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

Which of the following is the essential requirement of Hydroponics?

Which of the following is the essential requirement of Hydroponics?

The soil is enriched of dissolved ions and inorganic salts because of

Which of the following is not true about soil?
P. Soil not only supplies minerals but also harbours nitrogen fixing bacteria and other microbes
Q. It holds water
R. It supplies air to the roots
S. It acts as a matrix that stabilises the plant
T. It is a source of photosynthate
U. It is positively geotropic without any exception

1. S, T and U
2. T and U
3. S and U
4. R and T

The soil is enriched of dissolved ions and inorganic salts because of

Nitrogenase needs which of the following ion for activation?

For the opening and closing of stomata which of the following ion is important?

Alcohol Dehydrogenase needs which of the following ion for activation?

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.