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Tamiji Inoue - One of the best experts on this subject based on the ideXlab platform.

  • thrips Cross Pollination of popowia pisocarpa annonaceae in a lowland dipterocarp forest in sarawak1
    Biotropica, 1998
    Co-Authors: Kuniyasu Momose, Teruyoshi Nagamitsu, Tamiji Inoue
    Abstract:

    This paper reports thrips (Thysanoptera) Cross-Pollination in the primitive angiosperm, Popowia pisocarpa (Annonaceae), in lowland rain forest of Sarawak, Malaysia. Flowers of 1? pisocarpa have a tiny Pollination chamber (3-4 mm in depth) with the entrance almost closed by the disk-shaped stigmatic heads, allowing only small insects to enter. Experiments showed that thrips were effective pollinators and flowers of P? pisocarpa were self-incompatible. Seed set was limited by pollen. Clumped adult trees had higher seed-set than more distant individuals (>5 m from nearest flowering neighbor), indicating limited inter-tree movement by thrips.

  • Thrips Cross‐Pollination of Popowia pisocarpa (Annonaceae) in a Lowland Dipterocarp Forest in Sarawak1
    Biotropica, 1998
    Co-Authors: Kuniyasu Momose, Teruyoshi Nagamitsu, Tamiji Inoue
    Abstract:

    This paper reports thrips (Thysanoptera) Cross-Pollination in the primitive angiosperm, Popowia pisocarpa (Annonaceae), in lowland rain forest of Sarawak, Malaysia. Flowers of 1? pisocarpa have a tiny Pollination chamber (3-4 mm in depth) with the entrance almost closed by the disk-shaped stigmatic heads, allowing only small insects to enter. Experiments showed that thrips were effective pollinators and flowers of P? pisocarpa were self-incompatible. Seed set was limited by pollen. Clumped adult trees had higher seed-set than more distant individuals (>5 m from nearest flowering neighbor), indicating limited inter-tree movement by thrips.

Spencer C H Barrett - One of the best experts on this subject based on the ideXlab platform.

  • botany specialized bird perch aids Cross Pollination
    Nature, 2005
    Co-Authors: Bruce Anderson, William W. Cole, Spencer C H Barrett
    Abstract:

    A plant scores by providing an access point for visiting sunbirds to feed on its nectar. Birds may hover over or perch on flowers when feeding on nectar1, and this assists Cross-Pollination if they then visit other plants. Here we investigate the curious sterile inflorescence axis of the South African Cape endemic ‘rat's tail’ plant (Babiana ringens, Iridaceae), whose function — unlike in other bird-pollinated plants — is exclusively to provide a perch for foraging birds. We find that this structure promotes the plant's mating success by causing the malachite sunbird (Nectarinia famosa), its main pollinator, to adopt a position ideal for the Cross-Pollination of its unusual ground-level flowers.

  • Botany: Specialized bird perch aids Cross-Pollination
    Nature, 2005
    Co-Authors: Bruce Anderson, William W. Cole, Spencer C H Barrett
    Abstract:

    Birds may hover over or perch on flowers when feeding on nectar, and this assists Cross-Pollination if they then visit other plants. Here we investigate the curious sterile inflorescence axis of the South African Cape endemic 'rat's tail' plant (Babiana ringens, Iridaceae), whose function--unlike in other bird-pollinated plants--is exclusively to provide a perch for foraging birds. We find that this structure promotes the plant's mating success by causing the malachite sunbird (Nectarinia famosa), its main pollinator, to adopt a position ideal for the Cross-Pollination of its unusual ground-level flowers.

Kuniyasu Momose - One of the best experts on this subject based on the ideXlab platform.

  • thrips Cross Pollination of popowia pisocarpa annonaceae in a lowland dipterocarp forest in sarawak1
    Biotropica, 1998
    Co-Authors: Kuniyasu Momose, Teruyoshi Nagamitsu, Tamiji Inoue
    Abstract:

    This paper reports thrips (Thysanoptera) Cross-Pollination in the primitive angiosperm, Popowia pisocarpa (Annonaceae), in lowland rain forest of Sarawak, Malaysia. Flowers of 1? pisocarpa have a tiny Pollination chamber (3-4 mm in depth) with the entrance almost closed by the disk-shaped stigmatic heads, allowing only small insects to enter. Experiments showed that thrips were effective pollinators and flowers of P? pisocarpa were self-incompatible. Seed set was limited by pollen. Clumped adult trees had higher seed-set than more distant individuals (>5 m from nearest flowering neighbor), indicating limited inter-tree movement by thrips.

  • Thrips Cross‐Pollination of Popowia pisocarpa (Annonaceae) in a Lowland Dipterocarp Forest in Sarawak1
    Biotropica, 1998
    Co-Authors: Kuniyasu Momose, Teruyoshi Nagamitsu, Tamiji Inoue
    Abstract:

    This paper reports thrips (Thysanoptera) Cross-Pollination in the primitive angiosperm, Popowia pisocarpa (Annonaceae), in lowland rain forest of Sarawak, Malaysia. Flowers of 1? pisocarpa have a tiny Pollination chamber (3-4 mm in depth) with the entrance almost closed by the disk-shaped stigmatic heads, allowing only small insects to enter. Experiments showed that thrips were effective pollinators and flowers of P? pisocarpa were self-incompatible. Seed set was limited by pollen. Clumped adult trees had higher seed-set than more distant individuals (>5 m from nearest flowering neighbor), indicating limited inter-tree movement by thrips.

Bruce Anderson - One of the best experts on this subject based on the ideXlab platform.

  • botany specialized bird perch aids Cross Pollination
    Nature, 2005
    Co-Authors: Bruce Anderson, William W. Cole, Spencer C H Barrett
    Abstract:

    A plant scores by providing an access point for visiting sunbirds to feed on its nectar. Birds may hover over or perch on flowers when feeding on nectar1, and this assists Cross-Pollination if they then visit other plants. Here we investigate the curious sterile inflorescence axis of the South African Cape endemic ‘rat's tail’ plant (Babiana ringens, Iridaceae), whose function — unlike in other bird-pollinated plants — is exclusively to provide a perch for foraging birds. We find that this structure promotes the plant's mating success by causing the malachite sunbird (Nectarinia famosa), its main pollinator, to adopt a position ideal for the Cross-Pollination of its unusual ground-level flowers.

  • Botany: Specialized bird perch aids Cross-Pollination
    Nature, 2005
    Co-Authors: Bruce Anderson, William W. Cole, Spencer C H Barrett
    Abstract:

    Birds may hover over or perch on flowers when feeding on nectar, and this assists Cross-Pollination if they then visit other plants. Here we investigate the curious sterile inflorescence axis of the South African Cape endemic 'rat's tail' plant (Babiana ringens, Iridaceae), whose function--unlike in other bird-pollinated plants--is exclusively to provide a perch for foraging birds. We find that this structure promotes the plant's mating success by causing the malachite sunbird (Nectarinia famosa), its main pollinator, to adopt a position ideal for the Cross-Pollination of its unusual ground-level flowers.

Peter Stamp - One of the best experts on this subject based on the ideXlab platform.

  • Weather effects on Cross-Pollination in maize
    Crop Science, 2010
    Co-Authors: André Vogler, Ingrid Aulinger-leipner, Mario Bertossa, Peter Stamp
    Abstract:

    Control of pollen dispersal is critical for the successful coexistence of genetically modified (GM) maize (Zea mays L.) and conventional maize. The impact of climate on Cross-Pollination by GM pollen was simulated in two field experiments with a color-recessive white-grain receptor DSP17007 and a color-dominant yellow-grain pollen donor in 2005 and 2006. The day after silk exertion of about 2500 marked single plants was taken as the basis for comparing weather data (maximum and minimum temperatures, relative humidity, wind speed, and average wind direction) with data on the Cross-Pollination of the white-grain receptor. Scattered significant correlations were found for all weather factors; only the minimum temperature at night had consistent negative correlations with rates of Cross-Pollination ranging from r = -0.22 to -0.45, indicating that the latter decreased as temperatures at night increased. In previous complementary field and growth chamber experiments, the grain set on one inbred line correlated significantly negatively with temperature up to 24 h before Pollination (r = -0.55 to -0.66) because of pollen agglutination. This affects medium-distance pollen dispersals to a greater extent than short-distance ones; thus, Cross-Pollination with GM maize may be lower when the pollen donor has a proclivity for pollen agglutination at a high minimum temperature at night.

  • Impact of topography on Cross-Pollination in maize (Zea mays L.)
    European Journal of Agronomy, 2009
    Co-Authors: André Vogler, Henri Eisenbeiss, Ingrid Aulinger-leipner, Peter Stamp
    Abstract:

    Understanding Cross-Pollination is important to achieve the coexistence of genetically modified (GM) and conventional maize (Zea mays L.); it is still not known whether topography favors or hinders Cross-Pollination. In 2005 and 2006, the effect of gradients of 3.4-6.8° on Cross-Pollination was investigated in the canton of Zurich, Switzerland. Cross-Pollination was revealed by the presence of yellow-grains on a white-grain hybrid at distances up to 17.5 m from the yellow-grain pollen donor hybrid. The measurements of the inclination of the slope were based on aerial images data taken by an unmanned GPS/INS (Global Positioning System/Inertial Navigation System)-based and stabilized model helicopter, which delivered precise altitude-based data for sampling points at tassel height. The rate of Cross-Pollination increased significantly with decreasing altitude of the receptor field (r = 0.36-0.64). However, the effect seems to be weaker than that of other factors like wind direction and velocity. © 2009.

  • Short-distance Cross-Pollination of maize in a small-field landscape as monitored by grain color markers
    European Journal of Agronomy, 2008
    Co-Authors: Michael Bannert, André Vogler, Peter Stamp
    Abstract:

    Abstract Results of studies on Cross-Pollination in small field environments with regard to donor/receptor surface ratios and flower synchrony are scarce. In 2003 and 2004, six field experiments on Cross-Pollination were carried out in the cantons of Zug and Zurich, two hilly regions of Switzerland. Three (Monopol, Romario and PR39G12) color-dominant yellow-grain maize varieties (Zea mays L.) were planted in close proximity (0.8 m) to color-recessive white-grain maize (DSP17007). The factors of influence were size of the donor and receptor parts of the field and flower synchrony, tested in a tight grid pattern (2.4 m × 10 m; 6000 ears ha−1). Widely varying field size ratios of donors to receptors (about 4:1–1:8) did not influence the Cross-Pollination rate at distances of 0–20 m from the pollen donor. The synchrony between pollen shedding of the donor and silking of the receptor had a large impact on Cross-Pollination. In relation to the mid-phase of silk emergence in the receptor field, a temporal isolation of five and seven days resulted in a significant decrease in Cross-Pollination by more than 80% in comparison to full synchrony. However, in a receptor field with irregular emergence of a number of weak, late-flowering plants led to a remarkable increase in Cross-Pollination, despite an average temporal separation of 7 days. Marked Cross-Pollination was restricted to distances up to 15 m; thus, average rates of Cross-Pollination above 0.9% were easily managed in small fields.

  • Cross-Pollination of maize at long distance
    European Journal of Agronomy, 2007
    Co-Authors: Michael Bannert, Peter Stamp
    Abstract:

    Abstract In a 2-year-study in Switzerland the Cross-Pollination of maize was investigated by using the occurrence of yellow grains in 13 white grain maize fields as a marker of Cross-Pollination from neighbouring yellow grain fields. Distances of 50–4500 m between pollen-donor and pollen-receptor fields were investigated. In no case, the Cross-Pollination of the whole field was more than 0.02%. Four white grain maize fields, located in downwind distances of 50–371 m in the main wind direction, showed low but marked Cross-Pollination at the field border exposed to the nearest yellow grain maize field. In every field some Cross-Pollinations with a low rate, on an average of 1.8% of the sampled ears, could be found. These Cross-Pollinations were mainly single Cross-Pollinations on the ear. Horizontal wind speed measurements during flowering time in relation to the settling speed of maize pollen showed a potential horizontal pollen dispersal distance of up to 55 m. The few observed Cross-Pollinations over longer distances could be due to gusts or vertical movements of the wind (e.g., thermal or turbulence effects). In some fields spots of higher Cross-Pollinations were found. In the cases where the surrounding plants were checked a yellow grain maize seed contamination (0.004% of the seedstock) in the white seeds could be determined as the reason for these “hot-spots”.