Nitrogen-fixing nodules on the roots of non-leguminous plants like Alnus are produced by
1. Rhizobium
2. Beijernickia
3. Azotobacter
4. Frankia

For each molecule of ammonia produced by nitrogenase, the number of ATP molecules required are:
1. 4
2. 8
3. 12
4. 16

The deficiency symptoms of iron, magnesium and calcium in plants may actually be due to the toxicity of
1. Potassium
2. Manganese
3. Iron
4. Chlorine

The criteria for essentiality of an element for a plant include all except:
1. It must be absolutely necessary for supporting normal growth and reproduction.
2. The requirement must be specific and not replaceable by another element.
3. It must be directly involved in the metabolism of the plant.
4. They must be present in the plants in a concentration in excess of 10 mmole/Kg of dry matter.

Identify the incorrectly matched pair:

Which of the following is not related to Julius Von Sachs?

1. A prominent German Botanist
2. In 1860, he demonstrated for the first time that plants could be grown to maturity in a defined nutrient solution in the complete absence of soil
3. The technique, Hydroponics
4. Categorized the essential and non-essential mineral nutrition.

Hydroponics can be used in

Hydroponics cannot be used in the commercial production of vegetables such as

Which of the following is the essential requirement of Hydroponics?

How many elements are found in plants?