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Showing 1 to 9 of 9 for “"Pollen viability"”.

  1. Why do flowers in Namaqualand close? : Flower closure in relation to the environment and pollen sensitivity to moisture

    … represent an adaptation for protecting sensitive pollen from damage by moisture (dew, rain). The literature dealing with the subject is sparse and we addressed this gap by investigating patterns of flower closure in relation with environmental variables (potential cues). We also determined the …

    cape-town Repository record for Why do flowers in Namaqualand close? : Flower closure in relation to the environment and pollen sensitivity to moisture (opens in a new tab)

  2. Isolation in Tragopogon (Compositae)

    … versus when they were left uncovered. (2) Pollen viability counts were made to determine the incidence of viable microspores produced by plants of the three taxa. (3) Cytologic studies of microsporogenesis in the two parental species and their interspecific hybrid were made to compare …

    ballstate-thes Repository record for Isolation in Tragopogon (Compositae) (opens in a new tab)

  3. The physiological effects of heat stress on anthesis and pollination in domesticated sunflowers (Helianthus annuus L.)

    … the effect of heat stress on timing of pollen emergence, style elongation rate, pollinator visits, pollen viability and stigma receptivity. We sampled during the anthesis period in a field setting under different summer conditions, including sunny and overcast days each with artificially …

    pretoria Repository record for The physiological effects of heat stress on anthesis and pollination in domesticated sunflowers (Helianthus annuus L.) (opens in a new tab)

  4. Genetics Analysis of Standing Variation for Floral Morphology and Fitness Components in a Natural Population of Mimulus Guttatus (Common Monkeyflower)

    … documented in this population for fertility and viability (Willis 1999 a,b), while previous biometric experiments have demonstrated that some of the floral variation in this site is due to common alleles perhaps maintained by balancing selection (Kelly and Willis 2001, Kelly 2003). Detailed …

    duke Repository record for Genetics Analysis of Standing Variation for Floral Morphology and Fitness Components in a Natural Population of Mimulus Guttatus (Common Monkeyflower) (opens in a new tab)

  5. Macromolecular organization of flavonoid biosynthesis in Arabidopsis thaliana

    … it was shown that flavonols are not required for pollen viability in A. thaliana as they are in maize and petunia. I also describe a novel method to clone fragments of DNA without ligase using the polymerase chain reaction (PCR). To establish an experimental model I have used a variety of …

    vt Repository record for Macromolecular organization of flavonoid biosynthesis in Arabidopsis thaliana (opens in a new tab)

  6. Self-incompatibility in Cosmos atrosanauineus: a rare Mexican endemic species of Asteraceae

    … that produces viable gametes with ~30% pollen viability. Self- and cross-pollinations of C. atrosanguineus are strongly incompatible with an average of zero pollen grains germinating per stigma. In contrast, cross and self-pollinations in C. bipinnatus and C. sulphureus produced three …

    greenwich Repository record for Self-incompatibility in Cosmos atrosanauineus: a rare Mexican endemic species of Asteraceae (opens in a new tab)

  7. POPULATION GENOMICS, DISTRIBUTION AND REPRODUCTIVE ECOLOGY OF AN ITALIAN STENO-ENDEMIC CHASMOPHYTE, CAMPANULA RAINERI

    … ecology of C. raineri, from pollinator guilds to pollen and seed quality (Chapter 4). Future SDMs suggest a decrease in habitat suitability at lower-elevation sites, where C. raineri populations exhibited reduced fitness (correlation coefficients = 0.62 and 0.93 for seed germination and pollen

    milano Repository record for POPULATION GENOMICS, DISTRIBUTION AND REPRODUCTIVE ECOLOGY OF AN ITALIAN STENO-ENDEMIC CHASMOPHYTE, CAMPANULA RAINERI (opens in a new tab)

  8. Effects of systemic fungicides on floral attributes, pollination and fruit aroma in strawberries

    … these interactions, I analysed floral volatiles, pollen weight and pollen protein from greenhouse-grown plants and observed the foraging behaviour of bumblebees towards these flowers, under controlled conditions. Additionally, I analysed the pollen viability and nectar fungi composition from …

    bielefeld Repository record for Effects of systemic fungicides on floral attributes, pollination and fruit aroma in strawberries (opens in a new tab)