How to say "challenge" in Japanese?

Question

I often use sentences such as "the challenges of doing...", "the challenges xx have to face" for my research. I'm trying to translate that into Japanese, but I have trouble finding a word for "challenge". 課題 and 問題　have been suggested to me, but neither seems to fit perfectly. 課題 is probably more appropriate, but the meaning of "challenge" doesn't seem to be the main one.

Eg.

新規有機農家の課題は何ですか？ What are the challenges for new organic farmers?
有機農業を始める課題は。。。 The challenges of starting organic farming are...

Would these be okay in my case? Is there any better option?

Answer 1

課題 and 問題 are both fine. However you should avoid the following expressions because these are ambiguous and tend to mean something else:

• 有機農業を始める課題 task of starting organic farming
• 新規有機農家の問題 problems with new organic farmers (farmers themselves are troublesome)

My recommendations:

• 新規有機農家が抱える課題
• 有機農業を始めるにあたっての課題
• 有機農業を始めるに際しての問題/課題

挑戦 basically only refers to the action of trying hard to achieve something difficult. I doubt we need this word in this context.