Nectar Secretion, Reabsorption, and Sugar Composition in Male and Female Flowers of Cucurbita pepo

2001 ◽  
Vol 162 (2) ◽  
pp. 353-358 ◽  
Author(s):  
Massimo Nepi ◽  
Massimo Guarnieri ◽  
Ettore Pacini

2007 ◽  
Vol 62 (2) ◽  
pp. 49-51 ◽  
Author(s):  
Leman Tarhan ◽  
Hulya Ayar Kayali ◽  
Raziye Ozturk Urek


PeerJ ◽  
2015 ◽  
Vol 3 ◽  
pp. e1342 ◽  
Author(s):  
Benjamin W. Phillips ◽  
Mary M. Gardiner

Pumpkin (Cucurbita pepo) production relies on insect-mediated pollination, which is provided by managed and wild pollinators. The goals of this study were to measure the visitation frequency, longevity and temporal activity patterns of pumpkin pollinators and to determine if local habitat management and landscape composition affected this pollination service. We used video surveillance to monitor bee acitivty within male and female pumpkin flowers in 2011 and 2012 across a pollination window of 0600–1200 h. We also quantified the amount of pollen deposited in female flowers across this time period. In 2011,A. melliferamade significantly more floral visits than other bees, and in 2012Bombus spp. was the dominant pumpkin pollinator. We found variation in visitation among male and female pumpkin flowers, withA. melliferavisiting female flowers more often and spending longer per visit within them than male flowers in both 2011 and 2012. The squash beeP. pruinosavisited male flowers more frequently in 2012, but individuals spent equal time in both flower sexes. We did not find variation in the timing of flower visitation among species across the observed pollination window. In both 2011 and 2012 we found that the majority of pollen deposition occurred within the first two hours (0600–0800 h) of observation; there was no difference between the pollen deposited during this two-hour period and full pollination window (0600–1200 h). Local additions of sweet alyssum floral strips or a field buffer strip of native wildflowers did not have an effect on the foraging activity of bees or pollen deposition. However, semi-natural and urban habitats in the surrounding landscape were positively correlated with the frequency of flower visitation by wild pollinators and the amount of pollen deposited within female flowers.



2012 ◽  
Vol 61 (1) ◽  
pp. 99-106 ◽  
Author(s):  
Marta Dmitruk

The study was conducted on experimental plots in the conditions of Lublin. In the years 1998-2000 flowering, nectar secretion and insect visitation of male and female flowers of two winter squash (<i>Cucurbita maxima</i> Duch.) cultivars: 'Ambar' and 'Amazonka', were studied. The plants flowered from July to October. The flower life span was within the range of 7-10 hours. Female flowers of cv. Ambar were marked by the most abundant nectar secretion (129 mg). The nectar sugar content can be estimated as average (25%-35%). Winter squash nectar contained 84% of sucrose as well as 8-9% of fructose and 7%-8% of glucose. Flowers of the studied taxa were frequently foraged by the honey bee (66%-98% of total insects) and bumblebees (1%-30%).



2014 ◽  
Vol 2 (2) ◽  
pp. 67-71 ◽  
Author(s):  
Abdoul Amir Rahnama ◽  
Esmaeil Rahkhodaei

Date palm is unisexual, being either male or female. Male and female flowers grow on buds called Spathe, which opens naturally when fully mature. It is easy to identify the male and female flowers. Under the method of manual pollination, pollen from a male flower is smeared over female flowers. The pollen variety and pollination time have important effects on date palm fruit set, yield and quality. This experiment was carried out to study the effect of date pollinizer variety and pollination time on fruit set, growth and development of Medjhol date palm variety, in date palm garden of date palm and tropical fruit research institute of Iran during three years from 2009 to 2011. The trail was randomized complete block design in factorial manner with three pollen variety as Ghaname, Vardy, and Samesmave, two pollination time as 1-3 days before or after spathe opening and four replication. The results showed that the Vardy pollen had significant effects and increased the fertility percent and fruit yield, rather than two other pollen varieties. The pollen variety had no significant effects on fruit quality as total sugar, acidity, and bricx. The pollination time before spathe opening significantly increased fertility percent, decreased fruit weight and date palm yield. Finally the pollen variety and pollination time interaction effects showed that, application of Vardy pollen from 1-3 days after spathe opening with the most production date palm yield, equal 19.9 kilogram per any date palm trees, so this treatment is the best and are recommended.



2016 ◽  
Vol 24 (1) ◽  
pp. 47-55
Author(s):  
Agus Eko Prasetyo ◽  
Agus Susanto

Elaeidobius kamerunicus is the main pollinating agent in oil palm plantations in Indonesia today. The development of oil palm plantations in new areas requires introduction of these insects, moreover the new areas are located on different islands. First introduction of Elaeidobius kamerunicus Faust had been done from North Sumatra to Seram Island on 23 September 2013. The introduction was performed on larva and pupa stadium in 4-5 days post anthesising of male inflorescences. The introduction of E. kamerunicus using plywood boxes has an average risk of death by 7.89% at 6 days delivery period. Observation before releasing of the weevils showed that this insect was not detected in both of oil palm male and female flowers and the oil palm fruit set was very low approximately 11.27%. For about 500 weevils/ha were released in Marnuhu estate and could be developed into 362,401 weevils/ha in 5 months with 97.86% of oil palm sex ratio. The oil palm fruit sets were increased after 1 and 2 months introduction, 53.70% and 75.56 %, respectively. The lower sex ratio of oil palm or the more availability of male inflorescences make growth of E. kamerunicus population became faster and the greater number of weevils that visiting anthesising of female flowers make the higher value of oil palm fruit set.



2018 ◽  
Vol 24 (1) ◽  
pp. 47-55
Author(s):  
Agus Eko Prasetyo ◽  
Agus Susanto

Elaeidobius kamerunicus is the main pollinating agent in oil palm plantations in Indonesia today. The development of oil palm plantations in new areas requires introduction of these insects, moreover the new areas are located on different islands. First introduction of Elaeidobius kamerunicus Faust had been done from North Sumatra to Seram Island on 23 September 2013. The introduction was performed on larva and pupa stadium in 4-5 days post anthesising of male inflorescences. The introduction of E. kamerunicus using plywood boxes has an average risk of death by 7.89% at 6 days delivery period. Observation before releasing of the weevils showed that this insect was not detected in both of oil palm male and female flowers and the oil palm fruit set was very low approximately 11.27%. For about 500 weevils/ha were released in Marnuhu estate and could be developed into 362,401 weevils/ha in 5 months with 97.86% of oil palm sex ratio. The oil palm fruit sets were increased after 1 and 2 months introduction, 53.70% and 75.56 %, respectively. The lower sex ratio of oil palm or the more availability of male inflorescences make growth of E. kamerunicus population became faster and the greater number of weevils that visiting anthesising of female flowers make the higher value of oil palm fruit set.



Plants ◽  
2021 ◽  
Vol 10 (8) ◽  
pp. 1538
Author(s):  
Ana Teresa Alhinho ◽  
Miguel Jesus Nunes Ramos ◽  
Sofia Alves ◽  
Margarida Rocheta ◽  
Leonor Morais-Cecílio ◽  
...  

The sweet chestnut tree (Castanea sativa Mill.) is one of the most significant Mediterranean tree species, being an important natural resource for the wood and fruit industries. It is a monoecious species, presenting unisexual male catkins and bisexual catkins, with the latter having distinct male and female flowers. Despite the importance of the sweet chestnut tree, little is known regarding the molecular mechanisms involved in the determination of sexual organ identity. Thus, the study of how the different flowers of C. sativa develop is fundamental to understand the reproductive success of this species and the impact of flower phenology on its productivity. In this study, a C. sativa de novo transcriptome was assembled and the homologous genes to those of the ABCDE model for floral organ identity were identified. Expression analysis showed that the C. sativa B- and C-class genes are differentially expressed in the male flowers and female flowers. Yeast two-hybrid analysis also suggested that changes in the canonical ABCDE protein–protein interactions may underlie the mechanisms necessary to the development of separate male and female flowers, as reported for the monoecious Fagaceae Quercus suber. The results here depicted constitute a step towards the understanding of the molecular mechanisms involved in unisexual flower development in C. sativa, also suggesting that the ABCDE model for flower organ identity may be molecularly conserved in the predominantly monoecious Fagaceae family.



2002 ◽  
Vol 80 (11) ◽  
pp. 1203-1208 ◽  
Author(s):  
Lorena Ashworth ◽  
Leonardo Galetto

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.



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