Nectar Production and Pollination in Alstroemeria aurea: Responses to Level and Pattern of Flowering Shoot Defoliation

Oikos ◽  
1996 ◽  
Vol 76 (2) ◽  
pp. 312 ◽  
Author(s):  
Marcelo A. Aizen ◽  
Estela Raffaele
Keyword(s):  
Nectar Production ◽  
Alstroemeria Aurea

Influence of Phenotype, Season, and Time‐of‐day on Nectar Production in Cotton 1

Crop Science ◽  
1981 ◽  
Vol 21 (4) ◽  
pp. 507-511 ◽  
Author(s):  
Gordon D. Waller ◽  
F. D. Wilson ◽  
Joseph H. Martin
Keyword(s):  
Time Of Day ◽  
Nectar Production

scholarly journals Aging effect on nectar production in two clones of Asclepias syriaca

Oecologia ◽  
1983 ◽  
Vol 56 (1) ◽  
pp. 121-125 ◽  
Author(s):  
A. K. Southwick ◽  
E. E. Southwick
Keyword(s):  
Aging Effect ◽  
Asclepias Syriaca ◽  
Nectar Production

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.

Differential nectar production between male and female flowers in a wild cucurbit: Cucurbita maxima ssp. andreana (Cucurbitaceae)

2002 ◽  
Vol 80 (11) ◽  
pp. 1203-1208 ◽  
Author(s):  
Lorena Ashworth ◽  
Leonardo Galetto
Keyword(s):  
Reproductive Output ◽  
Male Flower ◽  
Female Flower ◽  
Cucurbita Maxima ◽  
Nectar Production ◽  
Male And Female ◽  
Nectar Sugar Composition ◽  
Nectar Sugar ◽  
Male Flowers ◽  
Female Flowers

In dioecious and monoecious plants that depend on animal vectors for reproduction, pollinators have to be attracted to male and female flowers for pollination to be effective. In the monoecious Cucurbita maxima ssp. andreana, male flowers are produced in greater quantity, are spatially more exposed to pollinators and offer pollen in addition to nectar as floral rewards. Nectar traits were compared between male and female flowers to determine any differences in the characteristics of the main reward offered to pollinators. Nectar chemical composition and sugar proportions were similar between flower types. Total nectar sugar production per female flower was threefold higher than per male flower, and nectar removal did not have any effect on total nectar production in both flower morphs. Pollinators reduced nectar standing crops to similar and very scarce amounts in both flower types. Results indicate indirectly that pollinators are consuming more nectar from female flowers, suggesting that the higher nectar production in female flowers may be a reward-based strategy to achieve the high female reproductive output observed in this species.Key words: Cucurbitaceae, Cucurbita maxima ssp. andreana, nectar production, nectar sugar composition, removal effects, standing crop.

Thinking honeyeater: nectar maps for the Northern Territory, Australia

2000 ◽  
Vol 6 (1) ◽  
pp. 61 ◽  
Author(s):  
John C. Z. Woinarski ◽  
Greg Connors ◽  
Don C. Franklin
Keyword(s):  
Northern Territory ◽  
Dry Season ◽  
Spatial And Temporal Variation ◽  
Wet Season ◽  
Nectar Production ◽  
The World ◽  
Eucalypt Forests ◽  
The Times ◽  
Species Specific ◽  
Nectar Availability

We create monthly maps of nectar availability for the 1.4 x 106 km2 jurisdiction of the Northern Territory, Australia. These are based on a combination of vegetation mapping and a series of indices of plant species specific nectar scoring. The maps reveal complex spatial and temporal variation in nectar availability, but most notably a greater nectar resource in the monsoon-influenced north than in the arid south, and a peak in nectar availability in the dry season. The latter is associated with the extensive tropical eucalypt forests (especially those co-dominated by Eucalyptus miniata and E. tetrodonta). In contrast, wet season nectar availability in these forests is limited, but riparian and swampland forests, typically dominated by Melaleuca species, provide rich but spatially restricted nectar resources. The extensive and rich nectar resources available in eucalypt forests in the dry season supplement the diets of many species which are not primarily nectarivorous. This resource helps shape the singularity of northern Australian eucalypt forests relative to other extensive forests elsewhere in the world. Nectarivores remain in the system through a combination of movements across a number of scales, habitat shifting, and diet shifting. The latter is aided by the peaking of invertebrate and fruit resources at the times of minimum nectar production; a shuffling in resource availability brought about by the extreme climatic seasonality.

Nectar Production in Anagyris foetida (Fabaceae): Two Types of Concentration in Flowers with Hanging Droplet

2007 ◽  
Vol 168 (5) ◽  
pp. 627-638 ◽  
Author(s):  
Francisco J. Valtueña ◽  
Ana Ortega‐Olivencia ◽  
Tomás Rodríguez‐Riaño
Keyword(s):  
Nectar Production

scholarly journals Nectar production of pear (Pyrus communis L.) cultivars

2000 ◽  
Vol 6 (3) ◽  
Author(s):  
P. Benedek ◽  
G. Kocsisné Molnár ◽  
J. Nyéki
Keyword(s):  
World Literature ◽  
Fruit Trees ◽  
Significant Negative Correlation ◽  
Sugar Concentration ◽  
Cold Weather ◽  
Nectar Production ◽  
Pyrus Communis L ◽  
The World ◽  
Pear Trees ◽  
Very High

Detailed studies were made on the nectar production of 44, 16 and 18 pear cultivars, respectively, in a cultivar collection of pear during three consecutive years with highly different weather in the blooming. Results clearly show that pear does not necessarily produce small amount of nectar as stated in the world literature. In fact, pear can produce extremely high amount of nectar sometimes much higher than other temperate zone fruit trees species but its nectar production is highly subjected to weather, first of all to air temperature. Low nectar production seems to be more frequent than high one and cold weather can prevent its nectar production at all. On the other hand, results corroborate to the earlier statements on the low sugar concentration of pear nectar. There is a highly significant negative correlation between the amount of nectar produced by pear flowers and its sugar concentration (r = -0.52, n = 291, p< 0.001 for 1996, r = -0.34, n = 197, p< 0.001 for 1998). Sugar concentration in individual flowers may be up, to 40% in exceptional cases but generally it is well below 20%. Very high figures for sugar concentration in pear nectar at the literature seem to be incomprehensible. In contrast of some earlier statement in the literature no real difference could be established in the nectar production of pear cultivars, based on much more measurements than in earlier studies. Very low sugar concentration in pear nectar can explain the fact that the overwhelming majority of honeybees are pollen gatherers at pear trees even in the case of exceptionally high nectar production.  

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