Nutrient deficiency, plant responses

What the UDC-GV model has shown is that plants grown in nutrient-limited conditions could downregulate their growth rate in response to nutrient deficiency and still produce predictions that validate the model at least as well as the original analysis. It is extremely unlikely that the very simple and direct... 

Generally, nutrient deficiencies or excesses are caused by soil properties, fertilizer application, interactions between mineral elements during uptake and metabolism, and intrinsic factors of plants and crops with intensive nutrient responses. The rules of these element-specific influences were given by Bergmann (1992). 

Glutamine accumulation in mineral-deficient plants is less widely reported although this may reflect its greater instability during extraction compared to that of asparagine. However, glutamine accumulation can occur in response to deficiencies of most macro and micro nutrients, N and Mo excepted (Possingham, 1956 Steward et al., 1959). 

Arginine, like the amides, often accumulates in response to deficiencies of most macro and many micro nutrients (see Coleman, 1957 Hewitt and Smith, 1975). Achituv and Bar-Akiva (1978) suggest arginine accumulation is highly characteristic of P-deficient plants and have proposed that its accumulation in such plants is somehow related to a lack of pyridoxal phosphate which decreases the activity of aminotransferases (Achituv and Bar-Akiva, 1976, 1978). 

Phenolic compounds present in natural products include simple phenols, phenolic acids, tocopherols, stilbenes, coumarins, flavonoids (flavonol, flavones, flavanols, antho-cyanidins, proanthocyanidins), tannins, lignans, and lignins (Naczk and Shahidi, 2006 Folmer et ah, 2014). Phenolic compounds are secondary plant metabolites that are synthesized in response to stress conditions, such as UV irradiation, nutrient deficiencies, infection, and wounding (Naczk and Shahidi, 2006 Ramakrishna and Ravishankar, 2011). 

Soil Nutrient. Molybdenum has been widely used to increase crop productivity in many soils woddwide (see Fertilizers). It is the heaviest element needed for plant productivity and stimulates both nitrogen fixation and nitrate reduction (51,52). The effects are particularly significant in leguminous crops, where symbiotic bacteria responsible for nitrogen fixation provide the principal nitrogen input to the plant. Molybdenum deficiency is usually more prominent in acidic soils, where Mo(VI) is less soluble and more easily reduced to insoluble, and hence unavailable, forms. Above pH 7, the soluble anionic, and hence available, molybdate ion is the principal species. 

Root exudation of extraordinary high amounts of specific carboxy lutes (e.g ci-u-ate, malate. oxalate, pbytosiderophores) in response to nutritional deficiency stress or Al toxicity in some plant species cannot simply be attributed to diffusion processes. The controlled release of these compounds, involved in mobilization of mineral nutrients and in detoxification of Al. may be mediated by more specific mechanisms. Inhibitory effects by exogenous application of various anion chan-... 

The amount of strigolactones released from roots is drastically increased under deficiency of phosphate or nitrate in hosts of AM fungi 1015-1033. 1038,1039 thought to be an adaptive response of plants under nutrient... 

The book reviews our knowledge of the chemistry and mineralogy of Mo, the extraction of available Mo from various soils, the various analytical methods of determining Mo content in soils and plants, the biochemical role of Mo in crop production, the technology and application of Mo fertilizers to crops, the responses to Mo of various temperate and tropical crops. Mo deficiency and toxicity in various plant species, the interaction of Mo with other plant nutrients, and the distribution of Mo within the plant. Factors affecting the availability of soil Mo to plants and Mo status in the semiarid and subhumid tropics are also discussed. 

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