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Which form of N is most readily available for plant uptake? Is...
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Mark Werner
Which form of N is most readily available for plant uptake? Is...
Since N comes as NH4+ from two main sources, concentrated forms as either Urea, Ammonia, or Ammonium sulfate , and mineralizing organic matter, this form is abundant. However., under aerated condition in highlands, transformation to NO3- happens often. Being NH4+ available in soil, it is the same form as the transformation to NH4+ requires the availability of NH4+. Depending on the vegetation and root distribution NH4+ is rapidly absorbed by plants leaving negligible level for transformation.
Since N comes as NH4+ from two main sources, concentrated forms as either Urea, Ammonia, or Ammonium sulfate , and mineralizing organic matter, this form is abundant. However., under aerated condition in highlands, transformation to NO3- happens often. Being NH4+ available in soil, it is the same form as the transformation to NH4+ requires the availability of NH4+. Depending on the vegetation and root distribution NH4+ is rapidly absorbed by plants leaving negligible level for transformation.
The NO3- ion is vulnerable to leaching due to its negativity but can even reach such leached ions to the root surface through mass flow depending upon soil moisture status, environmental condition (warm or cool), type of plants, and rates of ET, etc. On the other hand, NH4+ is a cation that is adsorbed onto colloids, and hence it may be available to plant roots longer duration than NO3- depending upon the type of soil. The way the question has been asked, obviously one would say NO3- that will be fast absorbed by plants compared to NH4+ if it remains available. NO3- is vulnerable to leaching depending upon the rate of downward water movement, rainfall, or irrigation. In oxidized soils (upland soils) NH4+ is oxidized to NO3- and hence the latter would be abundant. In reduced soils (poorly drained and rice soils), the former remains abundant. In that situation, NH4+ remaining adsorbed on cation exchange complex would be available for plant roots to exchange over a longer period compared to NO3- that may remain for a short period until the soil solution stays. Since the way, the root getting contact with ions determines the rate of absorption. It is governed by many factors. Isolated conditions could not be found in soil environments to point out which would be taken up faster. NO3- is in soil solution whereas NH4+ is adsorbed on cation exchange complex. One would be able to compare the rates of uptake of preference using control experiments using hydroponic systems in which the nutrients will remain only in the solution with no cation exchange complexes.
The NO3- ion is vulnerable to leaching due to its negativity but can even reach such leached ions to the root surface through mass flow depending upon soil moisture status, environmental condition (warm or cool), type of plants, and rates of ET, etc. On the other hand, NH4+ is a cation that is adsorbed onto colloids, and hence it may be available to plant roots longer duration than NO3- depending upon the type of soil. The way the question has been asked, obviously one would say NO3- that will be fast absorbed by plants compared to NH4+ if it remains available. NO3- is vulnerable to leaching depending upon the rate of downward water movement, rainfall, or irrigation. In oxidized soils (upland soils) NH4+ is oxidized to NO3- and hence the latter would be abundant. In reduced soils (poorly drained and rice soils), the former remains abundant. In that situation, NH4+ remaining adsorbed on cation exchange complex would be available for plant roots to exchange over a longer period compared to NO3- that may remain for a short period until the soil solution stays. Since the way, the root getting contact with ions determines the rate of absorption. It is governed by many factors. Isolated conditions could not be found in soil environments to point out which would be taken up faster. NO3- is in soil solution whereas NH4+ is adsorbed on cation exchange complex. One would be able to compare the rates of uptake of preference using control experiments using hydroponic systems in which the nutrients will remain only in the solution with no cation exchange complexes.
Plants can utilize both nitrate and ammonium forms of nitrogen with equal ease. It all depends upon which form is more available in a given environment. For example, in submerged rice it is ammonium which is more available in the soil. Whether nitrates are not formed or lost under anaerobic conditions is a different issue. In upland crops like wheat, nitrate-N are not preferred because it is nitrate-N, but because ammonium-N is readily converted to nitrate-N. I would like to repeat - - plants can use both nitrate- and ammonium-N with equal ease.
Plants can utilize both nitrate and ammonium forms of nitrogen with equal ease. It all depends upon which form is more available in a given environment. For example, in submerged rice it is ammonium which is more available in the soil. Whether nitrates are not formed or lost under anaerobic conditions is a different issue. In upland crops like wheat, nitrate-N are not preferred because it is nitrate-N, but because ammonium-N is readily converted to nitrate-N. I would like to repeat - - plants can use both nitrate- and ammonium-N with equal ease.
The assimilation of NH4+ is more energetically efficient when compared with NO3-, because NH4+ can be directly incorporated into glutamate via an NH4+ assimilation pathway. Nitrate, on the other hand, must first be modified via a reduction pathway before assimilation. However, NO3- is usually more available for uptake in many ecosystems, owing to its higher mobility. Nitrate can be incorporated into organic compounds in both root and leaf tissues whereas NH4+ is only synthesized into amino acids in the root tissues near the site of uptake to avoid toxic accumulation. Either NH4+ or NO3- can dominate the inorganic N pool of an ecosystem. For example, in most mature undisturbed forests, the soil inorganic N pools are dominated by NH4+. In well aerated agricultural soils or other frequently disturbed sites, NO3- is the principal inorganic N source. According to Tisdale et al. (1993, Soil Fertility and Fertilizers), the rate of NO3- uptake is usually high and is favored by low-pH conditions. NH4+ uptake proceeds best at neutral pH values and is depressed by increasing acidity. Marchner (1995, Mineral Nutrition of Higher Plants), states that higher growth rates are achieved with mixed supply of both form of nitrogen. When both forms of N are supplied, it is easier for the plant to regulate intracellylar pH and to store some of the N at low energy costs. Marschner (1995) also states that the higher C demand for ammonium assimilation in roots, compared with nitrate-fed plants is associated with higher O2 consumption in roots. Accordingly, plant growth, particularly root growth, is poor in ammonium-fed plants when both root zone temperature and ammonium concentration are high. The suitability of ammonium for achieving high growth rates and yield therefore depends on root zone temperature plus other factors which determine carbohydrate supply to the roots (e.g. light intensity). Nitrate is a storage form in plants with no necessity to be assimilated in the roots, although it has to be reduced before assimilation which is an energy demanding process.
The assimilation of NH4+ is more energetically efficient when compared with NO3-, because NH4+ can be directly incorporated into glutamate via an NH4+ assimilation pathway. Nitrate, on the other hand, must first be modified via a reduction pathway before assimilation. However, NO3- is usually more available for uptake in many ecosystems, owing to its higher mobility. Nitrate can be incorporated into organic compounds in both root and leaf tissues whereas NH4+ is only synthesized into amino acids in the root tissues near the site of uptake to avoid toxic accumulation. Either NH4+ or NO3- can dominate the inorganic N pool of an ecosystem. For example, in most mature undisturbed forests, the soil inorganic N pools are dominated by NH4+. In well aerated agricultural soils or other frequently disturbed sites, NO3- is the principal inorganic N source. According to Tisdale et al. (1993, Soil Fertility and Fertilizers), the rate of NO3- uptake is usually high and is favored by low-pH conditions. NH4+ uptake proceeds best at neutral pH values and is depressed by increasing acidity. Marchner (1995, Mineral Nutrition of Higher Plants), states that higher growth rates are achieved with mixed supply of both form of nitrogen. When both forms of N are supplied, it is easier for the plant to regulate intracellylar pH and to store some of the N at low energy costs. Marschner (1995) also states that the higher C demand for ammonium assimilation in roots, compared with nitrate-fed plants is associated with higher O2 consumption in roots. Accordingly, plant growth, particularly root growth, is poor in ammonium-fed plants when both root zone temperature and ammonium concentration are high. The suitability of ammonium for achieving high growth rates and yield therefore depends on root zone temperature plus other factors which determine carbohydrate supply to the roots (e.g. light intensity). Nitrate is a storage form in plants with no necessity to be assimilated in the roots, although it has to be reduced before assimilation which is an energy demanding process.
Thank you all for your interesting answers. Would you please elaborate this sentence? "In upland crops like wheat, nitrate-N are not preferred because it is nitrate-N, but because ammonium-N is readily converted to nitrate-N." Do you mean 'ammonium-N is not preferred in upland crops ?
Thank you all for your interesting answers. Would you please elaborate this sentence? "In upland crops like wheat, nitrate-N are not preferred because it is nitrate-N, but because ammonium-N is readily converted to nitrate-N." Do you mean 'ammonium-N is not preferred in upland crops ?
This is very interesting question, but with no black and white answer to it. Let me mention some of the thoughts I came across while seeking answer to a similar question over the last three years. Because nitrate is much more mobile than ammonium, it is thought to be more likely accessible by plant roots than ammonium. There is also a view that the mobility of nitrate with soil solution makes it more prone to loss compared to ammonium, making it less available for plant uptake. The question about plant nitrate vs ammonium preference is also highly debated these days. Results from tracer studies suggest plants prefer nitrate to ammonium even though nitrate uptake and assimilation is more costly to plants. However, this assertation has been recently challenged, raising question how tracer results are interpreted. Other researchers argue that plants preference is related to adaptation, e.g., some conifers and crop plants such as rice that are adapted to acidic soil prefer ammonium. Then, there is also emerging evidence that plants likely use either N forms depending on its availability, which, in turn, is controlled by many factors, climate being one. So, we really do not have a clear answer to it. The following paper has some good answers to the above question: Chalk and Smith 2020 'On inorganic N uptake by vascular plants: Can 15N tracer techniques resolve the NH4+ versus NO3− “preference” conundrum? ArticleOn inorganic N uptake by vascular plants: Can 15N tracer tec...
This is very interesting question, but with no black and white answer to it. Let me mention some of the thoughts I came across while seeking answer to a similar question over the last three years. Because nitrate is much more mobile than ammonium, it is thought to be more likely accessible by plant roots than ammonium. There is also a view that the mobility of nitrate with soil solution makes it more prone to loss compared to ammonium, making it less available for plant uptake. The question about plant nitrate vs ammonium preference is also highly debated these days. Results from tracer studies suggest plants prefer nitrate to ammonium even though nitrate uptake and assimilation is more costly to plants. However, this assertation has been recently challenged, raising question how tracer results are interpreted. Other researchers argue that plants preference is related to adaptation, e.g., some conifers and crop plants such as rice that are adapted to acidic soil prefer ammonium. Then, there is also emerging evidence that plants likely use either N forms depending on its availability, which, in turn, is controlled by many factors, climate being one. So, we really do not have a clear answer to it. The following paper has some good answers to the above question: Chalk and Smith 2020 'On inorganic N uptake by vascular plants: Can 15N tracer techniques resolve the NH4+ versus NO3− “preference” conundrum? ArticleOn inorganic N uptake by vascular plants: Can 15N tracer tec...
The absorption of any of these forms depend on plant and soil conditions, many of them already considered. I would said that under optimal soil conditions the absorption of NO3 will be favored in plants with high photosynthetic capacity and no light restrictions. Those plants with low photosynthetic rates prefer more NH4 than NO3.
The absorption of any of these forms depend on plant and soil conditions, many of them already considered. I would said that under optimal soil conditions the absorption of NO3 will be favored in plants with high photosynthetic capacity and no light restrictions. Those plants with low photosynthetic rates prefer more NH4 than NO3.
Both nitrate and ammonium are uptaken by forest trees. However, ammonium is preferable to nitrate by trees in forest ecosystems if the amounts of the two nutrients close each other. In case ammonium is high in the soil, nitrate uptake is inhibited. The amount of the nutrients depend on environmental conditions due to the effects of them on ecological processes such as nitrification and ammonification. The uptake of the nitrohen form also can change with tree species.
Both nitrate and ammonium are uptaken by forest trees. However, ammonium is preferable to nitrate by trees in forest ecosystems if the amounts of the two nutrients close each other. In case ammonium is high in the soil, nitrate uptake is inhibited. The amount of the nutrients depend on environmental conditions due to the effects of them on ecological processes such as nitrification and ammonification. The uptake of the nitrohen form also can change with tree species.
An excellent answer from Konstantinos; however I have a little extra to add. This question is very specific to plant species, Blueberries for example have very low nitrate reductase activity and therefore are almost totally dependent on ammonium as the nitrogen source. Conversely the monocots especially grasses appear to be comfortable in utilizing nitrate.
An excellent answer from Konstantinos; however I have a little extra to add. This question is very specific to plant species, Blueberries for example have very low nitrate reductase activity and therefore are almost totally dependent on ammonium as the nitrogen source. Conversely the monocots especially grasses appear to be comfortable in utilizing nitrate.
Under oxidize zone, nitrate nitrogen is taken by plant. Under reduced condition, ammonical nitrogen prefer by plant. Rice, potato, beetle vine banana taken it both the form of nitrogen, depend upon soil refox potential. Regards
Under oxidize zone, nitrate nitrogen is taken by plant. Under reduced condition, ammonical nitrogen prefer by plant. Rice, potato, beetle vine banana taken it both the form of nitrogen, depend upon soil refox potential. Regards
Heiskanen, J. 2005. Effect of nitrate and ammonium on growth of transplanted Norway spruce seedlings: A greenhouse study. Annales Botanici Fennici 42: 1-9.
Heiskanen, J. 2005. Effect of nitrate and ammonium on growth of transplanted Norway spruce seedlings: A greenhouse study. Annales Botanici Fennici 42: 1-9.
Since N comes as NH4+ from two main sources, concentrated forms as either Urea, Ammonia, or Ammonium sulfate , and mineralizing organic matter, this form is abundant. However., under aerated condition in highlands, transformation to NO3- happens often. Being NH4+ available in soil, it is the same form as the transformation to NH4+ requires the availability of NH4+. Depending on the vegetation and root distribution NH4+ is rapidly absorbed by plants leaving negligible level for transformation.
Since N comes as NH4+ from two main sources, concentrated forms as either Urea, Ammonia, or Ammonium sulfate , and mineralizing organic matter, this form is abundant. However., under aerated condition in highlands, transformation to NO3- happens often. Being NH4+ available in soil, it is the same form as the transformation to NH4+ requires the availability of NH4+. Depending on the vegetation and root distribution NH4+ is rapidly absorbed by plants leaving negligible level for transformation.
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The NO3- ion is vulnerable to leaching due to its negativity but can even reach such leached ions to the root surface through mass flow depending upon soil moisture status, environmental condition (warm or cool), type of plants, and rates of ET, etc. On the other hand, NH4+ is a cation that is adsorbed onto colloids, and hence it may be available to plant roots longer duration than NO3- depending upon the type of soil. The way the question has been asked, obviously one would say NO3- that will be fast absorbed by plants compared to NH4+ if it remains available. NO3- is vulnerable to leaching depending upon the rate of downward water movement, rainfall, or irrigation. In oxidized soils (upland soils) NH4+ is oxidized to NO3- and hence the latter would be abundant. In reduced soils (poorly drained and rice soils), the former remains abundant. In that situation, NH4+ remaining adsorbed on cation exchange complex would be available for plant roots to exchange over a longer period compared to NO3- that may remain for a short period until the soil solution stays. Since the way, the root getting contact with ions determines the rate of absorption. It is governed by many factors. Isolated conditions could not be found in soil environments to point out which would be taken up faster. NO3- is in soil solution whereas NH4+ is adsorbed on cation exchange complex. One would be able to compare the rates of uptake of preference using control experiments using hydroponic systems in which the nutrients will remain only in the solution with no cation exchange complexes.
The NO3- ion is vulnerable to leaching due to its negativity but can even reach such leached ions to the root surface through mass flow depending upon soil moisture status, environmental condition (warm or cool), type of plants, and rates of ET, etc. On the other hand, NH4+ is a cation that is adsorbed onto colloids, and hence it may be available to plant roots longer duration than NO3- depending upon the type of soil. The way the question has been asked, obviously one would say NO3- that will be fast absorbed by plants compared to NH4+ if it remains available. NO3- is vulnerable to leaching depending upon the rate of downward water movement, rainfall, or irrigation. In oxidized soils (upland soils) NH4+ is oxidized to NO3- and hence the latter would be abundant. In reduced soils (poorly drained and rice soils), the former remains abundant. In that situation, NH4+ remaining adsorbed on cation exchange complex would be available for plant roots to exchange over a longer period compared to NO3- that may remain for a short period until the soil solution stays. Since the way, the root getting contact with ions determines the rate of absorption. It is governed by many factors. Isolated conditions could not be found in soil environments to point out which would be taken up faster. NO3- is in soil solution whereas NH4+ is adsorbed on cation exchange complex. One would be able to compare the rates of uptake of preference using control experiments using hydroponic systems in which the nutrients will remain only in the solution with no cation exchange complexes.
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Plants can utilize both nitrate and ammonium forms of nitrogen with equal ease. It all depends upon which form is more available in a given environment. For example, in submerged rice it is ammonium which is more available in the soil. Whether nitrates are not formed or lost under anaerobic conditions is a different issue. In upland crops like wheat, nitrate-N are not preferred because it is nitrate-N, but because ammonium-N is readily converted to nitrate-N. I would like to repeat - - plants can use both nitrate- and ammonium-N with equal ease.
Plants can utilize both nitrate and ammonium forms of nitrogen with equal ease. It all depends upon which form is more available in a given environment. For example, in submerged rice it is ammonium which is more available in the soil. Whether nitrates are not formed or lost under anaerobic conditions is a different issue. In upland crops like wheat, nitrate-N are not preferred because it is nitrate-N, but because ammonium-N is readily converted to nitrate-N. I would like to repeat - - plants can use both nitrate- and ammonium-N with equal ease.
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The assimilation of NH4+ is more energetically efficient when compared with NO3-, because NH4+ can be directly incorporated into glutamate via an NH4+ assimilation pathway. Nitrate, on the other hand, must first be modified via a reduction pathway before assimilation. However, NO3- is usually more available for uptake in many ecosystems, owing to its higher mobility. Nitrate can be incorporated into organic compounds in both root and leaf tissues whereas NH4+ is only synthesized into amino acids in the root tissues near the site of uptake to avoid toxic accumulation. Either NH4+ or NO3- can dominate the inorganic N pool of an ecosystem. For example, in most mature undisturbed forests, the soil inorganic N pools are dominated by NH4+. In well aerated agricultural soils or other frequently disturbed sites, NO3- is the principal inorganic N source.
According to Tisdale et al. (1993, Soil Fertility and Fertilizers), the rate of NO3- uptake is usually high and is favored by low-pH conditions. NH4+ uptake proceeds best at neutral pH values and is depressed by increasing acidity.
Marchner (1995, Mineral Nutrition of Higher Plants), states that higher growth rates are achieved with mixed supply of both form of nitrogen. When both forms of N are supplied, it is easier for the plant to regulate intracellylar pH and to store some of the N at low energy costs.
Marschner (1995) also states that the higher C demand for ammonium assimilation in roots, compared with nitrate-fed plants is associated with higher O2 consumption in roots. Accordingly, plant growth, particularly root growth, is poor in ammonium-fed plants when both root zone temperature and ammonium concentration are high. The suitability of ammonium for achieving high growth rates and yield therefore depends on root zone temperature plus other factors which determine carbohydrate supply to the roots (e.g. light intensity). Nitrate is a storage form in plants with no necessity to be assimilated in the roots, although it has to be reduced before assimilation which is an energy demanding process.
The assimilation of NH4+ is more energetically efficient when compared with NO3-, because NH4+ can be directly incorporated into glutamate via an NH4+ assimilation pathway. Nitrate, on the other hand, must first be modified via a reduction pathway before assimilation. However, NO3- is usually more available for uptake in many ecosystems, owing to its higher mobility. Nitrate can be incorporated into organic compounds in both root and leaf tissues whereas NH4+ is only synthesized into amino acids in the root tissues near the site of uptake to avoid toxic accumulation. Either NH4+ or NO3- can dominate the inorganic N pool of an ecosystem. For example, in most mature undisturbed forests, the soil inorganic N pools are dominated by NH4+. In well aerated agricultural soils or other frequently disturbed sites, NO3- is the principal inorganic N source.
According to Tisdale et al. (1993, Soil Fertility and Fertilizers), the rate of NO3- uptake is usually high and is favored by low-pH conditions. NH4+ uptake proceeds best at neutral pH values and is depressed by increasing acidity.
Marchner (1995, Mineral Nutrition of Higher Plants), states that higher growth rates are achieved with mixed supply of both form of nitrogen. When both forms of N are supplied, it is easier for the plant to regulate intracellylar pH and to store some of the N at low energy costs.
Marschner (1995) also states that the higher C demand for ammonium assimilation in roots, compared with nitrate-fed plants is associated with higher O2 consumption in roots. Accordingly, plant growth, particularly root growth, is poor in ammonium-fed plants when both root zone temperature and ammonium concentration are high. The suitability of ammonium for achieving high growth rates and yield therefore depends on root zone temperature plus other factors which determine carbohydrate supply to the roots (e.g. light intensity). Nitrate is a storage form in plants with no necessity to be assimilated in the roots, although it has to be reduced before assimilation which is an energy demanding process.
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Dear Bijay,
Thank you all for your interesting answers. Would you please elaborate this sentence? "In upland crops like wheat, nitrate-N are not preferred because it is nitrate-N, but because ammonium-N is readily converted to nitrate-N." Do you mean 'ammonium-N is not preferred in upland crops ?
Dear Bijay,
Thank you all for your interesting answers. Would you please elaborate this sentence? "In upland crops like wheat, nitrate-N are not preferred because it is nitrate-N, but because ammonium-N is readily converted to nitrate-N." Do you mean 'ammonium-N is not preferred in upland crops ?
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It is already well documented that NH4-N forms are readily available as well as more quickly assimilated than any other forms of nitrogen
It is already well documented that NH4-N forms are readily available as well as more quickly assimilated than any other forms of nitrogen
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This is very interesting question, but with no black and white answer to it. Let me mention some of the thoughts I came across while seeking answer to a similar question over the last three years. Because nitrate is much more mobile than ammonium, it is thought to be more likely accessible by plant roots than ammonium. There is also a view that the mobility of nitrate with soil solution makes it more prone to loss compared to ammonium, making it less available for plant uptake. The question about plant nitrate vs ammonium preference is also highly debated these days. Results from tracer studies suggest plants prefer nitrate to ammonium even though nitrate uptake and assimilation is more costly to plants. However, this assertation has been recently challenged, raising question how tracer results are interpreted. Other researchers argue that plants preference is related to adaptation, e.g., some conifers and crop plants such as rice that are adapted to acidic soil prefer ammonium. Then, there is also emerging evidence that plants likely use either N forms depending on its availability, which, in turn, is controlled by many factors, climate being one. So, we really do not have a clear answer to it. The following paper has some good answers to the above question:
Chalk and Smith 2020 'On inorganic N uptake by vascular plants: Can 15N tracer techniques resolve the NH4+ versus NO3− “preference” conundrum? Article On inorganic N uptake by vascular plants: Can 15N tracer tec...
This is very interesting question, but with no black and white answer to it. Let me mention some of the thoughts I came across while seeking answer to a similar question over the last three years. Because nitrate is much more mobile than ammonium, it is thought to be more likely accessible by plant roots than ammonium. There is also a view that the mobility of nitrate with soil solution makes it more prone to loss compared to ammonium, making it less available for plant uptake. The question about plant nitrate vs ammonium preference is also highly debated these days. Results from tracer studies suggest plants prefer nitrate to ammonium even though nitrate uptake and assimilation is more costly to plants. However, this assertation has been recently challenged, raising question how tracer results are interpreted. Other researchers argue that plants preference is related to adaptation, e.g., some conifers and crop plants such as rice that are adapted to acidic soil prefer ammonium. Then, there is also emerging evidence that plants likely use either N forms depending on its availability, which, in turn, is controlled by many factors, climate being one. So, we really do not have a clear answer to it. The following paper has some good answers to the above question:
Chalk and Smith 2020 'On inorganic N uptake by vascular plants: Can 15N tracer techniques resolve the NH4+ versus NO3− “preference” conundrum? Article On inorganic N uptake by vascular plants: Can 15N tracer tec...
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The absorption of any of these forms depend on plant and soil conditions, many of them already considered. I would said that under optimal soil conditions the absorption of NO3 will be favored in plants with high photosynthetic capacity and no light restrictions. Those plants with low photosynthetic rates prefer more NH4 than NO3.
The absorption of any of these forms depend on plant and soil conditions, many of them already considered. I would said that under optimal soil conditions the absorption of NO3 will be favored in plants with high photosynthetic capacity and no light restrictions. Those plants with low photosynthetic rates prefer more NH4 than NO3.
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Both nitrate and ammonium are uptaken by forest trees. However, ammonium is preferable to nitrate by trees in forest ecosystems if the amounts of the two nutrients close each other. In case ammonium is high in the soil, nitrate uptake is inhibited. The amount of the nutrients depend on environmental conditions due to the effects of them on ecological processes such as nitrification and ammonification. The uptake of the nitrohen form also can change with tree species.
Both nitrate and ammonium are uptaken by forest trees. However, ammonium is preferable to nitrate by trees in forest ecosystems if the amounts of the two nutrients close each other. In case ammonium is high in the soil, nitrate uptake is inhibited. The amount of the nutrients depend on environmental conditions due to the effects of them on ecological processes such as nitrification and ammonification. The uptake of the nitrohen form also can change with tree species.
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An excellent answer from Konstantinos; however I have a little extra to add. This question is very specific to plant species, Blueberries for example have very low nitrate reductase activity and therefore are almost totally dependent on ammonium as the nitrogen source. Conversely the monocots especially grasses appear to be comfortable in utilizing nitrate.
An excellent answer from Konstantinos; however I have a little extra to add. This question is very specific to plant species, Blueberries for example have very low nitrate reductase activity and therefore are almost totally dependent on ammonium as the nitrogen source. Conversely the monocots especially grasses appear to be comfortable in utilizing nitrate.
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Under oxidize zone, nitrate nitrogen is taken by plant. Under reduced condition, ammonical nitrogen prefer by plant. Rice, potato, beetle vine banana taken it both the form of nitrogen, depend upon soil refox potential. Regards
Under oxidize zone, nitrate nitrogen is taken by plant. Under reduced condition, ammonical nitrogen prefer by plant. Rice, potato, beetle vine banana taken it both the form of nitrogen, depend upon soil refox potential. Regards
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Heiskanen, J. 2005. Effect of nitrate and ammonium on growth of transplanted Norway spruce seedlings: A greenhouse study. Annales Botanici Fennici 42: 1-9.
Heiskanen, J. 2005. Effect of nitrate and ammonium on growth of transplanted Norway spruce seedlings: A greenhouse study. Annales Botanici Fennici 42: 1-9.
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