An experimental study of the pollination biology of the perennial halophyte Frankenia pauciflora var. gunnii (Frankeniaceae) in a South Australian salt marsh

2009 ◽  
Vol 57 (1) ◽  
pp. 31 ◽  
Author(s):  
Duncan A. Mackay ◽  
Molly A. Whalen

Relatively little is known about the pollination biology or breeding systems of entomophilous plant species in salt-marsh habitats. In the present study, the pollination biology of the perennial halophyte Frankenia pauciflora DC. var. gunnii Summerh. (Frankeniaceae) was investigated in a salt marsh near Goolwa, South Australia. The flowering peak of this species occurs in summer and flowers are visited by a diverse array of insects in the Diptera, Hymenoptera and Lepidoptera. An experiment was performed to test for the presence of pollen limitation in the field. Flowers to which outcross pollen was added produced significantly more fruits and significantly more seeds per fruit than did unmanipulated control flowers. Average seed weight per fruit did not differ significantly between control and pollen-addition flowers. In glasshouse experiments, flowers to which cross-pollen was added produced significantly more fruit than did flowers to which self-pollen was added, suggesting the presence of a facultatively xenogamous breeding system.

2010 ◽  
Vol 58 (2) ◽  
pp. 115 ◽  
Author(s):  
Nan Jiang ◽  
Wen-Bin Yu ◽  
Hong-Zhe Li ◽  
Kai-Yun Guan

Flowers of Clematis display showy corollas and diversified shapes. This diversity motivates study of adaptive evolution of flower–pollinator interactions and the functional association between floral traits and plant mating strategies. An integrative study was undertaken, which focused on pollination and reproductive biology of three species representing all three floral types of Clematis. Floral traits were measured, and pollinator assemblages were observed in the field. Bagging, hand-pollination and removal treatments were used to examine breeding systems. The inbreeding depression and pollen limitation were estimated by fruit-set and seed production obtained from pollination treatments. Their floral traits are distinctly different, but are highly associated with pollination syndrome and breeding system. Among them, Clematis akebioides and C. rehderiana may be facultative autogamy (the former was delayed selfing, and the later competing selfing), and C. chrysocoma may be nearly obligate outcrossing. These conclusions are reflected in their stamen-pistil ratios. The levels of inbreeding depression are negatively associated with autonomous self-pollination. Evolution of self-pollination in C. akebioides and C. rehderiana, and pollen limitation in reproduction of the three Clematis species are discussed. This present study, integrating with previous results, will help us to comprehensively recognise and understand the pollination system and reproductive characteristics of Clematis.


Oryx ◽  
2017 ◽  
Vol 52 (3) ◽  
pp. 479-488 ◽  
Author(s):  
Ann K. Sakai ◽  
Stephen G. Weller ◽  
Weigang Yang ◽  
Susan Ching Harbin ◽  
Talia Portner ◽  
...  

AbstractWe report on how a long-term study of the reproductive biology of the Critically Endangered Schiedea adamantis (Caryophyllaceae), one of Hawai‘i's rarest plant species, was leveraged for conservation purposes. Our major goals were to provide seeds with the greatest genetic variation possible for reintroduction and to ensure that both female and hermaphroditic plants of this wind-pollinated species were reintroduced in a manner that maximized both outcrossing and seed production. Schiedea adamantis was one of the first Hawaiian plant species listed under the Endangered Species Act (USA). The species has been studied intensively to test hypotheses addressing the evolution of breeding systems. Information on outcrossing levels and the extent of inbreeding depression was integrated into ongoing reintroduction efforts. Population size peaked in 1994, when 267 flowering individuals were found on Lē‘ahi (Diamond Head Crater). By 2016 only 17 flowering individuals were present, with drought and invasive species being possible causes of this decline. Reintroduction attempts in 1998 using genetically diverse seeds were unsuccessful because of drought and a lack of sufficient supplemental irrigation. Additional reintroduction attempts in 2012 and 2014 were more successful because of increased supplemental irrigation. Plants used in reintroductions represent genotypes long since absent in the natural population, and may contain the genetic variability essential for evolutionary responses to climate change and the spread of invasive species. The destruction of many plants reintroduced in 2015 and 2016 by a fire in March 2016 highlights the need for additional restoration areas at Lē‘ahi and elsewhere, and storage of seeds for future use.


2012 ◽  
Vol 110 (8) ◽  
pp. 1607-1621 ◽  
Author(s):  
Agustin Sanguinetti ◽  
Cristiano Roberto Buzatto ◽  
Marcelo Pedron ◽  
Kevin L. Davies ◽  
Pedro Maria de Abreu Ferreira ◽  
...  

1992 ◽  
Vol 40 (1) ◽  
pp. 13 ◽  
Author(s):  
WG Breed ◽  
M Adams

This study was carried out as part of a broader investigation into the factors that determine interspecific variation in testis size amongst conilurine rodents. The hypothesis proposed is that the huge differences in absolute and relative testis size between the spinifex hopping mouse (Notomys alexis) and the plains rat (Pseudomys australis) relate to differences in breeding system. One aspect of a species' breeding system, the capacity for multiple paternity, was assessed under laboratory conditions for each species. Allozyme markers were used to set up appropriate trios consisting of one female cohabiting with two mates of different genotypes and to assess the paternity of the resultant pups that were born. Multiple paternity within a single litter was not recorded for hopping mice but was observed occasionally in plains rats, a result consistent with the hypothesis under test.


Hoehnea ◽  
2018 ◽  
Vol 45 (1) ◽  
pp. 93-102 ◽  
Author(s):  
Adriana de Oliveira Fidalgo ◽  
Débora Marcouizos Guimarães ◽  
Gabriela Toledo Caldiron ◽  
José Marcos Barbosa

ABSTRACT The present study evaluates and compares the phenology, pollination biology and breeding systems of Chamaecrista desvauxii (Collad.) Killip.and Clitoria laurifolia Poir. in a coastal plain degraded by sand mining in São Paulo State, Brazil, from January 2006 to May 2008. Flowering and fruiting events occurred in the warm and rainy season. Both species are self-compatible but only C. desvauxii was pollinator-dependent to set fruits. A small group of bees, comprising Eufrisea sp., Eulaema (Apeulaema) cingulata and Bombus morio, accessed the male and female floral structures and moved among individuals resulting in cross-pollinations. However, only B. morio was a frequent visitor and an effective pollinator. Although recruitment and survival of population in the study area are high for both species, we observed lower abundance and richness of visitors suggesting the possible lack of pollinators and pollen limitation.


1959 ◽  
Vol 57 (4) ◽  
pp. 386-402 ◽  
Author(s):  
A. A. Tuffery

Two units, within a mouse-breeding colony, with different breeding systems, have been compared from the point of view of general healthiness of the breeding stock. In one unit the monogamous-pair system, involving post-partum oestrus mating, was employed and in the other the harem system, with isolation of the pregnant females for each litter-down until after the post-partum oestrus. The two units were housed separately and had different staffs. The monogamous-pair unit was accommodated in four small rooms not directly connected; the harem unit in two larger connecting rooms. The methods of cageing, bedding, feeding, watering, care, culling and subsequent procedures were identical for both units and the same system of recording individual detailed information relating to health and breeding was followed for the two units. The size of the two populations studied was 1198 and 1024, respectively, the larger number belonging to the harem unit in which the mice were retained for a significantly longer period. These mice were moved more frequently and handled much more often.Apart from a small outbreak of Tyzzer's disease (in the harem-bred unit) and sporadic cases in both units spread over the whole period of the survey—some 3–4 years—the general health of the two units was good. There were no cases of salmonella infection, mousepox, pasteurellosis or other serious infections. Throughout the period both units maintained a high standard of productivity and there was no evidence that the mating of the monogamous pairs at the post-partum oestrus led to any weakness or ill health. As would be expected, however, the losses from death and culling were greater among the females in both units.The health record of the monogamous-pair bred unit was consistently higher than that of the harem-bred unit. There were more cases of Tyzzer's disease in the harem-bred mice and more evidence generally of ill health in this unit. Infertility was three times greater with the harem-bred mice as compared with those in the monogamous-pair unit.Details of the two systems are discussed and although the records maintained for the two may not be strictly comparable it is concluded that, under the conditions obtaining, the monogamous-pair breeding system yielded a healthier colony of mice than the harem breeding system.I should like to thank Dr J. S. Patterson and Mr R. Cook for placing many of their records at my disposal, Mr S. Peto and his staff for carrying out much of the tedious compilation of data, and Dr D. W. Henderson, F.R.S., for affording me facilities for this work. To these I am especially grateful for their interest, advice and assistance.


1990 ◽  
Vol 38 (2) ◽  
pp. 217 ◽  
Author(s):  
AJ Willis ◽  
JE Ash

The breeding systems of Stylidiurn grarninifolium and S. producturn (= S. grarninifoliurn var. caulescens) were studied by observing the phenology of individual flowers and inflorescences, and relating the data to a series of pollination experiments within and between the species. Inter-specific pollinations yielded similar levels of seed-set to crosses within the species indicating a close relationship between the taxa. Self-pollination of either species is uncommon; however, when it occurs, the majority of selfed ovules are aborted post-zygotically, probably by a system of recessive lethals, as there is no indication of an incompatibility system. It is concluded that the breeding systems of S. grarninifoliurn and S. productum, two of the few eastern Australian species, are similar to those of many Stylidiurn species from the south-west, casting doubt upon hypotheses that the breeding system has led to high rates of speciation in the south-west.


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