Reproductive Success of Two Eucalyptus Hybrid Populations. II. Comparison of Predispersal Seed Parameters

1981 ◽  
Vol 29 (1) ◽  
pp. 37 ◽  
Author(s):  
DW Drake
Keyword(s):  
Reproductive Success ◽  
Single Species ◽  
Hybrid Population ◽  
Total Output ◽  
Species Trees ◽  
Hybrid Seeds ◽  
Seed Output ◽  
Total Seed ◽  
Insect Predation ◽  
Very High

The reproductive success of E. melanophloia × E. crebra and E. populnea × E. crebra hybrid populations is examined in terms of seed output. Predispersal seed losses and outputs from fruits and trees of hybrids and species in mixed- and single-species stands are presented. The contribution of the hybrid population to the total eucalypt seed output is considered by including in the estimates the numbers of hybrid and species trees per unit area of ecotone. Losses of E. melanophloia × E. crebra hybrid seeds through abortion, insect predation and fungal infection are significantly greater than losses of parent seeds and seeds of the other hybrid, and average 70% overall compared with 22% for each parent. If losses through bud maturation failure are included, 93% of the hybrid potential is lost. Hybrid outputs of 7 × 103 whole seeds per tree and 22 × 104 per ha of ecotone are respectively 1.5%, and 0.3% of the total seed output of the three taxa. Overall losses in the E. populnea × E. crebra hybrid system are much lower and less important to survival. The effect on seed number is dependent upon seed potential per fruit. E. populnea is the least affected (9% loss, very high potential), E. crebra the worst (21%, very low) and the hybrids are intermediate and in a relatively strong competitive position (20%, intermediate). Hybrid outputs of 145 × 103 seeds per tree and 23 × 103 per ha are respectively 21% and 17% of the total output. The significance of these results is discussed in relation to the reliance of eucalypts upon a high seed output strategy for survival and to the hybridization success of the two systems.

Reproductive Success of Two Eucalyptus Hybrid Populations. I. Generalized Seed Output Model and Comparison of Fruit Parameters

1981 ◽  
Vol 29 (1) ◽  
pp. 25 ◽  
Author(s):  
DW Drake
Keyword(s):  
Reproductive Success ◽  
Reproductive Effort ◽  
Significant Loss ◽  
Hybrid Population ◽  
Subsequent Paper ◽  
Species Trees ◽  
Seed Output ◽  
Eucalyptus Hybrid ◽  
Canopy Size ◽  
Two Populations

The dynamics of the reproductive success of two interspecific Eucalyptus hybrid populations are examined here and in a subsequent paper in relation to a generalized model of seed output of a single plant. The model describes a structural system of seed output per plant under both physiological and physical regulation. It can readily be extended to a population model and to postdispersal reproductive stages. Fruit loss, output and damage in the two populations are presented. The E. melanophloia × E. crebra hybrids are considerably less fertile than their parent species. Significant loss of reproductive structures during maturation and low reproductive effort, together with variable canopy size and proportion of canopy bearing fruits, result in the fruit output per average hybrid tree being 10% of either of the average species trees. Biotic damage to surviving hybrid fruits by an insect and a fungus is individually significantly greater than levels suffered by the species and together account for an average of 56% of fruits compared with 16% for either species. Damage and loss levels to these hybrids are more or less constant in space and time and constitute a strong selective force against these hybrids. In contrast, fruit loss parameters are low and differences between the taxa are non-significant throughout the E.populnea × E. crebra hybrid system, resulting in hybrid fertility about equal to the fertilities of the parents. These contrasting results are discussed in relation to hybrid frequencies in the ecotone and levels of hybrid population development.

scholarly journals Reconciliation of Gene and Species Trees

2014 ◽  
Vol 2014 ◽  
pp. 1-22 ◽  
Author(s):  
L. Y. Rusin ◽  
E. V. Lyubetskaya ◽  
K. Y. Gorbunov ◽  
V. A. Lyubetsky
Keyword(s):  
Time Scales ◽  
Gene Evolution ◽  
Single Species ◽  
Species Tree ◽  
Gene Duplications ◽  
Species Trees ◽  
Evolutionary Scenario ◽  
Algorithmic Construction ◽  
Basic Ideas ◽  
Horizontal Transfers

The first part of the paper briefly overviews the problem of gene and species trees reconciliation with the focus on defining and algorithmic construction of the evolutionary scenario. Basic ideas are discussed for the aspects of mapping definitions, costs of the mapping and evolutionary scenario, imposing time scales on a scenario, incorporating horizontal gene transfers, binarization and reconciliation of polytomous trees, and construction of species trees and scenarios. The review does not intend to cover the vast diversity of literature published on these subjects. Instead, the authors strived to overview the problem of the evolutionary scenario as a central concept in many areas of evolutionary research. The second part provides detailed mathematical proofs for the solutions of two problems: (i) inferring a gene evolution along a species tree accounting for various types of evolutionary events and (ii) trees reconciliation into a single species tree when only gene duplications and losses are allowed. All proposed algorithms have a cubic time complexity and are mathematically proved to find exact solutions. Solving algorithms for problem (ii) can be naturally extended to incorporate horizontal transfers, other evolutionary events, and time scales on the species tree.

scholarly journals Experimental Test of the Combined Effects of Water Availability and Flowering Time on Pollinator Visitation and Seed Set

2021 ◽  
Vol 9 ◽  
Author(s):  
M. Kate Gallagher ◽  
Diane R. Campbell
Keyword(s):  
Climate Change ◽  
Reproductive Success ◽  
Seed Production ◽  
Water Availability ◽  
Seed Mass ◽  
Single Species ◽  
Flowering Phenology ◽  
Abiotic Factor ◽  
Pollinator Visitation ◽  
Plant Reproductive Success

Climate change is likely to alter both flowering phenology and water availability for plants. Either of these changes alone can affect pollinator visitation and plant reproductive success. The relative impacts of phenology and water, and whether they interact in their impacts on plant reproductive success remain, however, largely unexplored. We manipulated flowering phenology and soil moisture in a factorial experiment with the subalpine perennial Mertensia ciliata (Boraginaceae). We examined responses of floral traits, floral abundance, pollinator visitation, and composition of visits by bumblebees vs. other pollinators. To determine the net effects on plant reproductive success, we also measured seed production and seed mass. Reduced water led to shorter, narrower flowers that produced less nectar. Late flowering plants produced fewer and shorter flowers. Both flowering phenology and water availability influenced pollination and reproductive success. Differences in flowering phenology had greater effects on pollinator visitation than did changes in water availability, but the reverse was true for seed production and mass, which were enhanced by greater water availability. The probability of receiving a flower visit declined over the season, coinciding with a decline in floral abundance in the arrays. Among plants receiving visits, both the visitation rate and percent of non-bumblebee visitors declined after the first week and remained low until the final week. We detected interactions of phenology and water on pollinator visitor composition, in which plants subject to drought were the only group to experience a late-season resurgence in visits by solitary bees and flies. Despite that interaction, net reproductive success measured as seed production responded additively to the two manipulations of water and phenology. Commonly observed declines in flower size and reward due to drought or shifts in phenology may not necessarily result in reduced plant reproductive success, which in M. ciliata responded more directly to water availability. The results highlight the need to go beyond studying single responses to climate changes, such as either phenology of a single species or how it experiences an abiotic factor, in order to understand how climate change may affect plant reproductive success.

scholarly journals SARS, SARS-Cov-2 and MERS are the Same Viral Species, Clades within Bat Beta-Coronaviruses

2020 ◽  
Author(s):  
Michael J. Wise
Keyword(s):  
Severe Acute Respiratory Syndrome ◽  
Phylogenetic Tree ◽  
Protein Level ◽  
Phylogenetic Trees ◽  
Single Species ◽  
Planetary Health ◽  
Phylogenetic Reconstructions ◽  
Human Coronaviruses ◽  
Very High

SARS-CoV-2 and SARS are human coronaviruses of zoonotic origin that first transferred from bats to humans in China.They are regarded as sister clades within the viral species Severe Acute Respiratory Syndrome-Related Coronavirus, anda chain of bat beta-coronavirus strains links SARS and SARS-CoV-2. Here I report phylogenetic tree reconstructions in which SARS and SARS-CoV-2 are placed together with related bat strains. Single-species models are favoured over speciation models. This is also the case when the phylogenetic trees for MERS and its related beta-coronaviruses in camels, bats and hedgehogs is reconstructed, and even when the datasets are combined. Dated phylogenetic reconstructions suggest that both SARS-like and MERS-like beta-coronaviruseshave been circulating for many years. I therefore proposethat SARS, SARS-CoV-2 and MERS may be better thought of as sub-clades of bat beta-coronavirus that have on occasion transferred to humans. Looking specifically at SARS-CoV-2, there are also very high levels of conservation evident at the protein level, suggesting that multiple possible targets exist for vaccines or other therapeutics. Finally, these long-running reservoirs emphasise the need for ongoing wide-spreadsurveillance and reporting, and the importance of Planetary Health.

scholarly journals UglyTrees: a browser-based multispecies coalescent tree visualizer

2020 ◽  
Author(s):  
Jordan Douglas
Keyword(s):  
Visual Tracking ◽  
Posterior Distribution ◽  
Single Species ◽  
Web Browsers ◽  
Gene Trees ◽  
Species Trees ◽  
Multiple Gene ◽  
Multispecies Coalescent ◽  
Coalescent Tree ◽  
Ready Access

Abstract Summary Visualization is a vital task in phylogenetics and yet there is a deficit in programs which visualize the multispecies coalescent (MSC) model. UglyTrees (UT) is an easy-to-use program for visualizing multiple gene trees embedded within a single species trees. The mapping between gene and species nodes is automatically detected allowing for ready access to the program. UT can scrape the contents of a website for MSC analyses, enabling the sharing of interactive MSC figures through optional parameters in the URL. If a posterior distribution is uploaded, the transitions between MSC states are animated allowing the visual tracking of trees throughout the sequence. Availability and implementation UT runs in all major web browsers including mobile devices, and is hosted at www.uglytrees.nz. The MIT-licensed code is available at https://github.com/UglyTrees/uglytrees.github.io.

HEAVY METALS IN EDIBLE MUSHROOMS

2002 ◽  
Vol 12 (03n04) ◽  
pp. 117-124 ◽  
Author(s):  
KAARE KEMP
Keyword(s):  
Heavy Metals ◽  
Single Species ◽  
Edible Mushrooms ◽  
High Toxicity ◽  
Pixe Analysis ◽  
The Family ◽  
High Degree ◽  
Very High

It has been reported that edible mushrooms are able to enrich the concentrations of several heavy metals. The Cd has especially drawn attention due to its high toxicity. By using PIXE analysis for the determination of the heavy metals it is possible to obtain a screening of the content of a wide number of elements. By analysing different species it is shown that one or a few elements may be characteristic for a single species. It is especially remarkable that several species of the family Agaricaceae are enriching Ag to a very high degree (up to 200 ppm).

scholarly journals Seeding development potential and prospects of NASA 29 hybrid corn in North Sulawesi Province

2021 ◽  
Vol 911 (1) ◽  
pp. 012089
Author(s):  
Supratman Sirih ◽  
Jefny B. Markus Rawung ◽  
Rita Indrasti ◽  
Ronald T. P. Hutapea ◽  
Yusuf
Keyword(s):  
Production Data ◽  
Rating Score ◽  
Corn Production ◽  
Maize Seeds ◽  
North Sulawesi ◽  
Hybrid Seeds ◽  
The Government ◽  
Hybrid Maize ◽  
Government Production ◽  
Very High

Abstract North Sulawesi is one of the areas with great potential in supporting the production and productivity of hybrid maize seeds. The land available for the cultivation of hybrid maize seeds is very wide, the requirements for agro-climatic are simple, the technology is readily available, so that the prospect of profits for the cultivator is quite large. Most of the maize farmers in North Sulawesi tend to use hybrid seeds. This is because the yield obtained is very high, however, the availability of hybrid seeds is very limited, even if available, the price is quite expensive. Farmers are currently still dependent on seed assistance from the Government. Production of seeds through breeder farmers as a solution in order to increase corn production. NASA 29 variety is a new superior variety derived from male parents G102612 and Mal 03 as female parents. The results of the interview showed that 86% of the 25 respondents of maize farmers gave an average rating score of 3.8. This shows that they really like the characteristics of the plant. The production data for NASA 29 seed candidates is 3.6 tons / ha. These results indicate that the prospect of hybrid maize seeding business is profitable for breeder farmers.

PARENTAL CARE AND PARENTAGE IN MONOGAMOUS GREAT SPOTTED WOODPECKERS (PICOIDES MAJOR) AND MIDDLE SPOTTED WOODPECKERS (PICOIDES MEDIUS)

Behaviour ◽  
2001 ◽  
Vol 138 (10) ◽  
pp. 1259-1285 ◽  
Author(s):  
Hans Winkler ◽  
Klaus Michalek
Keyword(s):  
Reproductive Success ◽  
Parental Care ◽  
Dna Fingerprinting ◽  
Paternal Care ◽  
Brood Care ◽  
Low Frequencies ◽  
Male Investment ◽  
Paternal Effort ◽  
Certainty Of Paternity ◽  
Very High

AbstractPaternal effort is high in some monogamous mating systems. Trivers' (1972) model predicts that high male investment in brood care should evolve only when males have a high certainty of paternity. For this study, we chose two woodpecker species: the great spotted woodpecker (Picoides major) and the middle spotted woodpecker (Picoides medius). Both species were socially monogamous despite a very high breeding density in the study area. We used DNA fingerprinting to determine whether these two species were also genetically monogamous. We found that in great spotted and middle spotted woodpeckers paternal effort was high. Multi-locus DNA-fingerprinting showed that its actual paternity was also very high. In P. major all 161 young from 36 broods and in P. medius all 61 young from 13 broods were sired by the male feeding at the nest hole. There were also no cases of intraspecific brood parasitism or quasi parasitism (P. major: 114 chicks from 24 broods; P.medius: 33 chicks from 8 broods). We further found no case of mate switching during the fertile period of the female. Great spotted and middle spotted woodpeckers are typical of a group of monogamous nonpasserine birds with high male investment in brood care having low frequencies of EPP. We did not find efficient paternity guards. High certainty of paternity may be explained by paternal care being essential for female reproductive success, as in many seabirds and birds of prey. Females rarely engage in extra-pair copulations probably because they are constrained by male care. Males in both species spend little effort in acquiring mates as well as in extrapair copulations. They expend their reproductive effort in defending territories and in parental care. Females compete intensely with members of their own sex for pair formation before the time of frequent copulation. Choosing and securing a high quality partner is the only possibility to achieve high reproductive success for both sexes.

scholarly journals Nest Attributes, Aggression, and Breeding Success of Gulls in Single and Mixed Species Subcolonies

The Condor ◽  
2006 ◽  
Vol 108 (1) ◽  
pp. 211-219 ◽  
Author(s):  
Julie C. Ellis ◽  
Thomas P. Good
Keyword(s):  
Reproductive Success ◽  
New England ◽  
Hatching Success ◽  
Relative Size ◽  
Single Species ◽  
Intraspecific Aggression ◽  
Costs And Benefits ◽  
Mixed Species ◽  
Aggressive Interactions ◽  
Herring Gulls

Abstract We investigated attributes of nests, aggressive interactions, and reproductive success in mixed and single species subcolonies of Great Black-backed Gulls (Larus marinus) and Herring Gulls (L. argentatus) on Appledore Island, Maine. Distances to the nearest neighboring nest were smaller for L. argentatus than L. marinus, with greatest distances between nests at edges of subcolonies in both species. More L. argentatus nests had natural screens (vegetation or rock >30 cm tall) adjacent to them than did L. marinus nests, but screen presence did not differ among nest positions within the colony. Clutch size did not differ between species; however, hatching success (number of chicks hatched per nest) was higher in L. argentatus than L. marinus. Fledging success (number of chicks fledged per nest) of L. marinus was greater at nests with heterospecific neighbors, whereas the opposite was true for L. argentatus. For both species, the frequency of aggressive interactions was lower at nests with L. argentatus neighbors. Overall, L. marinus nesting near L. argentatus experienced less aggression and greater reproductive success than those nesting among conspecifics, where intraspecific aggression was relatively high. L. argentatus nesting near L. marinus experienced more aggression and lower reproductive success than those nesting among conspecifics, where intraspecific aggression was relatively low. The costs and benefits of nesting in mixed species colonies may depend on the relative size and aggressiveness of the heterospecifics. Interactions with L. marinus in mixed species colonies may be contributing to the current declines of L. argentatus throughout New England.

scholarly journals MEASUREMENT OF FITNESS AND ITS COMPONENTS IN SIX LABORATORY STRAINS OF DROSOPHILA MELANOGASTER

Genetics ◽  
1984 ◽  
Vol 108 (1) ◽  
pp. 201-211
Author(s):  
Tsuneyuki Yamazaki
Keyword(s):  
Drosophila Melanogaster ◽  
Interspecific Competition ◽  
Population Size ◽  
Competitive Ability ◽  
Single Species ◽  
Phenotypic Correlation ◽  
Genotypic Correlation ◽  
The Real ◽  
Fitness Measures ◽  
Very High

ABSTRACT Six laboratory strains of Drosophila melanogaster were used to measure "net fitness" and its components by interspecific competition with D. hydei using 100 experimental populations. The "total competitive ability," an estimate of net fitness measured in these competition experiments, was tightly correlated with another measure of net fitness, the population size, in single-species experiments (phenotypic correlation rp = 0.675 and genotypic correlation rg = 0.997). Other components of fitness were also measured simultaneously, and the correlation with the net fitness was calculated. The very high correlation between two measurements of net fitness and lower correlations between net fitness and components of fitness suggests that these net fitness measures are more reliable estimates of the "real net fitness" than the components of fitness.

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