A type of inter-cropping system in which yields of both crops, grown together are found to be higher than the yield of their pure crops on a unit area basis is known as – (RJ AARO Agronomy

✅Explanation:
Synergetic cropping is a type of intercropping where the combined yield of two crops grown together is significantly higher than the sum of the yields of each crop grown separately. This synergistic effect is due to various factors like complementary resource use, improved microclimate, and reduced pest and disease pressure.

📌 Other Options Explanations:
-Option A: Parallel cropping is a type of intercropping where two crops are sown simultaneously in alternate rows.
-Option B: Companion cropping involves growing two or more crops together in the same field, but they may not necessarily have a synergistic effect.
-Option C: Multi-storeyed cropping is a type of intercropping where crops of different heights are grown together in layers to maximize the use of sunlight and space.

🔴Additional information::
Synergetic cropping: The yields of both crops are higher than their pure crop on a unit area basis is called synergetic cropping. e.g., Sugarcane + Potato
i) Additive Series: In this system, one crop is the main crop or base crop, and another crop is the intercrop.
-Intercrop is introduced into the base crop by adjusting or changing crop geometry.
-Plant population of the main crop is kept the same as that recommended for a pure stand by reducing row spacing.
-Intercrop is sown in the reduced space.
-The objective of the system is to get additional income and to cover risk.
-LER (Land Equivalent Ratio) is more than 1.
-Additive series is more efficient than the replacement series.
ii) Replacement Series: Both crops are component crops. The plant population of both crops is less than their recommended population in a pure stand. LER is less than 1.  
-Replacement series is less efficient than the Additive series.