Nutrient deficiency systems Flashcards
-leaves are small and light green; lower leaves lighter than upper ones; not much leaf drop; weak stalks.
Nitrogen
-dark-green foliage; lower leaves sometimes yellow between veins; purplish color on leaves or petioles.
Phosphorus
-lower leaves may be mottled;
dead areas near tips and margins of leaves;
yellowing at leaf margins continuing toward center.
Potassium
-tip of the shoot dies; tips of young leaves die;
tips of leaves are hooked-shaped.
Calcium
-lower leaves are yellow between veins (veins remain green);
leaf margin may curl up or down or leaves may pucker;
leaves die in later stages.
Magnesium
-tip of the shoots stays alive;
light green upper leaves;
leaf veins lighter than surrounding areas.
Sulfur
-tip of the shoot stays alive; new upper leaves turn yellow between veins (large veins remain green); edges and tips of leaves may die.
Iron
-tip of the shoots stays alive; new upper leaves have dead spots over surface;
leaf may appear netted because of small veins remaining green.
Manganese
-tip of the shoot dies; stems and petioles are brittle.
Boron
-new and intermediate leaves are small, yellow, sometimes with grayish cast. Narrow and older leaves may drop. Small shoots may show resetting followed by dieback.
Zinc
developed by Dr. Cesar P. Mamaril in Phil Rice which involves the following treatment:
- complete/ with N, P, K, Zn
- minus N
- minus P
- minus K
- minus Zn
MOET/Minus-One Element Technique
determination of the nutrient content of a plant part or whole plant sampled at a specific stage of growth.
Plant Analysis
This method includes:
● field experiment
● pot experimentation
● microbiological test
Biological Test
comparison of several fertilizer treatments including a control using small amount of soil in pots to have better control of environmental factors.
Pot Experiment
it involves the use of microorganism to determine the presence of nutrients in the soil.
Microbiological Test
determination of the available amounts of nutrients in the soil or its chemical properties, followed by evaluation or interpretation and formulation of fertilizer recommendation.
Soil Testing or Soil Analysis
Classification/Manifestation of Symptoms:
- Complete crop failure
- Stunting
- Poor yield and quality
- Leaf discoloration
- Root stunting
Advantages of Using Nutrient Deficiency Symptoms in Soil Fertility Evaluation:
- Cheap; needs no elaborate equipment but require skill.
- Quick; needs no chemical analysis required to identify the problem.
Disadvantages of Using Nutrient Deficiency Symptoms in Soil Fertility Evaluation:
- Does not indicate the primary cause of the deficiency problem.
- It has problem in identifying what is really the problem; is it low in supply or poor assimilation?
- Does not indicate the amount needed to correct the limiting element.
- Deficiency can be relative to deficiency of one nutrient may be related to an excessive quantity of another or very low level of one can induce poor absorption
or utilization of other elements.
Disadvantages of Using Nutrient Deficiency Symptoms in Soil Fertility Evaluation:
- Hidden Hunger can occur and may cause misinterpretation of nutritional status.
- Many nutrients have chlorosis symptoms and these can overlap in advanced growth stages if not diagnosed early enough.
- It is difficult to distinguish among the deficiency symptoms in the field because disease or insects damage resemble certain micronutrient deficiencies.
- May be too late to correct the problem when the deficiency appears.
