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Deficiency, boron

Approximately 5% of the U.S. consumption of is in agriculture. Boron is a necessary trace nutrient for plants and is added in small quantities to a number of fertilizers. Borates are also used in crop sprays for fast rehef of boron deficiency. Borates, when apphed at relatively high concentration, act as nonselective herbicides. Small quantities of borates are used in the manufacture of alloys and refractories (qv). Molten borates readily dissolve other metal oxides usage as a flux in metallurgy is an important apphcation. Other important small volume apphcations for borates are in fire retardants for both plastics and ceUulosic materials, in hydrocarbon fuels for fungus control, and in automotive antifreeze for corrosion control (see Corrosion and corrosion inhibitors). Borates are used as neutron absorbers in nuclear reactors. Several borates, which are registered with the Environmental Protection Agency (EPA) can be used for insecticidal purposes, eg, TIM-BOR. [Pg.205]

Boron deficiency on sweet corn overliming can disrupt the uptake by plants of this trace element... [Pg.87]

The addition of boron to boron-deficient plants induces rapid changes in membrane function that cannot be explained by the role of boron in cell walls described above. Although found in membrane fractions at much lower levels than in cell walls, boron is known to influence ion uptake. For example, uptake of phosphorus and potassium by the roots of various plant species, such as maize and sunflowers, is inhibited by boron deficiency. Uptake of these ions returns to normal within one hour after boron is restored [62]. [Pg.22]

Boron also appears to be involved in redox metabolism in cell membranes. Boron deficiency was shown to inhibit membrane H -ATPase isolated from plant roots, and H -ATPase-associated proton secretion is decreased in boron-deficient cell cultures [71]. Other studies show an effect of boron on membrane electron transport reactions and the stimulation of plasma reduced nicotinamide adenine dinucleotide (NADH) oxidase upon addition of boron to cell cultures [72, 73]. NADH oxidase in plasma membrane is believed to play a role in the reduction of ascorbate free radical to ascorbate [74]. One theory proposes that, by stimulating NADH oxidase to keep ascorbate reduced at the cell wall-membrane interface, the presence of boron is important in... [Pg.22]

It is now clear that earlier studies indicating that very low levels of boron are toxic to fish embryos were actually documenting the effects of boron deficiency [83]. More recent studies on fish show that embryonic growth is stimulated by boron in a dose-dependent manner [80]. While very high boron levels are toxic, insufficient boron levels (<9 pmol B) were shown to result in adverse effects on rainbow trout and zebrafish development. [Pg.24]

Deficiency of boron is a more prevalent worldwide agricultural problem than for any other agricultural micronutrient [62]. Adequate boron supplies are critical for maintaining high crop yields as well as good crop quality. For this reason it is common agricultural practice to apply boron-containing fertilizers in areas where soil boron deficiency is found. [Pg.33]

Boron deficiency is particularly prevalent in light-textured soils in which water-soluble borates are gradually leached down the soil profile and become unavailable to plants. Heavier, more loamy soils tend to retain more boron because they contain an abundance of compounds, such as humic acids, that can complex boron. Certain crop types have higher boron requirements and benefit most from supplementation. These include soybeans, cotton, peanuts, oil palm, apples, and almonds. [Pg.33]

No requirement for boron in mammals is proven, although evidence is accumulating suggesting that boron may be an essential nutrient. Boron is related to normal energy utilization, immune function, and metabolism of bone, minerals, and lipids (Penland 1998). Boron deficiency (<0.04... [Pg.1570]

More research is needed on the accurate measurement of boron in biological materials when the concentrations are <1.0 mg B/kg (Sullivan and Culver 1998). Standard biological reference materials with low boron levels need to be produced for use in interlaboratory comparisons. This becomes especially important in studies on boron-deficiency states and the ability of the organism to conserve boron at very low intakes (Sullivan and Culver 1998). More research is needed on homeostatic regulation of boron and functional markers of boron metabolism (Sutherland et al. 1998). Sullivan and Culver (1998) recommend additional studies to establish ... [Pg.1578]

Gupta, U.C. 1983. Boron deficiency and toxicity symptoms for several crops as related to tissue boron levels. Jour. Plant Nutr. 6 387-395. [Pg.1584]

Gupta, U.C. and J.A. Cutcliffe. 1985. Boron nutrition of carrots and table beets grown in a boron deficient soil. Comm. Soil Sci. Plant Anal. 16 509-516. [Pg.1584]

Hopmans, P. and D.W. Ehnn. 1984. Boron deficiency in Pinus radiata D. Don and the effect of applied boron on height growth and nutrient uptake. Plant Soil 79 295-298. [Pg.1585]

Lipsett, J., A. Pinkerton, and D.J. David. 1979. Boron deficiency as a factor in the reclamation by liming of a soil contaminated by mine waste. Environ. Pollut. 20 231-240. [Pg.1586]

Shorrocks, V.M. and D.D. Nicholson. 1980. The influence of boron deficiency on fruit quality. Acta Hortic. 92 103-108. [Pg.1588]

Smyth, D.A. and W.M. Dugger. 1980. Effects of boron deficiency on rubidium uptake and photosynthesis in the diatom Cylindrothecafusiformis. Plant Physiol. 66 692-695. [Pg.1588]

Stone, E.L. 1990. Boron deficiency and excess in forest trees a review. Forest Ecol. Manage. 37 49-75. [Pg.1588]

Willett, I.R., P. Jakobsen, and B.A. Zarcinas. 1985. Nitrogen-induced boron deficiency in lucerne. Plant Soil 86 443-446. [Pg.1589]

Biological Functions Although boron is required by plants, there is little solid evidence to date that it is required for the nutrition of livestock or humans. Boron deficiency may alter the levels of vitamins or sugars in... [Pg.252]

Roots with black, dead, hard spots in flesh. Cause Boron deficiency. Roots may be wrinkled or cracked. Plants can be stunted leaf edges may be brown and lower l af surfaces may be reddish purple. Preveitt deficiency problems by spraying plants with seaweed extract as soon as the first true leaves appear, and every few weeks thereafter. Check deficiency with a soil test. Correct by adding 1 tablespoon of borax dissolved in 1 gallon water, or 10 pounds of kelp, per 1(X) square feet of soil. [Pg.38]

Celery is a heavy feeder. Boron deficiency causes brown, mottled leaves and horizontal cracks on stalks. Florida 683 is tolerant of low boron. Calcium deficiency causes the center of the plant to blacken and die. Utah 52-70R Improved is tolerant of low calcium. Magnesium deficiency causes yellow leaves. Discolored streaks on stalks are a symptom of potassium deficiency. Phosphorus deficiency causes plants to form rosettes. Prevent problems by adding plenty of compost to the soil and by spraying plants with seaweed extract every 2 weeks. Check suspected deficiencies with soil tests and amend soil as needed. [Pg.63]

Ears with bare, undeveloped tips can also be caused by potassium deficiency. Phosphorus deficiency also causes small, irregular ears. See page 77 for an illustration of this condition. If ears are misshapen and kernels have corky, brown bands at their bases, suspect boron deficiency. Spray young plants with seaweed extract or compost tea to help prevent deficiencies. Confirm deficiencies with a soil test and amend soil as needed. [Pg.80]

Reports that boron deficiency increased nicotine production (436, 437) could not be confirmed in the writer s laboratory (Scholz, unpublished). Boron deficiency in Salsola richteri (190) and in Atropa (438) seemed to decrease alkaloid formation. There is a report that extra manganese and cobalt lead to increased alkaloid yields in Datura (439). [Pg.21]

The symptoms of plants treated with dichlobenil are very similar to symptoms of boron deficiency. After the inhibition of growth the apical meristems blacken and the plant dies. Sublethal doses of dichlobenil increase the chlorophyll content in the leaves of the treated plant, so that their colour becomes darker (Milborrow, 1964). [Pg.587]

The samples with expected compositions led to lower BET areas (typically less than ca. 30 m g ) than the boron deficient samples which exhibited BET area close to 70-80 nf/g (Table 1). These high BET values were attributed to the excess of alumina in the samples. [Pg.941]


See other pages where Deficiency, boron is mentioned: [Pg.272]    [Pg.148]    [Pg.185]    [Pg.21]    [Pg.22]    [Pg.23]    [Pg.24]    [Pg.1558]    [Pg.1558]    [Pg.1559]    [Pg.1562]    [Pg.1578]    [Pg.1579]    [Pg.1580]    [Pg.205]    [Pg.413]    [Pg.253]    [Pg.418]    [Pg.227]    [Pg.61]    [Pg.505]    [Pg.179]    [Pg.837]    [Pg.557]   
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See also in sourсe #XX -- [ Pg.294 ]

See also in sourсe #XX -- [ Pg.66 , Pg.69 , Pg.71 , Pg.72 , Pg.75 ]

See also in sourсe #XX -- [ Pg.70 ]

See also in sourсe #XX -- [ Pg.11 , Pg.795 ]




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Boron deficiencies attributed

Boron electron-deficient

Boron electron-deficient compounds

Boron electron-deficient molecules

Boron hydrides electron-deficient clusters

Boron, electron-deficient molecular

Boron, electron-deficient molecular compounds

Deficiency effects boron

Electron deficiency boron-rich solid

Electron-deficient clusters boron-containing

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