The comparative reproductive biology of three Leucospermum species (Proteaceae) in relation to fire responses and breeding system

1985 ◽  
Vol 33 (2) ◽  
pp. 139 ◽  
Author(s):  
B Lamont
Keyword(s):  
Reproductive Biology ◽  
Breeding System ◽  
Reproductive Effort ◽  
Seed Set ◽  
Sugar Concentration ◽  
Self Incompatibility ◽  
Nectar Volume ◽  
Cultivated Populations ◽  
Ecological Range

A study was made of both natural and cultivated populations of the resprouter after fire, Leucospermum cuneiforme, and two non-sprouters, L. cordifolium and L. erubescens. Measurements included florets per head, heads per plant (on an absolute and volume basis), nectar volume and sugar concentration, seeds per head and seed set following bagging to prevent access to pollinators. The results provided almost no support for the hypothesis that, in comparison with non-sprouters, resprouters minimize their reproductive effort in association with self-incompatibility. There was, however, some support for earlier proposals that the most self-compatible species (in this case, L. cuneiforme) have the widest ecological range, the greatest reproductive effort and highest percentage seed set.

Reproductive biology in two Genisteae (Papilionoideae) endemic of the western Mediterranean region: Cytisus striatus and Retama sphaerocarpa

1999 ◽  
Vol 77 (6) ◽  
pp. 809-820 ◽  
Author(s):  
Tomás Rodríguez-Riaño ◽  
Ana Ortega-Olivencia ◽  
Juan A Devesa
Keyword(s):  
Reproductive Biology ◽  
Inbreeding Depression ◽  
Mediterranean Region ◽  
Seed Set ◽  
Western Mediterranean ◽  
Self Incompatibility ◽  
Retama Sphaerocarpa ◽  
Early Action ◽  
Fruit And Seed Set ◽  
Cytisus Striatus

We studied the reproductive biology of two leguminous shrubs endemic of the western Mediterranean region Cytisus striatus (Hill) Rothm. and Retama sphaerocarpa (L.) Boiss. The former is polliniferous, and the latter is nectariferous, with maximum nectar production at the earliest hours of the morning. Germination of the pollen grains in the flowers of the two species occurs only after rupture of the stigmatic surface. It is also necessary in both cases that pollinators (mainly Apis mellifera) visit the flowers for fruit and seed set to occur. A study of the pollen-pistil interaction indicated that there exists prezygotic self-incompatibility in these two species, probably of the gametophytic type, but some self-pollen tubes escape this control and self-fertilize some ovules. However, after hand self-pollination, fruit and seed set is very low for both species. This suggests the existence of a postzygotic rejection mechanism, which could be due either to the existence of late-acting self-incompatibility or to an early action of inbreeding depression, although there are lines of evidence that seem to point to the second possibility. Hand cross-pollination led to an increased number of fruit and seeds per plant relative to the control plants, indicating that reproduction is pollen limited.Key words: late-acting self-incompatibility, prezygotic self-incompatibility, fruit set, seed set, inbreeding depression, Spain.

Reproductive biology and breeding system in Casuarina equisetifolia (Casuarinaceae) – implication for genetic improvement

2016 ◽  
Vol 64 (2) ◽  
pp. 120 ◽  
Author(s):  
Y. Zhang ◽  
C.L. Zhong ◽  
Q. Han ◽  
Q.B. Jiang ◽  
Y. Chen ◽  
...  
Keyword(s):  
Reproductive Biology ◽  
Breeding System ◽  
Genetic Improvement ◽  
Fruit Set ◽  
Seed Set ◽  
Pollen Limitation ◽  
Casuarina Equisetifolia ◽  
Open Pollination ◽  
Floral Longevity ◽  
Improvement Programs

Understanding the reproductive biology of plant species is essential for successful domestication and genetic improvement programs. Casuarina equisetifolia L. is an important plantation species in China and India but information on reproductive biology is limited. To address this issue, grafted ramets of C. equisetifolia were used to study floral biology, breeding system and progeny performance. The female floral longevity of C. equisetifolia reached 28.4 days under non-pollination conditions, which was significantly longer than that of supplementary pollination (5.5 days) and open pollination (12.2 days), implying successful pollination would accelerate senescence of female flowers. Higher fruit set (88.8%) and seed set (35.7%) under supplementary pollination were obtained, compared with 75.9% and 21.7%, respectively, under open pollination, although there were no fruit set and seed set under non-pollination conditions. Pollen limitation was evident based on pollen limitation index (0.39) in seedling plantations of C. equisetifolia. Selfed seedlings had low height and diameter growth in both nursery and field trials and markedly lower survival in field trial, indicating inbreeding depression. Microsatellite-based estimates of selfing rate of open pollinated, monoecious individuals was 42%, suggesting that monoecious C. equisetifolia individuals are self-compatible, and that the breeding system should be classified as facultative xenogamy.

scholarly journals Self-incompatibility in ryegrass VI. Self seed-set and incompatibility genotype in Lolium perenne L

Heredity ◽  
1983 ◽  
Vol 50 (2) ◽  
pp. 169-177 ◽  
Author(s):  
C H Fearon ◽  
M D Hayward ◽  
M J Lawrence
Keyword(s):  
Lolium Perenne ◽  
Seed Set ◽  
Self Incompatibility ◽  
Lolium Perenne L

Pollination ecology of Caryocar brasiliense (Caryocaraceae) in Central Brazil cerrado vegetation

1993 ◽  
Vol 9 (2) ◽  
pp. 199-211 ◽  
Author(s):  
Rogério Gribel ◽  
John D. Hay
Keyword(s):  
Breeding System ◽  
Fruit Set ◽  
Seed Set ◽  
Floral Biology ◽  
Cerrado Vegetation ◽  
Central Brazil ◽  
Glossophaga Soricina ◽  
Caryocar Brasiliense ◽  
Anoura Geoffroyi ◽  
Phyllostomus Discolor

ABSTRACTThe floral biology, breeding system and pollination of Caryocar brasiliense were studied in the cerrado vegetation of Central Brazil. The large, yellowish-cream, brush-like flowers are pollinated mainly by glossophagine bats (Glossophaga soricina and Anoura geoffroyi). Three non-glossophagine bats (Phyllostomus discolor, Vampyrops lineatus and Carollia perspicillata) and two short probosisced hawk moths (Erinyis ello and Pseudosphinx tetrio) may also act as occasional pollinators. Caryocar brasiliense is self-compatible although it sets significantly more fruits when crossed than when selfed. The natural fruit set (fruit/flower ratio) and seed set (seed/ovule ratio) are 3.1% and 1.0% respectively. Most of the fruits and seeds are formed through the action of the flower visitors, despite the fact that about 20% of the non-visited flowers receive self pollen on at least one stigma.

scholarly journals Flower mites decrease nectar availability in the rain-forest bromeliad Neoregelia johannis

2010 ◽  
Vol 26 (4) ◽  
pp. 373-379 ◽  
Author(s):  
Tadeu J. Guerra ◽  
Gustavo Q. Romero ◽  
Woodruff W. Benson
Keyword(s):  
Rain Forest ◽  
Sugar Content ◽  
Sugar Concentration ◽  
Production Rates ◽  
Nectar Production ◽  
Nectar Volume ◽  
Bombus Morio ◽  
Nectar Rewards ◽  
Flower Mites ◽  
Nectar Availability

Abstract:Nectarivorous flower mites can reduce the volume of nectar available to pollinators. The effects of the flower mite Proctolaelaps sp. on nectar availability in flowers of a melittophilous bromeliad Neoregelia johannis (Bromeliaceae) was evaluated in a coastal rain forest in south-eastern Brazil. In a randomized block experiment utilizing 18 flower pairs, one per bromeliad ramet, pollinators (Bombus morio) and mites were excluded, and then nectar volume, sugar concentration and sugar mass were quantified over the anthesis period. Mites significantly reduced nectar volume early in the morning (6h00–8h00), but not later (10h00–12h00). Mites decreased total volume of nectar available up to 22%. Sugar concentration in nectar was higher earlier in the morning, and decreased between 10h00–12h00. The pronounced consumption of nectar by mites during the period of higher sugar concentration reduced the total amount of sugar available to pollinators by 31%. This is the first study showing that flower mites decrease nectar rewards in a melittophilous plant. Because nectar volume by itself incompletely describes nectar production rates and the effects of nectar removal by flower mites on the availability of sugar, our study highlights the inclusion of sugar content in future studies assessing the effects of thieves on nectar production rates.

scholarly journals Interaction Between Ploidy, Breeding System, and Lineage Diversification

2019 ◽  
Author(s):  
Rosana Zenil-Ferguson ◽  
J. Gordon Burleigh ◽  
William A. Freyman ◽  
Boris Igić ◽  
Itay Mayrose ◽  
...  
Keyword(s):  
Breeding System ◽  
Whole Genome Duplication ◽  
Genome Duplication ◽  
Whole Genome ◽  
Self Incompatibility ◽  
Evolutionary Pathway ◽  
Diversification Rates ◽  
Extinction Rates ◽  
Biological Hierarchy ◽  
Lineage Diversification

AbstractIf particular traits consistently affect rates of speciation and extinction, broad macroevolutionary patterns can be understood as consequences of selection at high levels of the biological hierarchy. Identifying traits associated with diversification rate differences is complicated by the wide variety of characters under consideration and the statistical challenges of testing for associations from comparative phylogenetic data. Ploidy (diploid vs. polyploid states) and breeding system (self-incompatible vs. self-compatible states) have been repeatedly suggested as possible drivers of differential diversification. We investigate the connections of these traits, including their interaction, to speciation and extinction rates in Solanaceae. We show that the effect of ploidy on diversification can be largely explained by its correlation with breeding system and that additional unknown factors, alongside breeding system, influence diversification rates. These results are largely robust to allowing for diploidization. Finally, we find that the most common evolutionary pathway to polyploidy in Solanaceae occurs via direct breakdown of self-incompatibility by whole genome duplication, rather than indirectly via breakdown followed by polyploidization.

Onset and duration of stigma receptivity in Kunzea pomifera (Myrtaceae)

2006 ◽  
Vol 54 (6) ◽  
pp. 559 ◽  
Author(s):  
T. Page ◽  
G. M. Moore ◽  
J. Will ◽  
G. M. Halloran
Keyword(s):  
Pollen Tube ◽  
Reproductive Biology ◽  
Peroxidase Activity ◽  
Pollen Tube Growth ◽  
Seed Set ◽  
Stigma Receptivity ◽  
Controlled Pollination ◽  
Germinated Pollen ◽  
New Crop ◽  
Days After Anthesis

The onset and duration of stigma receptivity in K. pomifera was evaluated by observing stigma peroxidase activity, pollen-tube growth and seed set, following controlled pollination of flowers of different ages. Peroxidase activity was negligible from 1 day before to 4 days after anthesis, increasing to a peak of 65% at Day 13. The percentage of pistils bearing germinated pollen and ovaries exhibiting pollen-tube entry increased when pollen was applied to the stigma from the day before anthesis, to a maximum at Days 6 and 7 after anthesis, respectively, followed by a decline by Day 9. Under greenhouse conditions the optimum pollination period, measured as the level of set seed after pollination, ranged from 2 to 11 days after anthesis. The knowledge of this aspect of the species reproductive biology is of considerable value in controlled pollinations for its improvement as a new crop.

Sign in / Sign up

Export Citation Format

Share Document