Plant Engineering

• Protoplasts and tissue culture are used as models for studying plant development.
• Plant storage organs, such as tubers, are a part of plant development.
• The tuberization mechanism and hormonal regulation of tuberization are topics in plant development.
• Flowering, epinasty, leaf senescence, induction of roots and root hair are aspects of plant development.
• Senescence and programmed cell death are topics in plant development.
• Signal transduction is a part of plant development.
• Plant development shares common features with animal development, including fertilization of a 1N (haploid) egg cell by a 1N sperm nucleus, cell division and growth, and molecular mechanisms of determination that generate different cell types.
• Plant cells do not migrate as do bacteria or animal cells, and plant shape forms based on the rate of cell division and the direction of elongation.
• Plant development is continuous, with new plant organs formed throughout their life by clusters of embryonic cells called meristem.
• Plants have tremendous developmental plasticity, with lost plant parts regenerated by meristems and entire plants regenerated from single cells.
• Abiotic factors are the non-living parts of the environment that can often have a major influence on living organisms.
• Biotic factors are all of the living things in an ecosystem, such as plants and animals, and these living things interact with one another in many ways.
• Light intensity, temperature, moisture levels, soil pH and mineral content, wind intensity and direction, and availability of carbon dioxide are factors that can affect plant development.
• Abiotic factors can limit photosynthesis, affect the distribution of plants, and therefore the distribution of animals that eat plants.
• Biotic factors can affect plant development through pollination, interaction among plants growing in a community, interaction between plants and soil micro-organisms, and pathogens.
• The egg cell and polar nuclei are contained within the embryo sac.
• In embryogenesis, the suspensor develops from the basal cell and anchors the embryo to the endosperm, serving as a nutrient conduit for the developing embryo.
• The egg cell and polar nuclei are contained within the embryo sac.
• Another sperm nucleus fertilizes a polar cell with two 1N nuclei, generating a 3N triploid endosperm, which provides nutrients to the developing embryo.
• The formation of two cotyledons in dicots gives the embryo a heart-shaped appearance.
• Most of the plant embryo develops from the apical (terminal) cell.
• Plant embryogenesis begins with an asymmetric cell division, resulting in a smaller apical (terminal) cell and a larger basal cell.
• The globular shape of the embryo is then lost as the cotyledons (embryonic leaves) begin to form.
• The first asymmetric division provides polarity to the embryo.
• Plant tissue culture is a technique of growing plant cells, tissues, organs, seeds or other plant parts in a sterile environment on a nutrient medium.
• One sperm nucleus fertilizes the egg, generating a 2N diploid zygote.
• Upright cotyledons can give the embryo a torpedo shape, and by this point the suspensor is degenerating and the shoot apical meristem and root apical meristem are established.
• Further growth of the cotyledons results in the torpedo and walking-stick stages, at which point embryogenesis is arrested, and the mature seed dessicates and remains dormant until germination.
• The sperm nuclei are derived from the pollen grains.
• Plant tissue cultures are generally initiated from multicellular tissue fragments, called explants, obtained from living plants.
• The suspensor develops from the basal cell and anchors the embryo to the endosperm, serving as a nutrient conduit for the developing embryo.
• These meristems will give rise to the adult structures of the plant upon germination.
• Further cell division leads to the globular stage, where the three basic tissue systems (dermal, ground, and vascular) can be recognized based on characteristic cell division patterns.
• A large amount of information on cell division patterns and organogenesis during embryo development has been accumulated based on descriptive studies.
• The sperm nuclei are derived from the pollen grains.
• In monocots, only a single cotyledon forms.
• Plant tissue culture depends upon totipotency, which is the ability of plant cells to regenerate into a whole plant.
• In double fertilization, one sperm nucleus fertilizes the egg, generating a 2N diploid zygote, while another sperm nucleus fertilizes a polar cell with two 1N nuclei, generating a 3N triploid endosperm.
• Tuberization is a complex phenomenon that involves a morphological transition of an underground shoot to stolon, subsequent tuber formation, and is under complex environmental, nutritional and endogenous regulation.
• Tuberization in potato serves dual function: as a storage organ and a means to vegetative propagation.