Principles of Plant Genetics and Breeding. George Acquaah

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for crossing, and subsequently to produce seed.

      5.4.3 The flower structure

      Genetic manipulation of flowering plants by conventional tools is accomplished through the technique of crossing, which involves flowers. To be successful, the plant breeder should be familiar with the flower structure, regarding the parts and their arrangement. Flower structure affects the way flowers are emasculated (prepared for crossing by removing the male parts to make the flower female). The size of the flower affects the kinds of tools and techniques that can be used for crossing.

      5.4.4 General reproductive morphology

Schematic illustration of the typical flower has four basic parts: petals, sepals, pistil, and stamen. The shape, size, color, and other aspects of these floral parts differ widely among species.

      5.4.5 Types of flowers

      5.4.6 Gametogenesis

Schematic illustration of the gametogenesis in plants results in the production of pollen and egg cells. Pollen is transported by agents to the stigma of the female flower, from which it travels to the egg cell to unite with it.

      5.4.7 Pollination and fertilization

Pollination vector Flower characteristics
Wind Tiny flowers (e.g. grasses); dioecious species
Insects
Bees Bright and showy (blue, yellow); sweet scent; unique patterns; corolla provides landing pad for bees
Moths White or pale color for visibility at night; strong penetrating odor emitted after sunset
Beetles White or dull color; large flowers; solitary or inflorescence
Flies Dull or brownish color
Butterflies Bright colors (often orange, red); nectar located at base of long slender corolla tube
Bats Large flower with strong fruity

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