Question

An intercropping system can be said beneficial, if it has LER:

• A. Equal to 1.0
• B. < 1.0
• C. >1.0
• D. Zero

Hint:

Recall that LER above 1.0 means the intercrop saves land compared with growing both crops as sole crops.

Answer 1

The Correct Option is C

Step 1: Understanding the Question:
The question asks at what value of Land Equivalent Ratio (LER) an intercropping system is considered to give a real advantage over growing the same crops as sole crops.

Step 2: Key Formula or Approach:
LER compares the land needed under intercropping with the land that would be needed to get the same total yield by growing each crop alone.
\[ LER = \frac{Y_{ab}}{Y_{aa}} + \frac{Y_{ba}}{Y_{bb}} \]
where \(Y_{ab}\) and \(Y_{ba}\) are the intercrop yields of crop A and crop B, and \(Y_{aa}\) and \(Y_{bb}\) are their respective sole crop yields.

Step 3: Detailed Explanation:
If LER equals 1.0, the intercrop uses exactly as much land as two separate sole crops would need to give the same yields, so there is no gain at all from intercropping.
If LER is less than 1.0, the intercrop system actually needs more combined land than sole cropping to match the same output, meaning intercropping performed worse than growing the crops separately.
If LER is zero, this would mean the intercrop produced nothing of value from either crop, clearly not a beneficial outcome.
If LER is greater than 1.0, the intercrop system produces the same total yield using less land than separate sole crops would need, which is the definition of a real land-use advantage from intercropping. For example, an LER of 1.3 means intercropping saves 30 percent of the land compared with growing both crops alone.

Step 4: Final Answer:
An intercropping system is beneficial when LER is greater than 1.0, option (3).