USES OF MANGANESE IN AGRICULTURE

MANGANESE

1. ACHARYA N.G. RANGA AGRICULTURAL UNIVERSITY AGRICULTURAL COLLEGE-BAPATLA COURSE NO:- AGRON 502 TOPIC : MANGANESE SUBMITTED BY- B.VENKATAKRISHNA BAM-18-09

2. Concentration in the earth’s crust averages 1000 ppm Indian soils ranges between 92 to 11500 ppm but soils contain 300 to 1600 ppm of Mn. Manganese when released through weathering of primary rocks will combine with O 2 , - and SiO 2 to form a number of secondary minerals including pyrolusite (MnO 2 ), manganite ( MnOOH ) and hausmannite (Mn 3 O 4 ) Forms of manganese are usually expressed as water soluble Mn 2+ , exchangeable Mn 2+ , water soluble and insoluble organically bound manganese, easily reducible manganese and manganese oxides. The principal ion species in solution is Mn 2+ and its concentration decreases 100 fold for each unit increase in pH . Importence of manganese

3. Factors affecting availability and movement of manganese Effect of pH and carbonates Excessive water and poor aeration Organic matter Imbalance of metal ions Interrelationship with other nutrients Seasonal and climatic effects Soil microorganisms Plant factors

4. Functions Healthy Mn sufficient mature plants contain 20 to 300 ppm of Mn Mn plays an important role in the photosynthesis and detoxification of superoxide free radicals Mn is an integral component of the water splitting enzyme associated with photosystem II Mn deficiency is associated with adverse effects on photosynthesis and O 2 evolution constituent of superoxide dismutase (Mn-SOD) Mn has a role in TCA cycle in oxidative and non oxidative decarboxylation reactions with Nicotine Adenine Diamide (NAD)

5. a major contributor to various biological systems including photosynthesis, respiration, and nitrogen assimilation. Involved in pollen germination, pollen tube growth. root cell elongation and resistance to root pathogens . plays an important role in plant lignin and phenol synthesis That structural components of the sclerenchyma are less developed under Mn -deficient conditions than under non-limiting conditions. Polle and Chakrabarti (1994) found less cell wall material but similar lignin content in Mn -deficient  Involved in activating enzyme-catalysed reactions including phosphorylations , decarboxylations , reductions and hydrolysis reactions and therefore affects processes such as respiration, amino acid synthesis, lignin biosynthesis and the level of hormones in plants.  PHYSIOLOGICAL FUNCTIONS

6. Effect of Manganese on plant carbohydrates and lignin content of plant marschner (2012)

7. Manganese deficiency symptoms, which often look like those of iron deficiency, appear as interveinal chlorosis (yellow leaves with green veins) on the young leaves, tan , sunken spots that appear in the chlorotic areas between the veins. Plant growth may also be reduced and stunted. Manganese deficiency can occur when the pH of the growing medium exceeds 6.5, because it is tied up and unavailable for uptake. Deficiency can also occur from low fertilizer application rates, use of general purpose fertilizers (which typically have reduced micronutrient contents ), excessive leaching or applying too many iron chelate drenches. Deficiency symptoms

8. Mn deficient plants contain less than 25 ppm more severe on middle leaves than on the younger ones Interveinal chlorosis in dicotyledons Grey speck of Oats Speckled yellow of sugar beet Marsh spot of peas Pahala blight of sugar cane Frenching of tung grass

9. burning of the tips and margins of older leaves or as reddish-brown spots across older leaves. Severe toxicity may result in spots becoming more numerous and larger, forming patches on the older leaves. At pH levels below 5.5, manganese is very soluble and toxicity symptoms are probable, especially in zonal geraniums, marigolds and New Guinea Impatiens. Manganese toxicity can occur if the fertilizer application rate is excessive. Toxicity

10. Corrective measures Soil application of Mn SO 4 . 3 H 2 O (26-28 % Mn) @ 10-25 kg/ha Mn SO 4 H 2 O (30-32 % Mn) @ 10-25 kg/ha Application of green manures FYM and other organic manures

11. The main sources of manganese fertilizer

12. MANGANESE AS ESSENTIAL AND TOXIC ELEMENT FOR PLANTS: TRANSPORT, ACCUMULATION AND RESISTANCE MECHANISMS Millaleo at al., ( 2009) J. Soil Sci. Plant Nutr . 10 (4): 476 - 494 (2010)

13. Upper panel: photobleaching effects on sugar maple leaves exposed to elevated Mn . Lower panel: the influence of Mn availability and light intensity (1500 and 500 μmol m −2 s −1 ) on the light and dark reactions of photosynthesis (CER, ETR) and chlorophyll  a  +  b in sugar maple leaves Manganese phytotoxicity : new light on an old problem Fernando

14. Assessment of Some Mineral Elements (Ca, Na, K, Mg, Fe, Mn Cu and Zn) and their Nutritional Intake of Two Traditional Leafy Vegetables: Leaves of Corchorus Olitotorius ( Tiliaceae ) and Hibiscus Sabdariffa ( Malvaceae ) Alexis Drogba Sahore et al.,(2014) International Journal of Agriculture Innovations and Research Volume 3, Issue 3, ISSN (Online) 2319-1473

15. Devi et al.,(2005)