photomorphogenesis


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Photomorphogenesis

The regulatory effect of light on plant form, involving growth, development, and differentiation of cells, tissues, and organs. Morphogenic influences of light on plant form are quite different from light effects that nourish the plant through photosynthesis, since the former usually occur at much lower energy levels than are necessary for photosynthesis. Light serves as a trigger in photomorphogenesis, frequently resulting in energy expenditure orders of magnitude larger than the amount required to induce a given response. Photomorphogenic processes determine the nature and direction of a plant's growth and thus play a key role in its ecological adaptations to various environmental changes. See Photosynthesis

Morphogenically active radiation is known to control seed and spore germination, growth and development of stems and leaves, lateral root initiation, opening of the hypocotyl or epicotyl hook in seedlings, differentiation of the epidermis, formation of epidermal hairs, onset of flowering, formation of tracheary elements in the stem, and form changes in the gametophytic phase of ferns, to mention but a few of such known phenomena. Many nonmorphogenic processes in plants are also basically controlled by light independent of photosynthesis. Among these are chloroplast movement, biochemical reactions involved in the synthesis of flavonoids, anthocyanins, chlorophyll, and carotenoids, and leaf movements in certain legumes.

photomorphogenesis

[¦fōd·ō‚mȯr·fō′jen·ə·səs]
(botany)
The control exerted by light over growth, development, and differentiation of plants that is independent of photosynthesis.
References in periodicals archive ?
2014) and tiller angle (Sang, 2014); delaying leaf senescence and reducing secondary growth and controlling PCD (Programmed cell death), photomorphogenesis and modulating biotic/abiotic stress responses (Xiong et al.
2014) De Novo Transcriptome Assembly and Analyses of Gene Expression during Photomorphogenesis in Diploid Wheat Triticum monococcum.
Photoresponses including photosynthesis and photomorphogenesis are biological reactions essential for growth of vegetables.
These changes observed in the seedlings are results of photomorphogenesis, where low intensity and/ or light quality makes for greater growth and increase in the number of leaves as a strategy to meet the verified deficiency.
The constitutive photomorphogenesis 9 signalosome directs vascular endothelial growth factor production in tumor cells.
Among the topics are improving low-phosphate tolerance in crops, gene expression regulation in photomorphogenesis from the perspective of the central dogma, post-translationally modified small-peptide signals in plants, natural variations and genome-wide association studies in crop plants, and the molecular control of cell specification and cell differentiation during procambial development.
Key words: Photomorphogenesis, light, dark, callus, leafy vegetables.
The response includes photosynthesis and photomorphogenesis.
The temporal and spatial regulation of plant photomorphogenesis are regulated by light.