Short Note on Polination


I.             Pollination - definition and breeding pattern
                A.            Pollination - transfer of pollen from the anther to the stigma
                B.            Breeding pattern
                                1.             Plants are at the mercy of pollen carriers (vectors)
                                                a)            Plants pollinated by vectors which travel great distances
                                                                1)            Wind & bumblebees - lead to "effective" breeding populations
                                                b)            Plants pollinated by vectors which travel short distances
                                                                1)            Small insects - localized breeding populations
II.            Pollination systems:  self- and cross-pollination
                A.            Self-pollination - plants pollinated by their own pollen
                                1.             Many cultivated plants (beans, peas, and tomatoes)
                                                a)            Good/bad news of self-pollination
                                                                1)            Homozygosity (more uniform)
                                                                2)            Focus on adaptation to environment (desert animals)
                B.            Cross-pollination - plants receiving pollen from other plants
                                1.             Pollination by insects, wind, birds, mammals, and water
                                2.             Mechanisms to prevent self-pollination (most plants)
                                                a)            Self-incompatibility mechanisms - Camellia
                                                b)            Timing mechanisms (readiness of stigma & anther) - lily and amaryllis
                                                c)             Sex parts on different plants (dioecious) - ginkgo, willow, and poplar
                                3.             Good/bad news of cross-pollination
                                                a)            Heterozygosity
                                                b)            Focus on diversity and survival in environment
III.          Regulatory factors of pollination vectors - maximization of pollination efficiency
                A.            Wind pollination - no color, little scent, small, and often dioecious
                B.            "Rewards" provided by the plant
                                1.             Food (insects, birds, and mammals)
                                                a)            Pollen, nectar, and oil
                                2.             Sensory (insects, birds, and mammals)
                                                a)            Odor, visual (shape, size, color), temperature, motion
                C.            Attracting pollinators
                                1.             Most pollinators
                                                a)            Attracted to a single showy flower
                                                b)            Bees cannot perceive red light - but can perceive UV light
                                                                1)            Bees mostly attracted to yellow and blue flowers (w / UV stuff)
                                2.             Animal pollinators (insects and mammals)
                                                a)            FOOD!!! - nectar, oil, pollen, etc.
                                                b)            Rest area - warmth, breeding, etc.
                                                c)             Odor - sweet, fruity, sexy, etc.
                                3.             Insect pollinators
                                                a)            Color & nectar guides
                                                b)            Odor - sweet, fruity, putrid (flies & beetles), "female-like"
                                4.             Specific insects:  moths and butterflies
                                                a)            Day and night flowers
                                                b)            Moths - flowers emit fragrance at night
                                                c)             Some butterflies see red light
                                5.             Birds
                                                a)            Can see red light
                                                b)            Flowers usually not scented, but brightly colored (cacti, columbines, hibiscus, bananas, etc.)
                                6.             Mammals - bats, marsupials, and monkeys
                                                a)            Bats - strong, fruity odors

                                                b)            Others (climbers) - possum, monkey

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