c. The subgroup analyses revealed that TRE improved HbA1c and fasting glucose in individuals with prediabetes and improved fasting glucose in individuals with type 2 diabetes. Future large-scale studies should investigate long-term effects of TRE in prevention and treatment of type 2 diabetes. TRIAL REGISTRATION: PROSPERO CRD42024523591 FUNDING: This research received no specific grant from any funding agency in the public, commercial or not-for-profit sectors. Three authors (JS, A-DT, THA) are employed at Steno Diabetes Center Copenhagen, a public hospital and research institution under the Capital Region of Denmark, partly funded by a grant from the Novo Nordisk Foundation.

Humans↗

PubMed2001

Acting, behaving, and the selfless basis of metaperception.

The desire to create a particular impression of oneself to others is a fundamental interpersonal motive that should be followed by an assessment of the success of the self-presentation. The authors integrate the areas of self-presentation and metaperception in the present research by assigning participants to enact roles during 2 dyadic interactions and measuring the actors' metaperceptions and their partners' trait judgments. They found a high level of accuracy in actors' metaperceptions but no accuracy in partners' trait judgments of the actors. Instead, partners' trait judgments corresponded closely to the actors interpersonal behavior, indicating that there was little or no "personality leakage" in the actors' behavior. Random assignment to role created a situation in which private self was uncorrelated with public self. Results indicate that actors were able to disregard their self-concepts when determining the impressions they created.

Affect↗

PubMed1997

Effects of community-wide use of lambdacyhalothrin-impregnated bednets on malaria vectors in rural Sierra Leone.

The effect of community-wide use of bednets treated with lambdacyhalothrin 10 mg/m2 on the malaria vector Anopheles gambiae (forest form) was evaluated in Sierra Leone. Sixteen similar villages near the town of Bo were randomly allocated either to remain without nets or to receive treated bednets for all inhabitants, with effect from June 1992. Mosquitoes were sampled using human biting catches on verandas, light-trap catch (beside an occupied untreated bednet), window exit-trap catch and pyrethrum spray collections. During the first year of intervention (June 1992 to July 1993) the treated bednets provided personal protection for people sleeping under them, but had very little impact on densities of An.gambiae collected on human bait. The human blood index (HBI) of An.gambiae was not affected (HBI = 99% in villages with and without nets). An.gambiae parous rates were significantly reduced in all intervention villages, but malaria sporozoite rates fell in only some of the villages. These results are intermediate between those obtained from other projects in Tanzania and Burkina Faso, where treated bednets reduced man-biting, parity and sporozoite rates, versus The Gambia where treated bednets had no significant impact on any of these factors. Possible reasons for these contrasted findings are discussed.

Animals↗

PubMedDate not supplied

Risk factors of malaria in the fringes of an evergreen monsoon forest of Arunachal Pradesh.

BACKGROUND: The forested hilly and foothill regions of north-east India are highly endemic for malaria and have a distinct epidemiological pattern. Nearly half the reported cases of malaria are from these areas. A knowledge of the risk factors in this eco-geographic entity may be helpful in formulating a specific control strategy. Hence, we conducted a community-based epidemiological study in a hilly, forested terrain of Arunachal Pradesh and examined different socio-demographic factors to identify those predisposing to the occurrence of malaria, especially Plasmodium falciparum infection, in such areas. METHODS: Four epidemiological surveys were carried out during 1997 in 7 villages located at the fringes of a forest (total population: 1177) under Nompong Primary Health Centre of Changlang district, Arunachal Pradesh. Blood slides were collected randomly from the inhabitants, irrespective of their fever status, ensuring at least 50% coverage. One hundred and thirty-four microscopically confirmed Plasmodium falciparum cases were identified and 536 controls were randomly selected from the list of uninfected inhabitants. Relevant socio-demographic information was obtained from both cases and controls. The data were analysed by simple and multiple logistic regression using the unconditional maximum likelihood method. RESULTS: Factors which were found to be strongly associated with Plasmodium falciparum malaria on univariate analysis were age, ethnicity, village of residence and accessibility to the nearest health care facility. However, in multiple regression analysis, after controlling for the effects of confounding variables, the only risk factor identified was accessibility to the nearest health care facility (adjusted odds ratio: 4.5; 95% CI: 1.8-11.3; p < 0.0001 for those at a distance of 2-8 km and adjusted odds ratio: 11.1; 95% CI: 4.1-30.0; p < 0.0001 for those > 8 km away). CONCLUSION: Distance, particularly non-motorable distance, from the place of residence to the nearest health care facility was a major risk factor for malaria in this hilly forested terrain. This indicates the need for special efforts to detect cases early and institute treatment promptly in such areas of the north-eastern region, so as to reduce the morbidity and mortality of malaria.

Adolescent↗

PubMed2005

A case study of forest management planning using a new heuristic algorithm.

We present an approach to generate and evaluate different silvicultural development paths and to optimize the development of a Norway spruce stand, using a long-term planning horizon. To generate a silvicultural path, the maximum stand density was applied. At each thinning event, three possible thinning intensities (10, 20, 30% of the stem number per ha) were randomly chosen. A search algorithm known as modified Accelerated Simulated Annealing (mASA) was used to estimate the optimum combination of stand paths for a given forest as a whole. Production and economic management objectives were considered and then compared. The economic criterion was the Expected Stand Value (ESV) with a 4% discount rate. The generated data set of 38 Norway spruce stands (comprising a total of 123.8 ha) was used in the case study. The result with the best combination of paths was presented in a digitized forest map. Forest management simulation was performed using a specially developed computer program, for a planning horizon of 20 years. The mASA proved to be an effective search method for identifying optimum paths.

Algorithms↗

PubMed2003

Positive assortative mating with selection restrictions on group coancestry enhances gain while conserving genetic diversity in long-term forest tree breeding.

Selection and mating principles in a closed breeding population (BP) were studied by computer simulation. The BP was advanced, either by random assortment of mates (RAM), or by positive assortative mating (PAM). Selection was done with high precision using clonal testing. Selection considered both genetic gain and gene diversity by "group-merit selection", i.e. selection for breeding value weighted by group coancestry of the selected individuals. A range of weights on group coancestry was applied during selection to vary parent contributions and thereby adjust the balance between gain and diversity. This resulted in a series of scenarios with low to high effective population sizes measured by status effective number. Production populations (PP) were selected only for gain, as a subset of the BP. PAM improved gain in the PP substantially, by increasing the additive variance (i.e. the gain potential) of the BP. This effect was more pronounced under restricted selection when parent contributions to the next generation were more balanced with within-family selection as the extreme, i.e. when a higher status effective number was maintained in the BP. In that case, the additional gain over the BP mean for the clone PP and seed PPs was 32 and 84% higher, respectively, for PAM than for RAM in generation 5. PAM did not reduce gene diversity of the BP but increased inbreeding, and in that way caused a departure from Hardy-Weinberg equilibrium. The effect of inbreeding was eliminated by recombination during the production of seed orchard progeny. Also, for a given level of inbreeding in the seed orchard progeny or in a mixture of genotypes selected for clonal deployment, gain was higher for PAM than for RAM. After including inbreeding depression in the simulation, inbreeding was counteracted by selection, and the enhancement of PAM on production population gain was slightly reduced. In the presence of inbreeding depression the greatest PP gain was achieved at still higher levels of status effective number, i.e. when more gene diversity was conserved in the BP. Thus, the combination of precise selection and PAM resulted in close to maximal short-term PP gain, while conserving maximal gene diversity in the BP.

Computer Simulation↗