Peter: Because the leaves of mildly drought-stressed plants are tougher in texture than the leaves of abundantly watered plants, insects prefer to feed on the leaves of abundantly watered plants.
Conclusion (therefore)
To minimize crop damage, farmers should water crops only just enough to ensure that there is no substantial threat, from a lack of water, to either the growth or the yield of the crops.
Evidence
The leaves of mildly drought-stressed plants are tougher in texture than the leaves of abundantly watered plants.
Insects prefer to feed on the leaves of abundantly watered plants.
Evaluate
This argument fits the Recommendation pattern. Peter is suggesting a course of action (water plants minimally) to achieve a goal (minimize crop damage).
To assess this argument, we should consider whether following the recommendation would indeed lead to the intended outcome, with a net gain when compared to the current scenario of abundant watering.
The author thinks insects' preference for softer leaves means that mildly drought-stressed plants will experience less insect damage. The argument assumes that the benefit of reduced insect damage outweighs any negative effects of mild drought stress, so a strong point in favor would be evidence that supports minimizing insect damage as a priority.
Goal
Let's find an answer that highlights that the potential benefits of reduced insect feeding, thanks to watering crops less, outweigh the risks associated with slight drought stress.