i would like to know the importance of calcium nitrate to plant . i know that this fertilizer is made up of two nutrients : nitrate and soluble calcium . a biochimical response should be appreciated to know how green plants uses these two nutrients . thanks.
Hi Maher,
Calcium nitrate is the preferred inorganic N fertilizer source where soil acidification is undesirable and when both calcium and nitrogen are required to be supplied at the same time.
Susantha.
Yes to Samantha Jayasundara's answer (non acidifying as compared to ammonium-nitrogen fertilisers such as ammonium phosphates and particularly ammonium sulphate. Other options where soil acidification is undesirable are calcium ammonium nitrate or applying calcium as gypsum or lime (with nitrogen applied additonally. Calcium nitrate also has an advantage for foliar fertilizer use being a soluble form of calcium. This is very useful in some tree crops including apples for which it can otherwise be hard to increase calcium levels.
With respect to the initial broad question, of the role of calcium and nitrate, a non-exhaustive list of roles of these major plant nutrients are:
Calcium Roles: Cell wall and general structure (particularly high levels in the middle lamella). Cell membrane function in nutrient transport. Nutrient uptake. Protection from aluminium and manganese toxicity. Plant defence responses. Improved photosynthesis. Root growth, elongation, mycorrhizal fungal promotion, root mucilage production (increasing root contact with soil). Regulating enzyme systems. Water regulation and nutrient balance in plant tissue. Legume nodule structure and nitrogen fixation.
Calcium helps activate cellular repair and plant defence mechanisms including selective cell death in advance of a potentially invasive disease that requires living cells and defence chemicals (e.g. phenolics and phytoalexins). High calcium levels also assist plant cells to with the formation of callose, plant cells providing protective barriers to injured plant parts. Calcium improves the function of antioxidants, protecting plant cells from biochemical stresses of cell damage.
Calcium deficiency results in structure disintegration such as leaf tip burn, dying ends of shoots, detaching leaf stalks, blossom-end rot (in tomatoes and members of the cucumber family), bitter pit (in apples), increasing risk of pests and disease entry. The symptoms reflect the importance of calcium in cell structure but also the protective role of calcium against one of the plant’s own enzymes that breaks down the pectin layer between cells.
Nitrate: Needs to be reduced to ammonium (occurs within the roots and shoots of plants and in mycorrhizal fungi). The ammonium is then the source of nitrogen for amino acid formation and thus all proteins (including enzymes) required by the plant. Many other plant compounds require nitrogen also such as DNA, RNA, ATP, hormones.
Calcium nitrate is a very soluble fertilizer and is a common source of both nutrients in foliar application, specially when Ca is needed, as it occurs with some crops as tomato and apples.
Its application to soil probably needs to be restricted to situations when you want a very fast effect of N and with no rainfall. As all the N is in a NO3 form, other situations may result in high risks of N leaching, with economical and environmental consequences.
For Ca application to soils, we may use amendments such as Ca carbonate.
Hi Maher: Both calcium and nitrates are essential elements for plants. In the soil Calcium is an active partipante in the cation exchange and nitrate anion can be a pemanecer in soil solution being absorbed or leached to lower layers. A nutritional status in saline soils or boron are recommended high concentrations of calcium nitrate as NO3 is antagonistic with borates and chlorides, while calcium is antagonistic with sodium. The pH of the calcium nitrate solution of 6.5 so his reaction is acid.
Interesting answers . We have tested the effect of calcium nitrate in citrus as 1.0% . Its quite impactful , since citrus requires much higher quantity of calcium than any other nutrients , if nutrient removal pattern by fruits is followed closely. Soils having better calcium saturation level on the exchange complex , produced much better peel color ( Higher ratio orange red to green color ) , tighter fruits and better shine on the peel , besides the better size. Physiological maturity of the fruits , evident from higher TSS/Acid ratio. Calcium nitrate has also shown equally good response through fertigation than foliar spray . However , better efficacy of calcium nitrate is obtained only when , there is no deficiency of boron .
Thanks Maher. Another very intriguing issue regarding calcium nutrition of plant , i missed in my earlier communication , is the tripartite relation between calcium , magnesium and potassium . Potassium on one hand , is balanced by concentration of calcium and magnesium on the other hand . This relation operates at both the levels, soil and in plants system. Soils rich in exchangeable-K, especially in those soils having illitic mineralogy , excess of k has to be balanced by addition application of Ca plus Mg , if the maximum response of these nutrients has to be harnessed.
- Badges
- Science topic
- Similar topics
- Phytochemistry
- Extracts