scholarly journals Flowering phenology influences seed production and outcrossing rate in populations of an alpine snowbed shrub, Phyllodoce aleutica: effects of pollinators and self-incompatibility

2009 ◽  
Vol 103 (9) ◽  
pp. 1385-1394 ◽  
Author(s):  
Yoshiaki Kameyama ◽  
Gaku Kudo
Keyword(s):  
Seed Production ◽  
Flowering Phenology ◽  
Outcrossing Rate ◽  
Self Incompatibility

Phenology and seed production in Chenopodium rubrum, Rumex maritimus, and Rumex palustris as related to photoperiod in river forelands

1992 ◽  
Vol 70 (2) ◽  
pp. 392-400 ◽  
Author(s):  
A. J. M. Van der Sman ◽  
C. W. P. M. Blom ◽  
H. M. Van de Steeg
Keyword(s):  
Life Cycle ◽  
Seed Production ◽  
Population Level ◽  
Flowering Phenology ◽  
Chenopodium Rubrum ◽  
Axillary Shoots ◽  
Critical Photoperiod ◽  
Number Of Leaves ◽  
Rumex Maritimus ◽  
Flooded Areas

Reproductive development in three species from irregularly flooded areas of river forelands was studied in relation to time of emergence. In Chenopodium rubrum, flowering was induced earlier in plants germinated in April–May than in later cohorts. However, the period of vegetative growth diminished and the life cycle was completed in a shorter time in later germinated plants. Seed number was reduced, but seed size as well as reproductive effort per plant increased in later cohorts. Plants of both Rumex species flowered after a certain number of leaves had developed and before a critical photoperiod had passed. In earlier cohorts, the main shoot and several axillary shoots elongated and flowered. Fewer axillary shoots flowered closer to the critical photoperiod, and this resulted in a reduced seed output in later cohorts. The critical photoperiod as well as the time needed for completion of the life cycle was longer in Rumex palustris than in Rumex maritimus. It is argued that in the riparian habitat, plants of both Rumex species are only occasionally able to complete their life cycle in one growing season. Survival of these species on the population level will rely more upon adaptations towards flooding during the established phase than is the case for C. rubrum. Key words: flowering phenology, photoperiod, seed production, Chenopodium rubrum, Rumex maritimus, Rumex palustris.

Hand-Tripped Flowers Promote Seed Production in Arachis lignosa, a Wild Peanut1

1990 ◽  
Vol 17 (1) ◽  
pp. 22-24 ◽  
Author(s):  
Donald J. Banks
Keyword(s):  
Seed Production ◽  
Growth Chamber ◽  
Self Incompatibility ◽  
Self Pollination ◽  
Reproductive Sterility ◽  
High Degree

Abstract In trials conducted in the greenhouse, growth chamber, and outdoors, no pegs or pods were produced when A. lignosa (Chod. et Hassl.) Krap. et Greg. nom. nud. plants were allowed to pollinate naturally. However, hand tripping flowers, especially in the greenhouse, resulted in significant increases in pod production. The results suggest that the high degree of reproductive sterility usually noted for A. lignosa in culture is due to pollination failure rather than to physiological self incompatibility. The somewhat truncated shape of the stigma and its elevated position relative to the anthers probably restricts natural self-pollination without the aid of pollinating vectors such as bees.

Seed mass, seed production, germination and seedling traits in two phenological types of Bidens pilosa (Asteraceae)

2004 ◽  
Vol 52 (5) ◽  
pp. 647 ◽  
Author(s):  
Diego E. Gurvich ◽  
Lucas Enrico ◽  
Guillermo Funes ◽  
Marcelo R. Zak
Keyword(s):  
Seed Production ◽  
Seedling Growth ◽  
Germination Rate ◽  
Seed Mass ◽  
Flowering Phenology ◽  
Early Type ◽  
Normal Type ◽  
Bidens Pilosa ◽  
Seedling Traits ◽  
Seed Sources

Bidens pilosa L. is a summer annual that shows a particular phenological pattern in the Córdoba mountains, Argentina. Some individuals start flowering 1 month after germination (early type), but most of the population starts flowering 4 months after germination (normal type). The aims of this study were to (1) analyse whether differences in flowering phenology affect seed mass and seed production, and (2) assess whether possible differences in seed traits of the two parental phenological types would affect germinability, germination rate, seedling growth and flowering phenology of offspring under laboratory conditions. The study showed that the numbers of seeds per capitulum and per plant were greater in the normal type than in the early type plants. This can be related to plant height, since in the field, normal-type plants are larger than early type plants. However, early type plants produced heavier seeds than normal-type plants. Germination rate was faster in the early type seeds, but total germination was higher in the normal ones. Seedling growth, in terms of height and the date of first flowering, did not differ between the phenological types of parental seed sources. Our results showed that differences in flowering phenology were associated with seed mass and seed production differences. Seed mass appears to be related to germination characteristics but not to seedling growth nor to flowering phenology of offspring.

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.

Flowering and seed production of sandalwood (Santalum album; Santalaceae) along environmental gradients in Gunung Sewu Geopark, Indonesia

1970 ◽  
Vol 8 (2) ◽  
Author(s):  
YENI W.N. RATNANINGRUM ◽  
ENY FARIDAH ◽  
SAPTO INDRIOKO ◽  
ATUS SYAHBUDIN
Keyword(s):  
Soil Moisture ◽  
Reproductive Success ◽  
Seed Production ◽  
Environmental Gradients ◽  
Flowering Phenology ◽  
Climatic Conditions ◽  
Dry Season ◽  
Temperature Sensitive ◽  
Santalum Album ◽  
Lower Altitude

Ratnaningrum YWN, Faridah E. Indroko S, Syahbudin A. 2016. Flowering and seed production of sandalwood (Santalum album; Santalaceae) along environmental gradients in Gunung Sewu Geopark, Indonesia. Nusantara Bioscience 8: 180-191. We observed flowering and seed production of sandalwood populations along environmental gradients in Gunung Sewu Geopark, Indonesia, in 2013 to 2014 flowering periods. We observe flowering phenology with regard to floral initiation, phases and periods, and measured Pollination Effectiveness and Reproductive Success, following modified methods of Owens et al and Ghazoul. Flowering and seed production varied with altitude and climatic conditions, and altered by changes in rainfall, temperature and soil moisture. Sites with lower altitude, lower rainfall, highest temperature, lowest relative humidity and lowest soil moisture flowered earlier and shorter. Flowering delayed and prolonged by increasing altitude, temperature and humidity. At all sites, flowering delayed and prolonged in rainy compared to dry season. Lower populations produced more flowers in rainy season, however, higher abortion resulted in a very low seed production. Dry season produced less flowers but higher reproductive success was achieved, resulting in more fruits. The lowest altitude performed highest reproductive outputs. More marked differences among sites were observed in the dry season. Flowering and seed production was also observed to be temperature sensitive. Both drop and increase on temperature resulted in the alteration of flowering frequency and reproductive outputs. Sandalwood in Gunung Sewu grow naturally in association with tropical moonsoon vegetation i.e. acacia, cajuputi, teak and mahogany. The conservation of this endangered species, particularly under wider range of landscapes, should be maintained with a different strategy according to the degree of plant sensitivity to environmental features.

scholarly journals Effect of GA3 and row ratio of restorer (R) and CMS lines (A) on different characters and seed production of BRRI Hybrid Dhan2

2013 ◽  
Vol 37 (4) ◽  
pp. 665-676 ◽  
Author(s):  
MH Rahman ◽  
MM Khatun ◽  
MSR Khan ◽  
MAK Mian ◽  
MG Rasul
Keyword(s):  
Seed Production ◽  
Seed Yield ◽  
Yield Components ◽  
Outcrossing Rate ◽  
Grain Weight ◽  
Growth And Yield ◽  
Four Levels ◽  
1000 Grain Weight ◽  
Different Doses ◽  
Research Institute

An experiment was conducted at the experimental farm of Bangladesh Rice Research Institute (BRRI), Gazipur, during November to May 2009-10 to study the effect of GA3and row ratio of restorer and CMS lines on different characters and F1 seed production of BRRI hybrid dhan2. The treatments were of four levels of GA3 viz., (i) control, (ii) 150 g/ha, (iii) 250 g/ha, and (iv) 350 g/ha and five row ratios (R:A) viz., (i) 2:8, (ii) 2:10, (iii) 2:12, (iv) 2:14, and (v) 2:16. Different doses of GA3 ignificantly influenced growth and yield components of rice except total tillers/hill and 1000-grain weight. The highest F1 seed yield (2.34 t/ha) of BRRI hybrid dhan2 was obtained with an application of GA3 @ 250 g/ha which enhanced the maximum number of effective tillers, the highest number of grains/panicle, panicle exsertion rate and outcrossing rate. The lowest seed yield (1.10 t/ha) was produced without application of GA3 i.e., control. The row ratio of 2:12 and 2:8 produced the highest (2.05 t/ha) and the lowest (1.63 t/ha) F1seed yield, respectively. The interaction between GA3 and row ratio of restorer and CMS lines was significant for F1 seed yield. The highest F1 seed yield (2.90 t/ha) was obtained with the application of GA3 @ 250 g/ha at the row ratio of 2:12 (R: A). The lowest seed yield (0.95 t/ha) was recorded without application of GA3 (control) at row ratios of 2:16. DOI: http://dx.doi.org/10.3329/bjar.v37i4.14391 Bangladesh J. Agril. Res. 37(4): 665-676, December 2012

scholarly journals Pollination and late-acting self-incompatibility in Cyrtanthus breviflorus (Amaryllidaceae): implications for seed production

2010 ◽  
Vol 106 (4) ◽  
pp. 547-555 ◽  
Author(s):  
Glenda Vaughton ◽  
Mike Ramsey ◽  
Steven D. Johnson
Keyword(s):  
Seed Production ◽  
Self Incompatibility

scholarly journals When spring ephemerals fail to meet pollinators: mechanism of phenological mismatch and its impact on plant reproduction

2019 ◽  
Vol 286 (1904) ◽  
pp. 20190573 ◽  
Author(s):  
Gaku Kudo ◽  
Elisabeth J. Cooper
Keyword(s):  
Seed Production ◽  
Plant Reproduction ◽  
Flowering Phenology ◽  
Spring Phenology ◽  
Snow Removal ◽  
Pollination Success ◽  
Spring Ephemerals ◽  
Degree Day ◽  
Spring Ephemeral ◽  
Phenological Mismatch

The flowering phenology of early-blooming plants is largely determined by snowmelt timing in high-latitude and high-altitude ecosystems. When the synchrony of flowering and pollinator emergence is disturbed by climate change, seed production may be restricted due to insufficient pollination success. We revealed the mechanism of phenological mismatch between a spring ephemeral ( Corydalis ambigua ) and its pollinator (overwintered bumblebees), and its impact on plant reproduction, based on 19 years of monitoring and a snow removal experiment in a cool-temperate forest in northern Japan. Early snowmelt increased the risk of phenological mismatch under natural conditions. Seed production was limited by pollination success over the 3 years of the pollination experiment and decreased when flowering occurred prior to bee emergence. Similar trends were detected on modification of flowering phenology through snow removal. Following snowmelt, the length of the pre-flowering period strongly depended on the ambient surface temperature, ranging from 4 days (at greater than 7°C) to 26 days (at 2.5°C). Flowering onset was explained with an accumulated surface degree-day model. Bumblebees emerged when soil temperature reached 6°C, which was predictable by an accumulated soil degree-day model, although foraging activity after emergence might depend on air temperature. These results indicate that phenological mismatch tends to occur when snow melts early but subsequent soil warming progresses slowly. Thus, modification of the snowmelt regime could be a major driver disturbing spring phenology in northern ecosystems.

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