The beneficial effect of ants on the reproductive success of Dyckia floribunda (Bromeliaceae), an extrafloral nectary plant

2003 ◽  
Vol 81 (1) ◽  
pp. 24-27 ◽  
Author(s):  
José L Vesprini ◽  
Leonardo Galetto ◽  
Gabriel Bernardello
Keyword(s):  
Seed Production ◽  
Reproductive Output ◽  
Fruit Set ◽  
Seed Set ◽  
Reproductive Organs ◽  
Extrafloral Nectaries ◽  
Perennial Herb ◽  
Seed Number ◽  
Total Seed ◽  
Mutualistic Association

Dyckia floribunda is a perennial herb from the Argentinian Chaco with extrafloral nectaries. Ants visited these nectaries while patrolling inflorescences and infructescences. We anticipated that ants attracted to extrafloral nectaries might protect the reproductive organs, increasing plant reproductive output. To evaluate the possibility of mutualism between D. floribunda and ant visitors, we determined whether ant-accessible plants showed a higher seed production than ant-excluded plants. Experimental fieldwork suggested a decrease in fruit set of ant-excluded plants compared with ant-accessible plants but the seed number per fruit was not affected by ant exclusion. Thus, total seed number per plant was highly reduced in treated spikes. Analyses of covariance confirmed these trends, indicating that total seed production per plant was strongly affected by ant exclusion. This study marks the first experimental report of this mutualistic association in Bromeliaceae.Key words: ant–plant interaction, Bromeliaceae, Chaco, Dyckia floribunda, fruit set, seed set, mutualism.

Spatial variation in seed production among and within sites and within individuals of Thalictrum thalictroides (Ranunculaceae)

1986 ◽  
Vol 64 (3) ◽  
pp. 658-667 ◽  
Author(s):  
Anne E. Lubbers
Keyword(s):  
Spatial Variation ◽  
Seed Set ◽  
Perennial Herb ◽  
Seed Number ◽  
Normal Distributions ◽  
Ovule Number ◽  
One Year ◽  
Log Normal ◽  
Total Seed ◽  
Number Of Seeds

Spatial variation in seed and ovule numbers and percent seed set is described for three populations of the perennial herb Thalictrum thalictroides. Total ovule number of an individual was positively correlated with its seed number, but correlations between ovule number and percent seed set were negative or nonsignificant. Ovule and seed numbers, and to some extent percent seed set, varied among flower positions and inflorescences within plants. Within sites, log-normal distributions of total seed number indicate that a few individuals contributed a large number of seeds relative to the rest of the population. At two sites high values of percent seed set suggest that factors that determine ovule number can be at least as critical to variation in seed number as other factors acting later on. Quadrat reproductive means were not correlated from one year to the next, implying that the relative favorability of certain quadrats is not consistent among years. Sites varied in their reproductive means as well as in their frequency distribution of percent seed set, indicating that the importance of initial ovule number to final seed number per plant not only varies among species as is commonly observed but within as well.

Increased seed production of subterranean clover pastures in response to fertilizers supplying calcium

1974 ◽  
Vol 14 (71) ◽  
pp. 749 ◽  
Author(s):  
PG Ozanne ◽  
KMW Howes
Keyword(s):  
Seed Production ◽  
Calcium Concentration ◽  
Field Experiments ◽  
Seed Set ◽  
Subterranean Clover ◽  
Trifolium Subterraneum ◽  
Unit Weight ◽  
Gypsum Plaster ◽  
Total Seed ◽  
Seed Yields

The effects of four common fertilizers containing calcium on seed production in subterranean clover (Trifolium subterraneum) were measured at six locations over five years in a total of fifteen field experiments. Calcium as a sulphate, carbonate or phosphate salt was applied to subterranean clover pastures either at the start of the growing season (autumn) or at flowering (spring). Gypsum, plaster of Paris, or lime gave large increases in seed yield per unit area and also per unit weight of tops. Spring applications of superphosphate increased seed yields in only two out of four experiments. Gypsum applied in spring at 200-500 kg ha-1 was as effective as 2,000 kg ha-1 of lime applied in autumn. Applications of lime in spring were much less effective. Increased seed yields were due to increases in burr yield, seed number per burr, and mean weight per seed. They were usually accompanied by increases in calcium concentration in the seed. Responses in seed production to calcium applications were obtained in all three sub-species of Trifolium subterraneum. In two experiments, newly sown on a soil type on which subterranean clover regeneration and persistence is commonly very poor, applied calcium doubled or quadrupled seed set. In 13 experiments using soils on which subterranean clover had persisted as the major component of the pasture for several years, calcium in the year of application increased the total seed bank by 6 to 31 per cent, and the current seed set by a greater amount.

Texas Panicum (Panicum texanum) Growth as Affected by Irrigation Management and Planting Date

Weed Science ◽  
1990 ◽  
Vol 38 (4-5) ◽  
pp. 374-378 ◽  
Author(s):  
Jill Schroeder ◽  
Clyde C. Dowler ◽  
James R. Stansell
Keyword(s):  
Seed Production ◽  
Irrigation Management ◽  
Dry Weight ◽  
Planting Date ◽  
Soil Matric Potential ◽  
Seed Number ◽  
Matric Potential ◽  
Total Seed

The effect of soil matric potential from −0.02 to <–1.5 MPa on Texas panicum growth in drainage lysimeters covered by an automatic rainfall shelter was measured in 1984, 1985, and 1986. Rate of tiller production was faster for plants established in April than June in 1984 and 1985, but not 1986. In 1985 and 1986, dry weight was greater, but total seed production was less for plants established in April than June. Irrigation when the soil matric potential was −0.02, −0.075, or −1.5 MPa did not affect rate of tiller production in 1984. Irrigation when the soil matric potential was −1.5 MPa decreased dry weight of plants but increased seed number per panicle compared to irrigation when the soil matric potential was −0.02 MPa in 1985 and 1986. Plants grown in lysimeters irrigated at soil matric potential <–1.5 MPa in 1985 and 1986 did not wilt at 8:00 a.m.; therefore, they were not watered after establishment. These nonirrigated plants averaged 0.9 and 0.4 kg dry weight and produced 92 200 and 16 100 seeds in 1985 and 1986, respectively.

Pre-dispersal seed predation by the weevils Trichapion rostrum and Tychius sordidus limits reproductive output of Baptisia alba (Fabaceae)

Botany ◽  
2017 ◽  
Vol 95 (8) ◽  
pp. 809-817 ◽  
Author(s):  
Ashley M. Hembrough ◽  
Victoria A. Borowicz
Keyword(s):  
Seed Production ◽  
Seed Predation ◽  
Reproductive Output ◽  
Pollen Limitation ◽  
Reproductive Potential ◽  
Prairie Restoration ◽  
Seed Number ◽  
Nutrient Supplementation ◽  
Perennial Legume ◽  
Herbaceous Perennial

Baptisia alba (L.) Vent., an herbaceous, perennial legume, produces more flowers than will mature into pods. Single-year experiments on two reconstructed prairies tested the hypothesis that reproductive potential of B. alba depends on nutrients, but pollen limitation and pre-dispersal seed predation by weevils reduce final production. Ramets were assigned one of four treatments that were combinations of fertilizer (none/70 g fertilizer twice) and insect barrier (none/application of Tanglefoot). Within inflorescences, flowers were naturally pollinated or supplemented with pollen. Fertilizer produced no effects, suggesting that B. alba are unresponsive within a season to nutrient supplementation. Pollen supplementation increased pod initiation at the two sites by 6.7% and 2.3%, respectively, but did not affect the proportion of initiated pods that matured or seed number within pods. Where Tychius sordidus occurred, only 67 pods matured on 19 ramets and only four seeds survived. Where only Trichapion rostrum was present, insect barrier increased pod maturation almost three-fold, but did not affect seed number within pods. Barrier treatment increased the reproductive output of entire ramets by increasing seed production, from 3.6 seeds·ramet−1 to 60.5 seeds·ramet−1. Prairie restoration frequently uses fruit collected from other populations. Managers should be careful to avoid the unintended introduction of voracious seed predators.

scholarly journals Floral herbivory does not reduce pollination-mediated fitness in shelter rewarding Royal Irises

2017 ◽  
Author(s):  
Mahua Ghara ◽  
Christina Ewerhardy ◽  
Gil Yardeni ◽  
Mor Matzliach ◽  
Yuval Sapir
Keyword(s):  
Fruit Set ◽  
Seed Set ◽  
Pollen Grains ◽  
Reproductive Organs ◽  
Pollen Grain ◽  
Lower Number ◽  
Pollen Deposition ◽  
Pollination Services ◽  
Pollinator Visitation ◽  
Direct Damage

ABSTRACTFlorivory, the damage to flowers by herbivores can affect fitness both directly and indirectly. Flowers consumed by florivores may fail to produce fruit or produce lower seed set because of direct damage to reproductive organs. In addition, eaten flowers are less attractive to pollinators because of reduced or modified advertisement, which reduces pollination services. While observational data are abundant, experimental evidence is scarce and results are contrasting. We tested experimentally the effect of florivory on both pollinator visitation and reproductive success in three species of the Royal Irises, which have large flowers that are attractive to pollinators, and potentially also for florivores. We hypothesized that florivory will reduce pollen deposition due to reduced attractiveness to pollinators, while fruit set and seed set will depend on the extent of florivory. We performed artificial florivory in two experiments over two years. In the first experiment, each of the three floral units of a single Iris flower was subject to either low or high artificial florivory, or left un-touched as control. We counted the number of pollen grains deposited on each of the three stigmas as a measure of pollinator visitation. In the second experiment, three flowers of the same plant received low, high, or no artificial florivory and were further recorded for fruit and seed production. In 2016, high artificial florivory revealed lower number of pollen grains on stigmas of Iris atropurpurea, but in 2017 there was no difference. Similarly, number of pollen grains in high artificial was lower than low florivory in 2017 in I. petrana. No significant effect of florivory was found on pollen grain deposition, fruit set or seed set. The results remained consistent across species and across years. The results undermine the assumption that flower herbivory is necessarily antagonistic interaction and suggests that florivores may not be strong selection agents on floral reproductive biology in the Oncocyclus irises.

scholarly journals Efficiency of Buzzing Bees in Fruit Set and Seed Set ofSolanum violaceumin Sri Lanka

2012 ◽  
Vol 2012 ◽  
pp. 1-7 ◽  
Author(s):  
R. W. M. U. M. Wanigasekara ◽  
W. A. I. P. Karunaratne
Keyword(s):  
Sri Lanka ◽  
Seed Production ◽  
Fruit Set ◽  
Seed Set ◽  
Handling Time ◽  
Apis Dorsata ◽  
Buzz Pollination ◽  
Vegetable Crop ◽  
Flower Visiting ◽  
Plant Pollinator

Plant-pollinator interactions are often considered as tightly coevolved, mutualistic relationships. The present study aimed at determining the flower visiting bees of the vegetable crop,Solanum violaceum, and the efficiency of buzz pollination by bees on fruit and seed production in Sri Lanka. Seven bee species:Hoplonomia westwoodi,Amegilla comberi,Patellapis kaluterae,Xylocopa tenuiscapa,Apis dorsata,Trigona iridipennis, andCeratina hieroglyphicavisited the flowers ofS. violaceum, and the first four species were buzzing bees. Buzzing bees were the first to visitSolanumflowers and were followed by nonbuzzing bees. Handling time ofH. westwoodiandP. kaluteraevaried with the availability of pollen in anthers that deplete with the age of flower and stayed longer at new flowers than at old flowers. Handling time of the larger buzzing bee,H. westwoodi, was higher than that of the smallerP. kaluterae. The fruit set, seed set, and seed germinability in flowers visited by buzzing bees were significantly higher than those of the flowers bagged to exclude pollinators.

scholarly journals Pollination Requirements of Three Highbush Blueberry (Vaccinium corymbosum L.) Cultivars

1997 ◽  
Vol 122 (6) ◽  
pp. 891-896 ◽  
Author(s):  
Kenna E. MacKenzie
Keyword(s):  
Seed Coat ◽  
Fruit Set ◽  
Vaccinium Corymbosum ◽  
Harvest Date ◽  
Highbush Blueberry ◽  
Seed Number ◽  
Berry Size ◽  
Low Levels ◽  
Viable Seeds ◽  
Total Seed

The effects of pollination treatments on fruit set and five berry characteristics [mass, diameter, number of apparently viable seeds (well-developed, plump with dark seed coat), total seed number (includes apparently viable and partially developed seeds), and harvest date] were examined on three highbush blueberry cultivars. Pollination treatments included unpollinated, open pollinated, emasculated, and three hand pollinations that used pollen from the same flower, from the same cultivar, or from a different cultivar. Berries matured earliest and were smallest with the most apparently viable seeds in `Northland', `Patriot' had the greatest fruit set and smallest seed number, and `Bluecrop' matured the latest. Fruit set was greater, berry size larger, seed number smaller, and maturation later in 1990 than 1991. For all three cultivars, berries were generally smallest, latest maturing, and had the fewest seeds when pollination was prevented and were largest with the most seeds and earliest maturing in open visitation. Emasculation resulted in berries similar to those from unpollinated flowers. For berry characteristics, cross-pollination was of benefit for `Patriot' and possibly `Northland' but not `Bluecrop'. Thus, commercial highbush blueberry planting designs must be based on the pollination requirements of the particular cultivar. `Northland' berries almost always had seeds, while `Patriot' showed high levels and `Bluecrop' low levels of parthenocarpy.

Pollination and seed production in five boreal species of Vaccnium and Andromeda (Ericaceae)

1996 ◽  
Vol 74 (9) ◽  
pp. 1363-1368 ◽  
Author(s):  
Heléne Fröborg
Keyword(s):  
Seed Production ◽  
Fruit Set ◽  
Seed Set ◽  
Coniferous Forest ◽  
Natural Habitats ◽  
Vaccinium Uliginosum ◽  
Self Pollination ◽  
Hand Pollination ◽  
Understory Shrubs ◽  
Fruit And Seed Set

Using experimental manipulations, I examined if pollen quality affected fruit and seed production in five ericaceous understory shrubs in a coniferous forest in central Sweden. Flowers of Vaccinium myrtillus L., Vaccinium uliginosum L., Vaccinium vitis-idaea L., Vaccinium oxycoccos Gil., and Andromeda polifolia L. were (treatment 1) open-pollinated, (treatment 2) bagged without further treatment, (treatment 3) bagged and self-pollinated, (treatment 4) cross-pollinated with pollen from neighbouring plants, or (treatment 5) supplied with pollen from distant plants. Finally, flowers were (treatment 6) open-pollinated with a supply of extra pollen of distant origin. To investigate pollen or resource limitations to fruit and seed production, V. vitis-idaea was subjected to partial flower removal followed by open- and hand-pollination. Fruit and seed set were estimated for each treatment. The main conclusion is that natural levels of outcrossing are sufficiently high for full seed production and that the availability of pollen is not limiting in natural habitats. There were significant reductions in fruit and seed set after self-pollination in V. myrtillus. Fruit set was reduced in V. vitis-idaea, and V. uliginosum failed to set fruit after self-pollination. Self-pollination caused a decreased seed set in A. polifolia. There was no significant variation across treatments in V. oxycoccos. Since fruits tend to develop regardless of seed number, resources are likely to limit seed production in species with costly fruits. Keywords: self-fertility, pollination, Vaccinium, fruit set, seed set.

scholarly journals 530 Fruitfulness of Evergreen vs. Deciduous Southern Highbush Blueberry after Cross-, Self-, and No Pollination

HortScience ◽  
1999 ◽  
Vol 34 (3) ◽  
pp. 537B-537
Author(s):  
Ingrith D. Martinez ◽  
P.M. Lyrene
Keyword(s):  
Seed Production ◽  
Fruit Set ◽  
Fruit Size ◽  
Management Systems ◽  
Highbush Blueberry ◽  
Seed Number ◽  
Dormant Period ◽  
Mature Leaves ◽  
Hand Pollination ◽  
Southern Highbush

Fruit set, fruit size, and seed production after hand pollination in a greenhouse were compared for southern highbush blueberry managed in two ways: a) 69 clones were allowed to go dormant and lose their leaves in the field before being dug and subjected to 1000 hours at 5 °C and b) 26 clones were kept growing in a greenhouse through fall and winter without leaf loss and without chilling, to induce flowering on plants that had mature leaves. On each plant in both management systems, some flowers were self-pollinated, some were cross-pollinated, and others had the styles removed before anthesis to prevent pollination. For >1000 flowers per pollination treatment on the deciduous plants, fruit set averaged 1% for no pollination, 46% for self-pollination, and 76% for cross-pollination. The corresponding values for the evergreen plants were 23%, 59%, and 81%. Parthenocarpic berries averaged 0.37 g/berry for deciduous plants and 1.01 g for evergreen plants. Both crossed and selfed berry weights averaged slightly higher for the evergreen plants than for the deciduous plants, but seed number per berry was much lower for the evergreen plants (12 seeds in crossed berries and four seeds in selfed berries) compared to deciduous plants (37 and 8). Southern highbush blueberry plants that flower without going dormant appear to have much higher parthenocarpic capabilities than those that flower after a dormant period.

Physiology of growth and seed production in Lupinus angustifolius L. I. Effects on pod and seed set of controlled short duration high temperatures at flowering

1984 ◽  
Vol 35 (4) ◽  
pp. 493 ◽  
Author(s):  
RW Downes ◽  
JS Gladstones
Keyword(s):  
Seed Production ◽  
Temperature Stress ◽  
High Temperatures ◽  
Short Duration ◽  
Seed Set ◽  
Lupinus Angustifolius ◽  
Seed Number ◽  
Ovule Abortion ◽  
Time Control ◽  
Hormone Effects

Plants of Lupinus angustifolius cv. Unicrop, with branches excised to eliminate competition between branches and the primary inflorescence, were exposed to three temperature treatments: 33/28, 33/13 and 18/28�C. Each treatment continued for 1, 3 or 5 days, and was begun as flowers were starting to open, or 5 days before, or 10 days after that time. Control plants remained at 18/13�C throughout. Stress due to high day temperatures before flowering prevented early flowers from developing pods, but later flowers were able to compensate. Temperature stress as flowering began substantially reduced numbers of seed-containing pods, and little compensation was observed, either in later pod set or in seed number per pod. After flowering, high day temperatures did not affect the most developed pods, but ovule abortion reduced seed production in the less developed pods. These findings are discussed in relation to assimilate availability and hormone effects, and the adaptability of the narrow-leafed lupin plant is discussed in view of environmental restraints. Breeding implications are briefly considered.

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