This article throws light upon the top five theories of ion uptake by plants. The theories are: 1. Lundegardh Theory 2. Contact Exchange Theory 3. Carbonic Acid Exchange Theory 4. Bennet-Clark's Protein Lecithin Theory 5. Donnans' Equilibrium Theory. 1. Lundegardh Theory (Electro-Chemical Theory) of Ion Uptake: Lundegardh (1945) proposed that an electrical potential gradient existing between the cell membrane of [...]
After reading this article you will learn about:- 1. Meaning of Chelates 2. Reaction of Organic Matter and Metal Ions 3. Stability of Chelates 4. Practical Implications in Chelation Reactions in Soils. Meaning of Chelates: The term "Chelate" is derived from a Greek word which means as a type of chemical compound in which a metallic ion is firmly combined [...]
After reading this article you will learn about nitrogen in relation to physiology, growth and response of crops. Nitrogen in Relation to Physiology of Plants Nitrate (NO3—N) and ammonium (NH4—N) are two major forms of inorganic nitrogen taken up by the plants. Most of the ammonium has to be incorporated into organic compounds in the plant roots, whereas nitrate is [...]