Lecture 11 Mineral Nutrition In Plants PDF

Machine Translated by Google L.11 Biology Department SQU College of Science Lecture 11 BIOL301...

Machine Translated by Google L.11 Biology Department SQU College of Science Lecture 11 BIOL3011 Mineral nutrition in plants Plant Physiology Machine Translated by Google L.11 Biology Department SQU College of Science Understanding of the mechanisms by which plants absorb and Outcome utilize nutrients, the role of essential and non-essential elements in plant metabolism, and methods such as hydroponics and sand culture for studying mineral nutrition. Plant Physiology Machine Translated by Google L.11 Biology Department SQU College of Science 1 Introduction to mineral nutritions 2 Essentials and non-essentials elements in plants Outline 3 Methods of studying mineral nutrition 4 Nutrient solutions for plant cultivation 5 Challenges in diagnosing nutrient deficiencies Plant Physiology Machine Translated by Google 1 Introduction to mineral nutritions 1  Introduction to mineral nutritions Machine Translated by Google 1 ÿNutrition is the process by which living organisms absorb and utilize raw materials to support their life processes, including growth and reproduction. ÿNutritional requirements for plants: Plants require a wide range of substances from their external environment to live and grow, collectively known as nutrition. ÿ This supply is critical for their metabolic activities, growth, and development. ÿ Types of nutritional requirements: 1.Organic Nutrients: These include carbon-based compounds that plants either synthesize or obtain from their environment. 2. Inorganic Nutrients: These consist of minerals and elements absorbed from the soil, which are essential for plant metabolism, structural integrity, and other physiological functions.  Introduction to mineral nutritions Machine Translated by Google 1 Types of nutrition ÿ Based on this nutrition may be classified into two types: ÿHeterotrophic nutrition: requires both organic and inorganic elements. Autotrophic nutrition: requires only inorganic elements. Plants are photo-autotrophs. Machine Translated by Google 2 Essentials and non-essentials elements in plants 2  Essentials and non-essentials elements in plants Machine Translated by Google 2 ÿPlant nutrient analysis: The analysis of plants reveals that they may contain over 60 different elements. The specific number of elements present can vary from plant to plant. ÿClassification based on essentiality: Essential elements: These are crucial for plant metabolism and are required for normal growth and development. There are 16 essential elements. Non-essential elements: These elements do not play a direct role in metabolism and are not strictly necessary for the plant's survival.  Essentials and non-essentials elements in plants Machine Translated by Google 2 Classification of elements ÿTo determine which element is essential for plant growth, the plant is grown in the absence of that specific element. ÿIf the element is essential, its absence will severely affect the plant's growth and reproduction. ÿEssential elements are specific and cannot be replaced by another element. ÿThe effects of the absence of an essential element are direct and not due to interactions with other factors.  Essentials and non-essentials elements in plants Machine Translated by Google 2 Functions of essential elements in plant physiology 1. Constituents of compounds C, H, O make carbohydrates, proteins, lipids. 2. Activation of enzymes Fe, Cu, Zn, Mn (catalytic reactions). 3. Osmoregulation of cells: Na+, K+, Ca++, Mg++, Cl- 4. Synthesis of Nucleic acids: N, S, P 5. Synthesis of Cell wall: Calcium (Modify permeability of membranes)  Essentials and non-essentials elements in plants Machine Translated by Google 2 Functions of essential elements in plant physiology ÿDepending on the quantity of requirement the essential elements are classified into: ÿMacronutrients: (9) Essential elements required in large quantity (C, N, O, Ca, H, K, Mg, P, S). ÿMicronutrients: (7) Essential elements required in minute quantity (Fe, Mn, Cu, Zn, Mo, B, Cl) ÿNon-essential elements: Only certain plants require them. eg Sodium Na by C4 plants and halophytes, Silicon Si for grasses.  Essentials and non-essentials elements in plants Machine Translated by Google 2 Machine Translated by Google 3 Methods of studying mineral nutrition 3 Machine Translated by Google 3 Methods of studying mineral nutrition ÿMethods to Study Mineral Nutrition 1.Plant analysis and content analysis 2.Solution culture, including hydroponics and aeroponics 3. Sand culture techniques Machine Translated by Google 3 Methods of Studying Mineral Nutrition 1. Plant analysis and ash content analysis ÿDetermines the total mineral content of plant tissues. This is crucial for understanding nutrient uptake and deficiencies. Ashing at 600°C removes organic matter, leaving only inorganic minerals. The remaining ash is analyzed using chemical or instrumental methods to quantify mineral content. ÿStudy the ash content (Spectrophotometry, Turbidimetric Methods, Titrimetric Methods Machine Translated by Google 3 Methods of studying mineral nutrition 2. Solution culture, including hydroponics and aeroponics ÿPlants are grown in nutrient solutions without soil. ÿ To study the effect of individual nutrients by manipulating the composition of the solution. ÿEffective for controlled experiments but not always representative of natural soil conditions. Machine Translated by Google 3 Methods of studying mineral nutrition 2.Hydroponics Machine Translated by Google 3 Methods of studying mineral nutrition Hydroponics Hydroponic Lettuce Machine Translated by Google 3 Methods of studying mineral nutrition 2.Aeroponics Machine Translated by Google 3 Methods of studying mineral nutrition Aeroponics Aeroponic strawberry Machine Translated by Google 3 Methods of studying mineral nutrition Active learning (Video) hydroponic vs aeroponic https://www.youtube.com/watch?v=IInjYsqRXmg Machine Translated by Google 3 Methods of studying mineral nutrition 3. Sand culture techniques ÿSand culture provides support to the plant and also provides air. ÿ Plants are grown in sterilized sand, and nutrient solutions are supplied periodically. ÿ Allows root aeration while providing precise nutrient control. ÿ Useful for experiments where root interactions with substrates need to be minimized. Ma et al., 2022 (Agronomy 12:664) Machine Translated by Google 4 Nutrient solutions for plant cultivation ÿNutrient medium is of two types: Complete solution: contains all essential macro and micronutrients. Also called as balanced nutrient solution eg Hoagland solution; Knops solution and Arnon's solution. Incomplete solution: solution which misses a single element. Elimination of a single element at a time. Machine Translated by Google 4 Nutrient solutions for plant cultivation Knop's solution: contain KNO3 , Ca(NO3)2 , H2PO4 , MgSO4 and Iron salt. Hoagland solution: Has all the mineral elements for rapid plant growth. Arnon's solution: Macronutrients and micronutrients. In these solutions the conc. The elements are high but do not produce toxic symptoms or salinity stress. eg PO4 in soil is 0.06 ppm but in H. solution it is 62 ppm Nitrogen is supplied both as ammonium NH4+ and nitrate NO3 - Machine Translated by Google 4 Nutrient solutions for plant cultivation There is a balance of cations and anions. Make sure that the pH does not rise. Inorganic forms of iron can precipitate as iron hydroxide and hence not available to plant Iron phosphates are not soluble, so organic form of iron is used with a chelating agent Chelating agent: form soluble complexes with cations. eg citric acid, tartaric acid, EDTA (ethylenediamine tetra acetic acid). Iron is released from the chelator when it is reduced from Fe3+ to Fe2+ at the root surface Machine Translated by Google 5 Challenges in diagnosing nutrient deficiencies ÿIt is difficult to diagnose nutrient deficient symptoms when plants are grown in soil because ÿSeveral elements may be deficient at one time. ÿExcessive amount of one element may induce deficiency of another. ÿSome Virus disease symptoms may be similar to nutrient deficiency.