Question

Match LIST I with LIST II
\[ \begin{array}{|l|l|} \hline \textbf{LIST I (Crop)} & \textbf{LIST II (Ideal IW/CPE for irrigation)} \\ \hline A. \ \text{Sorghum} & I. \ 0.8 \\ B. \ \text{Maize} & II. \ 0.9 \\ C. \ \text{Cotton} & III. \ 0.6 \\ D. \ \text{Barley} & IV. \ 0.75 \\ \hline \end{array} \]
Choose the correct answer from the options given below:

• A. A-I, B-II, C-III, D-IV
• B. A-II, B-I, C-IV, D-III
• C. A-III, B-I, C-II, D-IV
• D. A-II, B-I, C-III, D-IV

Hint:

The IW/CPE ratio reflects a crop's sensitivity to water stress. High-water-use, sensitive crops (like maize) have high ratios (\(\approx\)1.0), while drought-tolerant crops (like cotton) have lower ratios (\textless0.8).

Answer 1

The Correct Option is A

Step 1: Comprehend the IW/CPE ratio method for irrigation scheduling.
IW/CPE (Irrigation Water / Cumulative Pan Evaporation) is a ratio used to determine irrigation timing. Irrigation is initiated when the cumulative pan evaporation reaches a specific threshold relative to the applied irrigation water depth. A lower IW/CPE ratio (e.g., 0.6) indicates greater crop drought tolerance, requiring less frequent watering. Conversely, a higher ratio (e.g., 0.9) signifies higher water demand and more frequent irrigation needs.
Step 2: Associate each crop with its characteristic IW/CPE ratio.
- C. Cotton: Possessing a deep root system and being relatively drought-tolerant, cotton exhibits the lowest IW/CPE ratio among the given options. Associate C with III. 0.6.
- D. Barley: As a winter cereal with moderate water requirements, barley is matched with IV. 0.75.
- A. Sorghum: A summer cereal that is more drought-tolerant than maize but requires more water than barley or cotton. Match A with I. 0.8.
- B. Maize: This summer cereal has high water requirements and is highly susceptible to water stress, thus having the highest IW/CPE ratio. Match B with II. 0.9.
Step 3: Consolidate the accurate pairings.
The resulting correct pairings are: A-I, B-II, C-III, D-IV. This corresponds to option (A).