Nutrient Interactions

some interactions

1. Excess of P adversely affects utilization of Zn, Fe and Cu

 2. Excess of Fe adversely affects utilization of Zn and Mn

 3. Excess of Zn, Mn, and Cu induces Fe-deficiency in crops

 4. Excess of S and Cu induces Mo-deficiency in crops

 5. Excess of Lime induces deficiency of all micronutrients.

 6. Presence of carbonate and bicarbonate ions in soil due to sodicity or over liming reduces the availability of micronutrient cations to crops which suffer most iron deficiency.

 7. Lime X P, Lime X Mo, Mo X P, and Na X K are common negative interactions.

 8. Excess of Ca may induce P deficiency

 9. Excess of Ca and Mg may depress K uptake

 10. Excess of Ca may reduce Mg uptake, if ratio is wider than 7:1

 11. Excess of K and NH+ may reduce Mg uptake

 12. Excess of N, K and Ca may reduce B toxicity

 13. Excess of N,P,K may induces Cu deficiency

14. Excess of NO3-N may cause Fe deficiency

Phosphorus Interactions with Other Nutrients

Nitrogen (N). Phosphorus and N are

both involved in vital plant functions such as photosynthesis, protein formation, and symbi- otic N fixation. The primary benefit from band placement of N and P fertilizers is greater Pptake because of increased P solubility and proximity to seedling roots. Also, ammo- niacal-N fertilizers can improve P availability to plants and thereby improve crop growth. Examples of positive N/P interactions are shown in Tables 1 and 2 Kansas research (Table 3) illustrates the beneficial influence of bal- anced NP fertilization on no-till grain orghum. Grain yield was increased by more than 13 bu/A, and the period from emergence to mid-bloom was shortened by seven days with proper use of N and P.

otassium (K). Phosphorus and K are both essential for photosynthesis, enzyme/ energy driven reactions, seed formation and quality, stress tolerance, crop maturity, etc. Research has documented cases of P/K inter- actions, (Tables 4, 5 and 6). They illustrate the agronomic and economic benefits of elim- inating P and K as limiting factors in crop production Balanced fertility is essential for high corn grain yields. Phosphorus and K each boosted grain yields in a study. Together, they increased grain yield by 64 bu/A, or 38 to 41 bu/A more than when each was applied alone (Table 7).

Sulfur (S). Research in California illus- trates the effects of a positive P/S interaction on increased forage production and the result- ing improved sheep performance due to improved yields and nutritive value of the for- age. Phosphorus alone did not increase lamb gain significantly, but the P/S interaction greatly increased production.

Magnesium (Mg). Phosphorus and Mg are essential for photosynthesis and seed for- mation. Crop uptake of both nutrients tends to decline under cold and wet soil conditions which sets the stage for nutrient interactions.

Micronutrients. Phosphorus interac- tions with micronutrients have been reported on a wide variety of crops. Interactions with P have been reported for B, copper (Cu), Fe, Mn, Mo, and Zn. Soils with high soil P levels (naturally or through buildup) should bemonitored for a possible micronutrient inter- action.

Boron. Phosphorus/B interactions caused a reduced B absorption by corn seedlings grown in an acid soil high in P. However, strawberries gave no significant interaction between P and B.

Copper. Phosphorus/Cu interaction was found when high levels of P accentuated an acute Cu deficiency in citrus seedlings. However, Cu and Zn solubili- ties can be increased by high levels of P fertilization. This interaction is believed to occur at the site of absorption…possi- bly with Cu precipitation at the root sur- face. In other studies, applied P reduced the effect of toxic levels of Cu. Excess Cu can decrease P and Fe absorption.

Iron. Phosphorus/Fe interaction showed up in bush beans grown in either an excess or deficient level of soil P. In either case, Fe absorption was reduced.

Both corn and rice, grown on soils con- taining excess Cu, exhibit severe Fe chlorosis. Heavy P fertilization is often recommended under such circum- stances.

Manganese. Phosphorus/Mn interac- tions can develop when soil Mn avail- ability increases with higher soil P levels. On some soils this is believed partially due to increased soil acidity from high rates of P.

Molybdenum. The P/Mo interaction depends upon whether the soil is alkaline or acidic in nature. For acidic soils, P increases Mo uptake while reducing Mo uptake on alkaline soils. The increase with acidic soils is believed to be the result of enhanced absorption and

translocation due to the H2PO – ion.

Zinc. Nutrient accumulation studies in corn have found P and Zn uptake, translocation, and deposition patterns to be quite similar. Research indicates the tendency of P to depress Zn nutrition is  physiological in nature and not due to inactivation in the soil. In high yield environments, negative interactions among micronutrients can develop. Results on corn in Kansas given in Table 8 illustrate how a negative response can be turned into a positive interaction with proper fertilization.

Potassium Interactions with Other Nutrients

potassium affects nitrate (NO3) absorption and reduction. Rapid NO3 uptake depends on adequate K in the soil solu- tion. Activity of the enzyme glutamine synthe- tase in wheat is lower when K is deficient. Potassium stimulates leaf protein synthe- sis. Up to 65 percent of the variability in grain quality traits, such as amino acid makeup, is due to non-genetic factors, including K nutrition. In a nutrient solution study, higher rates of K allowed for the efficient use of more nitrogen (N), which resulted in better early vegeta- tive growth and higher grain and straw yields as K and N rates increased. In the field, better N uptake and utilization with adequate K mean improved N use and higher yields. Crops respond to higher K levels when N is sufficient, and greater yield response to N fertilizer occurs when K is sufficient. Corn studies in Illinois and Ohio provide examples of this economically and environmentally impor- tant interaction (Figure 1).  

Potassium Uptake Nitrogen form can affect K absorption. For example, tomatoes grown in nutrient solution with NO3-N have shown a higher relative growth rate than plants supplied with ammonium-N (NH4-N). After 4 days, the total K content decreased in NH4-grown tomato plants and remained constant in those supplied with NO3. Similarly, when corn was grown with either NH4 or NO3 as the N source, both yield and total N uptake were lower with NH4-N as the source. However, when the high- est K rate was used, vegetative growth (yield) and N and K uptake were improved with the NH4-fed plants. It is clear that K interacts with N and is important in its utilization throughout the crop growth and yield production cycle.  

Potassium-Phosphorus Interactions Research has shown that K interacts with phosphorus (P) and that together they may inter- Text Box: Corn grain yield, bu/Aact with other nutrients. A good example is the observ- ed reduction of P-induced zinc (Zn) defi- ciency of corn when avail- able K levels are increased. Manganese (Mn) content of the corn plants    also INCREASING indicating there is some relationship of K, P, Mn, and Zn in this complex effect…resulting in less severe Zn deficiency. A more simple P-K interaction, but per- haps of more widespread importance, is their synergistic effect on yield (Tables 1 and 2). In these cases, besides their individual effects on yield, P and K together produced an extra 15 percent positive yield interaction for soybeans and 50 percent for Coastal bermuda- grass.  


Potassium, Calcium and Magnesium Interactions Low magnesium (Mg) or calcium (Ca) in forages can affect animals by producing low blood serum Mg or Ca (grass tetany). Incidence of tetany tends to be lower if for- age Mg exceeds 0.2 percent and Ca exceeds 0.4 percent. High plant K can have an antagonistic effect on Mg concentrations, particularly when Mg is low in soils. Seasonal changes in forage composition may be associated with factors such as levels and forms of N absorbed by plants. Absorption of NH4-N may result in greatly reduced uptake of Ca and Mg while having lesser effects on K. Large amounts of NH4-N in the soil would have the same effect on a forage as that of K, causing depressed uptake of Ca and Mg. Sudden rises in temperature tend to be associated with wider K/(Ca+Mg) ratios, which correspond with a higher grass tetany potential. Higher temperatures tend to increase the K uptake faster than that of Ca and Mg. Generally, additions of K, Ca or Mg result in a lower concentration of the remaining two cations, regardless of the crop grown. Research has shown that P fertilization of fescue pastures can significantly increase Mg and Ca contents of leaves early in the spring when the potential for tetany is highest.

Potassium/Sulfur Interactions Sulfur (S) nutrition of barley plants has an influence on the effect of K on Zn uptake from nutrient solutions. Apparently, good S levels along with adequate K improve Zn uptake.  

Potassium/Micronutrient Interactions Many interactions have been reported between K and micronutrients. Some of those reported with Zn (as they have involved P and S) have already been noted. Interactions with some of the micronutrients…boron (B), iron (Fe) and molybdenum (Mo)…have resulted in decreased uptake when K was added. For others…copper (Cu), Mn and Zn…use of K has increased micronutrient utilization. An interesting observed interaction is that between K and sodium (Na) on alfalfa. When K is deficient, the classical K deficiency symptom is quite apparent. However, for alfalfa grown on soils high in Na, the K deficiency symptom has a somewhat different appearance. See photos on page 21. The interactions between K and micronu- trients have not yet been well characterized. Further study, especially under field conditions, is necessary. Summary Potassium is known to interact with almost all of the essential macronutrients, secondary nutrients, and micronutrients. Future improve- ments in yield and quality will require a better understanding and management of these inter- actions. As livestock feeding operations, industrial uses, and food processors move to special vari- eties and identity-preserved marketing, nutrient effects on grain quality traits will become even more important.

Almost everything about Soil

Luxury consumption

  • It is the tendency of some crops to absorb and accumulate nutrients far in excess of their actual needs if it is present in sufficiently large quantities in the soil. Potassium is one of the nutrient elements which is subjected to luxury consumption.
  • The absorption pattern of different nutrients by plants is varies greatly among the plant species and also their age and growth stages.

Consumption of Nitrogen by plants

  • Plants absorb the N mostly in nitrate (NO3-) form or in ammonical (NH4+) form by some plants. Plants usually absorb the N more during active growing period, but they do not always absorb it at the same rate. The amount of nitrogen absorbed is at a maximum when the plants are young and gradually declines as the plants age. Plants can absorb extra nitrogen when it is available and store it to be used later if needed.
  • An oversupply of N generally produces dark green, succulent, vegetative growth. In such cases there will be a decline in seed production of grain crops, fruit production in tomatoes and some tree crops. In sugar beets, sugar content decreases and in and potatoes, tubers become watery. The negative effects of too much of N on growing plants can be lessened if the P and K supplies are adequate.
  • The average utilization of applied N by crops is around 50 percent but with proper nitrogen management strategies the efficiency as high as 80 % or more can be increased. Low N use efficiency may be attributed to various losses such as Volatilization of Ammonia in alkaline soil, Denitrification of Nitrate ions in flodded soil, Leaching loss of Nitrates in coarse textured soil, soil erosion/run off and ammonium fixation in clay lattices.

Consumption of phosphorus by plants

  • Phosphorus application, unlike N is known to benefit the growth and productivity of more than one crop in rotation. The residual P contributes more of P to crop nutrition. Responses to applied P depend on soil properties, initial available P, variety, level of N applied and management practices.
  • Phosphorus is absorbed as phosphate ions such as H2PO4- and HPO42- form. It is concentrated more in the reproductive parts of plant and in seeds. Harvested crops contain considerable amounts of P. In general, seed crops contain largest percentages of P, and forage crops contain moderate percentages.
  • Consumption of ‘P’ by the crops is very less after their application to soil and it accounts even less than 10 % and remaining amount will be useful later. This is mainly because; P is subjected to immobilization or fixation (retention/adsorption/precipitation/sorption) and undergoes various transformations which render it unavailable to plants.
  • P fertilizers are not easily and completely soluble in water and their mobility is less within the soil. Therefore in order to get maximum benefit from them we have to adopt suitable methods and time of application.

Consumption of potassium by plants

  • Potassium uptake is often equal to or more than that of nitrogen. It is absorbed by plants by K+ form. Crop species differ in their K requirement. Tuber crops like potato, vegetables like cauliflower and cabbage, forages like alfalfa and fruits like banana, grapes and pineapple, plantation crops like coconut, tea, rubber are among the heavy feeders of K.
  • High crop yields and higher rates of N and P application accelerate K uptake from the soil. Crop responses to K are large on laterites, red and yellow and mixed red and black soils. Plants absorb and accumulate K far in excess of their needs if it present sufficiently in soil without affecting the metabolic activity or without any plant response. This is called as Luxury consumption.
  • Potassium also subjected for various losses
    • 1) Leaching losses of K- Especially in sandy soils and soils rich in kaolinite located heavy rainfall area.
    • 2) Soil erosion losses- It also leads to considerable loss of total K from the soil.
    • 3) Fixation of K by clay complex of illite type

Consumption of secondary nutrients by plants

  • The amount of secondary nutrients removed by crops depends on the soil type, crop species, fertilizer sources and yield level. Generally, legumes and root crops remove more Ca and Mg than do cereals and other grasses. Cereals may remove 10-20 kg Ca per ha, a good crop of Brassica oleracea may remove 150 kg Ca per ha. A continuous cropping may result in the reduction of exchangeable Ca in soil.
  • Banana and pineapple crops with yield levels of 40 to 50 t/ha may remove 120 to 140 kg of Ca and Mg . As a thumb rule, S removal per tonne grain production can be taken as 3-4 kg for cereals, about 8 kg for pulses, about 12 kg for oil seeds and 18 kg for cruciferous and 38 kg for mustards. In most of the crop species, the critical limits of S in plants are 0.20 to 0.25%. Plants use approximately as much S as P.

Consumption of micro nutrients by plants

  • High crop yields remove substantial amounts of micronutrients from the soil, especially Zinc and Boron. Micronutrients depletion in soil depends on soil fertility level and crop yields. Maize based cropping sequence depletes the maximum micronutrients form soil, especially Zn and Fe.
  • The deficiencies of Zn and B are prevalent in most soils especially red and laterite soils.

Nutrient interactions in plants and soils

  • Interaction can be defined as the influence of an element upon another in relation to growth and crop yield. There may be positive or negative interaction of nutrients occurs either in soil or plant. The positive interaction of nutrients gives higher crop yield and such interactions should be exploited in increasing the crop production. Conversely, all negative interactions will lead to decline in crop yield and should be avoided in formulating agronomic packages for a crop.
  • The knowledge about interactions occurring in soils or plants or both is basic to help develop appropriate and efficient technologies. Further this will help to refine the existing ones to increase agricultural production.
  • There are mainly two types of interactions effect viz. antagonistic and synergistic effects. Antagonistic effect means an increase in concentration of any nutrient element will decrease the activity of another nutrient (negative effect). While synergistic effects means an increase of concentration of any one nutrient element will influence the activity of another nutrient element (Positive effect). One must understand how the negative or positive interaction takes place within or outside the plant.
  • The following antagonistic effects have been well established on the uptake of micronutrients by crops:
    • 1. Excess of P adversely affects utilization of Zn, Fe and Cu
    • 2. Excess of Fe adversely affects utilization of Zn and Mn
    • 3. Excess of Zn, Mn, and Cu induces Fe-deficiency in crops
    • 4. Excess of S and Cu induces Mo-deficiency in crops
    • 5. Excess of Lime induces deficiency of all micronutrients.
    • 6. Presence of carbonate and bicarbonate ions in soil due to sodicity or over liming reduces the availability of micronutrient cations to crops which suffer most iron deficiency.
    • 7. Lime X P, Lime X Mo, Mo X P, and Na X K are common negative interactions.
    • 8. Excess of Ca may induce P deficiency
    • 9. Excess of Ca and Mg may depress K uptake
    • 10. Excess of Ca may reduce Mg uptake, if ratio is wider than 7:1
    • 11. Excess of K and NH+ may reduce Mg uptake
    • 12. Excess of N, K and Ca may reduce B toxicity
    • 13. Excess of N,P,K may induces Cu deficiency
    • 14. Excess of NO3-N may cause Fe deficiency
  • (Lime: CaO, Ca(OH)2, CaCO3)

A little excursion to something i found to this topic.

The “Mineral Wheel”

  • It describes the influence of an excessive element on the uptake of other minerals.
  • There are 2 types:
    • antagonistic interactions
    • stimulating/synergizing interactions

This picture only shows antagonistic interactions:


“How to read”

  • If there is an arrow pointing from “Element1” to “Element2” it means
  • An excess of “Element1” leads to an uptake-problem or a deficiency of “Element2”.
  • Example: Fe -> Al | An excess of Fe leads to an uptake-problem or a deficiency of Al.

“Mulders Chart”


“How to read”

  • For the green Lines:
    • If there is an arrow pointing from “Element1” to “Element2” it means
  • An excess of “Element1” leads to an uptake-problem or a deficiency of “Element2”.
  • For the dotted Lines:
    • If there is an arrow pointing from “Element1” to “Element2” it means
  • An excess of “Element1” leads to a higher need of “Element2”.

Since these are a bit hard to read when u want to know a specific Element interaction I collected all data and wrote it down a excel file.

This is a screenshot of it:


“How to read”

  • On the right side is a info which sign goes for which element. Blue ones are essential ones.
  • Select your Element on the first row, then go down the coloum. On the left side you can the which element interaction it is.
  • Red fields are for antagonism, green fields for synergism, black fields are always the same element.
  • Example: (Mo)
    • Antagonism for: Ca, S, W
    • Synergism for: Cu, N