Which of the following is incorrect statement for hydroponics

Options

A. role of individual elements has been largely determined
B. usually, a small volume of nutrient solution is required for hydroponic culture
C. concentration of nutrients is adjusted frequently to prevent changes in nutrient concentration and pH of the medium.
D. Vigorous bubbling of the air through the medium is also routinely done to provide sufficient oxygen

Explanation

To determine which statement about hydroponics is incorrect, we can follow these steps:

### Step 1: Understand Hydroponics
Hydroponics is defined as the soilless growth of plants in a nutrient solution. This means that plants are grown without soil, using a water-based solution that contains all the essential nutrients they need.

**Hint:** Remember that hydroponics relies on nutrient solutions instead of soil for plant growth.

### Step 2: Analyze Each Statement
Now, let's evaluate the statements provided in the question:

1. **Role of individual elements has been largely determined.**
- This statement is correct. In hydroponics, since plants are grown in nutrient solutions, the role of each nutrient can be studied and understood clearly.

2. **Usually a small volume of nutrient solution is required for hydroponic culture.**
- This statement is incorrect. Hydroponics typically requires a larger volume of nutrient solution to support plant growth, not a small volume.

3. **The concentration of nutrients is adjusted frequently to prevent changes in nutrient concentration and pH of the medium.**
- This statement is correct. Regular adjustments are necessary to maintain optimal nutrient levels and pH for plant health.

4. **Vigorous bubbling of air through the medium is routinely done to provide sufficient oxygen.**
- This statement is also correct. Oxygen is essential for plant roots, and bubbling air through the nutrient solution helps ensure that the roots receive enough oxygen.

### Step 3: Identify the Incorrect Statement
After analyzing the statements, we find that the second statement is incorrect because it suggests that a small volume of nutrient solution is sufficient for hydroponics, which is not true.

**Final Answer:** The incorrect statement for hydroponics is the second statement: "Usually a small volume of nutrient solution is required for hydroponic culture."