Search results for "Pollination"

THE ROLES OF PLANT VOLATILES AND THEIR POTENTIAL USE AS FLY ATTRACTANTS

2014

The essential oils composition of the skin, pulp and seeds from fruits of two Sicilian cultivars of Opuntia ficus-indica (cv. Sanguigna and cv. Surfarina has been obtainedby hydrodistillation and the possible semiochemical roles have been investigated comparing the data with those reported in the literature. Several compounds identified in this study have been reported to influence the behaviour of Ceratitis capitata, a phytophagous which causes severe damages to severalcrops including O. ficus-indica and the kairomonal activity of the odour of the fruits seems provided by a blend of compounds found in the various matrices analysed. In sapromyiophilous plants, up to date, long range attract…

Ontogeny of the Calliandra – massulae (Mimosaceae: Ingeae), and the associated viscin body

2006

Abstract Polyads, called also massulae, are common in the Mimosaceae. Within this family, only in Calliandra (s. l.) polyads show a remarkable morphological variation: 16-grained lens-shaped massulae in the neotropical Zapoteca (syn. Calliandra p.p.), and highly asymmetric eight-grained massulae in Calliandra (s. str.). As a further specialisation the massulae in Calliandra (s. str.) possess a sticky appendage called a viscin body. The form and ontogeny of this unique two-dimensional construction of the massula is of particular interest. In Calliandra (s. str.) the octad is normally the developmental product of the initiation stage, beginning with one pollen mother cell (PMC). In total, Cal…

Floral volatiles in a sapromyiophilous plant and their importance in attracting house fly pollinators

2015

Floral scent in sapromyiophilous plants often consists of complex blends with not only fetid (e.g., sulfides) but also sweet (e.g., terpenoids) volatile organic compounds and a recent study suggests that both groups of compounds are involved in pollinator attraction. However, little is known about the number and identity of compounds involved in pollinator attraction in these deceptive plants that mimic breeding sites of fly pollinators. In the present paper, we studied flower volatiles of sapromyiophilous Periploca laevigata and their capability to elicit biological responses in one of the pollinator species, Musca domestica. Floral volatiles were collected by dynamic headspace and analyse…

Olfactory attraction of the hornet Vespa velutina to honeybee colony odors and pheromones.

2014

19 pages; International audience; Since the beginning of the last century, the number of biological invasions has continuously increased worldwide. Due to their environmental and economical consequences, invasive species are now a major concern. Social wasps are particularly efficient invaders because of their distinctive biology and behavior. Among them, the yellow-legged hornet, Vespa velutina, is a keen hunter of domestic honeybees. Its recent introduction to Europe may induce important beekeeping, pollination, and biodiversity problems. Hornets use olfactory cues for the long-range detection of food sources, in this case the location of honeybee colonies, but the exact nature of these c…

2014

Since the beginning of the last century, the number of biological invasions has continuously increased worldwide. Due to their environmental and economical consequences, invasive species are now a major concern. Social wasps are particularly efficient invaders because of their distinctive biology and behavior. Among them, the yellow-legged hornet, Vespa velutina, is a keen hunter of domestic honeybees. Its recent introduction to Europe may induce important beekeeping, pollination, and biodiversity problems. Hornets use olfactory cues for the long-range detection of food sources, in this case the location of honeybee colonies, but the exact nature of these cues remains unknown. Here, we stud…

Effects of temperature and pollination site on pollen performance in Betula pendula Roth – evidence for genotype-environment interactions

2000

We studied whether the differences between genetically different pollen donors (Betula pendula Roth clones) with respect to pollen-tube growth rate were consistent under different thermal conditions during pollen germination in vivo and in vitro. We conducted a single-donor hand-pollination experiment with same pollen donors and recipients in a plastic house seed orchard and at an outdoor clone collection. The prevailing daily mean temperature during pollen germination was 13°C higher in the plastic house than outdoors. The pollen-tube growth rate of each pollen donor was additionally determined in vitro on agar medium at five temperatures (10°, 15°, 22°, 30° and 35°C). A significant intera…

The role of native flower visitors in pollinating Opuntia ficus-indica (L.) Mill., naturalized in Sicily

2011

Abstract The role of insects in pollination and consequently in fruit set and quality was assessed in two commercial orchards of the cactus pear, Opuntia ficus-indica (L.) Mill., in Agrigento Province, Sicily. In 1997, insects visiting flowers were sampled during May–June (the first bloom) and July (the second bloom, induced by the “scozzolatura” practise). More than 50 insect species belonging to 10 orders were collected in May–June, while only five species of Hymenoptera Apoidea were collected in July. The quality of fruits arising from the second bloom showed that Hymenoptera alone were able to guarantee effective pollination. To verify the role of insects in pollination in 1996 (during …

Andromonoecy and developmental plasticity in Chaerophyllum bulbosum (Apiaceae–Apioideae)

2013

Background and Aims: Andromonoecy, the presence of hermaphrodite and male flowers in the same individual, is genetically fixed or induced, e.g. by fruit set. Little is known about the forces triggering andromonoecy in the Apiaceae. In the present study, a natural population of the protandrous Chaerophyllum bulbosum was investigated to elucidate architectural constraints and effects of resource reallocation. Methods: Three sets of plants (each n ¼ 15) were treated by hand pollination, pollinator exclusion and removal of low-order inflorescences. Fifteen untreated plants were left as controls. Key Results: Untreated plants produce umbels up to the third branch order, with increasing proportio…

Inflorescence-visiting insects of a functionally dioecious wild grapevine

2018

The wild grapevine [Vitis vinifera L. subsp. sylvestris (Gmelin) Hegi] is the Eurasian dioecious ancestral form of mostly monoecious domesticated cultivars (Vitis vinifera subsp. vinifera). There are different hypotheses about grapevine pollination, varying from insect to wind pollination to spontaneous self-pollination. The aim of this paper is to update our knowledge on the biology of the wild grapevine by studying the insects visiting their inflorescences. During the fieldworks, floral visitors were observed, captured and identified. The most frequent insects visiting both sexes of wild grapevine were beetles (55%) followed by bees (45%). The present study shows that although in vineyard…

Api e pronubi selvatici nella produzione di Coriandrum sativum L. (Famiglia Apiaceae) in Sicilia occidentale

2009

Coriandrum sativum L. (Apiaceae - Umbelliferae) is an aromatic annual plant, subspontaneous in several Mediterranean countries. It is cultivated in various states of western Asia, North Africa and Europe. In Italy with the increment of immigration the request of coriandrum fresh state (grass cimicina) and powder to seeds are in increase. In Sicilian territory, for estimating the role of pollinators (wild pollinators and bees) in the increment of seeds production of Coriandrum sativum, a triennial surveying has been carried out, comparing three treatments: self-pollination, bees pollination and free pollination. The production of Coriandrum sativum obtained have been in the first year of 132…