scholarly journals Pollination and Breeding System of Lowbush Blueberries, Vaccinium angustifolium Ait. and V. myrtilloides Michx. (Ericacaeae), in the Boreal Forest

2005 ◽  
Vol 119 (1) ◽  
pp. 48 ◽  
Author(s):  
Masayuki Usui ◽  
Peter G. Kevan ◽  
Martyn Obbard
Keyword(s):  
Boreal Forest ◽  
Fruit Set ◽  
Frost Damage ◽  
Fruit Production ◽  
Breeding Systems ◽  
Vaccinium Angustifolium ◽  
Cross Pollination ◽  
Different Ages ◽  
Canadian Boreal Forest ◽  
Pollination Systems

Breeding systems and pollination requirements of two wild lowbush blueberries, Vaccinium angustifolium and V. myrtilloides, in the Canadian boreal forest in the Chapleau Crown Game Preserve, Ontario, were tested. Fruit production, size and seediness were significantly higher in samples exposed to natural pollination than in those cross- or self-pollinated by hand. There were no significant differences among artificial treatments (variously hand-pollinated and bagged) except when cross-pollination (xenogamy) was done by insect pins. In V. angustifolium, the density of flowering varied with forest age (canopy closure). It was most in open areas and least in the sites with the most mature forest. Although fruit-set and seediness varied among forest habitats of different ages, there were no significant differences between sites in forests of different ages. Thus, pollination seems to be similarly effective no matter the age of the forest. In both species, fruit-set in 1992, which had severe June frosts, was markedly poorer than that in 1993 when the flowers suffered little frost damage. The combined number of complete and incomplete seeds from the fruit among the breeding and pollination systems tested were similar; however, the ratio of complete seeds to total seeds was greater from cross-pollinated than from self-pollinated flowers. Our observations indicate that there is little natural fruit-set without insect-mediated cross-pollination and that cross-pollination provides much better fruit and seed-set than does self-pollination.

Spring frost damage to placental tissues in lowbush blueberry flower buds

2001 ◽  
Vol 81 (4) ◽  
pp. 779-781 ◽  
Author(s):  
A. Randall ◽  
Olson and Leonard J. Eaton
Keyword(s):  
Key Words ◽  
Fruit Set ◽  
Frost Damage ◽  
Full Bloom ◽  
Flower Buds ◽  
Vaccinium Angustifolium ◽  
Spring Frost ◽  
Lowbush Blueberry ◽  
Commercial Yield ◽  
Spring Frosts

Closed flower buds and flowers at full bloom of Vaccinium angustifolium Ait. were collected from the field and histologically examined after severe spring frosts. Prior to anthesis, blackened ovarian placentae in closed buds were the only damaged tissues evident; placental damage may interfere with both seed and fruit set. Undetected frost damaged placentae may contribute to losses in commercial yield. Key words: Vaccinium, frost damage, placenta

The reproductive biology of boreal forest herbs. II. Phenology of flowering and fruiting

1987 ◽  
Vol 65 (10) ◽  
pp. 2047-2056 ◽  
Author(s):  
Kaius Helenurm ◽  
Spencer C. H. Barrett
Keyword(s):  
Boreal Forest ◽  
Fruit Set ◽  
Pollen Limitation ◽  
Fruit Production ◽  
Fruit Removal ◽  
Cornus Canadensis ◽  
Forest Herbs ◽  
Pollinator Service ◽  
Maianthemum Canadense ◽  
Major Factors

The flowering and fruiting phenologies of 12 boreal forest herbs were recorded during 1979 (flowering and fruiting) and 1980 (flowering only) in spruce–fir forests of central New Brunswick. The species studied were Aralia nudicaulis, Chimaphila umbellata, Clintonia borealis, Cornus canadensis, Cypripedium acaule, Linnaea borealis, Maianthemum canadense, Medeola virginiana, Oxalis montana, Pyrola secunda, Trientalis borealis, and Trillium undulatum. Flowering in the community occurred from mid-May to the end of July. The order of flowering was maintained in the 2 years, but the degree of synchronization of inflorescences differed in several species. Fruiting in the community began in mid-July and extended beyond the end of September. The percentage of buds that ultimately bore fruit ranged from 0 (Cypripedium acaule) to 61% (Aralia nudicaulis). With the exception of Cypripedium acaule, which received little pollinator service, the self-incompatible species, Cornus canadensis, Maianthemum canadense, and Medeola virginiana, experienced the lowest levels of fruit-set. Pollen limitation and predation of developing fruit appear to be the major factors limiting percentage fruit-set in boreal forest herbs. Fruit production varied with time of flowering of inflorescences in several species, with periods of low fruit-set tending to coincide with lower densities of flowering inflorescences. Significant rates of fruit removal by herbivores occurred in all sarocochorous species. Disappearance of fruits from infructescences ranged from 31 (Medeola virginiana) to 95% (Aralia nudicaulis), with highest removal rates occurring during periods of greatest fruit availability.

scholarly journals Blueberry Floral Attributes and Their Effect on the Pollination Efficiency of an Oligolectic Bee, Osmia ribifloris Cockerell (Megachilidae: Apoidea)

HortScience ◽  
2013 ◽  
Vol 48 (2) ◽  
pp. 136-142 ◽  
Author(s):  
Blair J. Sampson ◽  
Stephen J. Stringer ◽  
Donna A. Marshall
Keyword(s):  
Fruit Set ◽  
Fruit Production ◽  
Flower Size ◽  
Floral Traits ◽  
Solitary Bee ◽  
Pollination Efficiency ◽  
Seed Number ◽  
Cross Pollination ◽  
Berry Size ◽  
Fruit Abortion

We evaluated relationships between floral traits of 23 genotypes of southern blueberries and indices of pollination efficiency (fruit set, fruit abortion, seed number, and berry size) for Osmia ribifloris Cockerell, a manageable solitary bee. Flower size in Vaccinium and presumably ovary size were proportional to berry size, except for the tiny blooms of one V. tenellum clone (NC7808), which produce large commercial-sized berries of ≈2 g. Longer-styled blueberry flowers visited by O. ribifloris produced the heaviest berries with the most seeds. Osmia ribifloris reliably pollinated ‘Climax’ and ‘Tifblue’ rabbiteye blueberries. However, the peculiarly misshapen blooms of ‘Premier’ rabbiteye blueberry receive less pollination from O. ribifloris and yield berries containing 25% fewer seeds. Fruit set for these misshapen ‘Premier’ flowers was equivalent to that of intact flowers indicating that this floral polymorphism would not greatly alter cultivar performance. For seven Vaccinium species, wild and cultivated alike, 80% to 100% of a plant’s fruit production depends on efficient cross-pollination by bees such as O. ribifloris.

scholarly journals Pollination biology and reproduction of Seemannia sylvatica (Kunth) Hanstein (Gesneriaceae) in the Serra da Bodoquena National Park, Mato Grosso do Sul

2011 ◽  
Vol 11 (4) ◽  
pp. 125-130 ◽  
Author(s):  
Eduardo Camargo ◽  
Licléia da Cruz Rodrigues ◽  
Andréa Cardoso Araujo
Keyword(s):  
Breeding System ◽  
Fruit Set ◽  
Riparian Forest ◽  
Floral Biology ◽  
Nectar Production ◽  
Mato Grosso ◽  
Nectar Volume ◽  
Cross Pollination ◽  
Self Pollination ◽  
Different Ages

In Brazil, the family Gesneriaceae is represented by 23 genera and approximately 200 species. Seemannia sylvatica is an herb that occurs in dense populations in the riverbeds at Serra da Bodoquena. Goals of this study were to report the floral biology (on the first five days of anthesis), as well as to determine the breeding system and the pollinators of S. sylvatica. Data collection was conducted from June 2005 to July 2006 through monthly field trips, lasting for five days. Data on floral biology, breeding system and on the floral visitors were taken from individuals located along a track 2500 m long, in riparian forest of Salobrinha river. Flowers of S. sylvatica are tubular, red, with no perceptive odor and lasted more than five days (ca. 10 - 20 days in individuals transferred to an urban garden and kept in vases). Seemania sylvatica is protandrous, and the male phase occurred between the first and the fourth days of anthesis, while the female one started in the fifth day. Mean nectar volume secreted was 4.77 ± 3.2 µl, with a significative variation among flowers of different ages. Otherwise, nectar concentration average was 9.71 ± 4.41%, and did not varied significantly in flowers of different ages. The flowers of S. sylvatica were pollinated mainly by the hummingbirds Phaethornis pretrei and Thalurania furcata, and pierced by the bee Ceratina chloris. The butterfly Parides anchises orbygnianus was considered an occasional pollinator of these flowers. Seemannia sylvatica is self-compatible, since fruit set occurred on the experiments of spontaneous self-pollination, manual self-pollination, cross-pollination and open pollination (control). The protandry, coupled with the pattern of nectar production, characterized by low volume and solute concentration, which induces the pollinators to visit different flowers in a given circuit foraging, act maximizing the likelihood of cross-pollination in S. sylvatica. Moreover, the high proportion of fruit set by autogamy is an important strategy considering that S. sylvatica is visited by few species, being pollinated mainly by P. pretrei. Therefore, in the absence of these visitors, the formation of fruits may be achieved.

The reproductive biology of boreal forest herbs. I. Breeding systems and pollination

1987 ◽  
Vol 65 (10) ◽  
pp. 2036-2046 ◽  
Author(s):  
Spencer C. H. Barrett ◽  
Kaius Helenurm
Keyword(s):  
Boreal Forest ◽  
Reproductive Biology ◽  
Fruit Set ◽  
Experimental Studies ◽  
Reproductive Mode ◽  
Breeding Systems ◽  
Cornus Canadensis ◽  
Forest Herbs ◽  
Maianthemum Canadense ◽  
Floral Syndromes

Detailed observations and experimental studies of the reproductive biology of 12 boreal forest herbs were conducted over a 3-year period (1978–1980) in spruce–fir forests of central New Brunswick. The species examined were Aralia nudicaulis, Chimaphila umbellata, Clintonia borealis, Cornus canadensis, Cypripedium acaule, Linnaea borealis, Maianthemum canadense, Medeola virginiana, Oxalis montana, Pyrola secunda, Trientalis borealis, and Trillium undulatum. All taxa are insectpollinated perennials and most exhibit clonal growth. Floral syndromes of the understory community are relatively unspecialized with many species possessing small white or green flowers. A total of 103 taxa of insects were collected from flowers during the 1979 season. Bombus spp. are the major pollinators of 5 of the 12 species. Syrphid flies, bee flies, and halictid and andrenid bees were also commonly observed. Controlled pollinations were undertaken to determine the breeding systems of herbs. Bagged, self-, cross- and open-pollinated treatments were used to investigate the capacity for self-pollination, compatibility status, and factors influencing fecundity in each species. A diversity of reproductive systems was revealed. Six species are completely dependent on insects for pollination, four species are weakly autogamous, one is strongly autogamous, and one appears to be apomictic. Comparisons of fruit-set and seed set from controlled self- and cross-pollinations indicate that four species are strongly self-compatible, one is dioecious, and the remainder display varying degrees of self-incompatibility. Despite this variation, outbreeding appears to be the most common reproductive mode. In several species there is evidence that low pollinator service limits fruit-set.

Reproductive Responses of Capsicum annuum to High Temperatures

HortScience ◽  
1998 ◽  
Vol 33 (3) ◽  
pp. 543c-543
Author(s):  
Ami N. Erickson ◽  
Albert H. Markhart
Keyword(s):  
Capsicum Annuum ◽  
High Temperatures ◽  
Fruit Development ◽  
Flower Development ◽  
Fruit Set ◽  
Fruit Production ◽  
Yield Reduction ◽  
Bud Size ◽  
Growth Chambers ◽  
Constant Growth

Fruit yield reduction due to high temperatures has been widely observed in Solanaceous crops. Our past experiments have demonstrated that Capsicum annuum cultivars Ace and Bell Boy completely fail to produce fruit when grown at constant 33 °C. However, flowers are produced, continually. To determine which stages of flower development are sensitive to high temperatures, pepper buds, ranging in size from 1 mm to anthesis, were exposed to high temperatures for 6 hr, 48 hr, 5 days, or for the duration of the experiment. Fruit set for each bud size was determined. Exposure to high temperatures at anthesis and at the 2-mm size stage for 2 or more days significantly reduced fruit production. To determine whether inhibition of pollination, inhibition of fertilization, and/or injury to the female or male structures prevents fruit production at high temperatures, flowers from pepper cultivars Ace and Bell Boy were grown until flowers on the 8th or 9th node were 11 mm in length. Plants were divided between 25 °C and 33 °C constant growth chambers for 2 to 4 days until anthesis. At anthesis, flowers from both treatments were cross-pollinated in all combination, and crosses were equally divided between 33 or 25 °C growth chambers until fruit set or flowers abscised. All flower crosses resulted in 80% to 100% fruit set when post-pollination temperatures were 25 °C. However, post-pollination temperatures of 33 °C significantly reduced fruit production. Reduced fruit set by flowers exposed to high temperatures during anthesis and pollination is not a result of inviable pollen or ovule, but an inhibition of fertilization or initial fruit development.

Two new species of Oidiodendron from boreal forest soils

1968 ◽  
Vol 46 (3) ◽  
pp. 203-206 ◽  
Author(s):  
R. A. A. Morrall
Keyword(s):  
New Species ◽  
Boreal Forest ◽  
Forest Soils ◽  
Nomen Dubium ◽  
Two New Species ◽  
Canadian Boreal Forest

Oidiodendron periconioides Morrall sp. nov. and O. chlamydosporicum Morrall sp. nov. are described from Canadian boreal forest soils. O. gracile Zhdanova is considered to be a nomen dubium.

Sign in / Sign up

Export Citation Format

Share Document