The most common and most likely answer to this crossword clue is the 5 letter word FUNGI
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More clues leading to the result FUNGI
- A great time - one eating good mushrooms
- Growths initially found upsetting New Guinea islander
- Moulds are amusing — man impressed
- Tomfoolery with soldier’s mouldy things
- Delightful chap on the radio provides penicillin, etc
- With joy, pig returns unopened truffles, perhaps
- Parasols possibly amusing Joe
- Animal tucks in, if turning up truffles, say
- Joy to have pigs’ heart served up on mushrooms
- Fuming, missing medium shaped moulds?
Buddy explains!

The straight part
We know that "rising agents" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case rising agents = fungi.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does FUNGI mean?
FUNGI noun- Any member of the kingdom Fungi; a eukaryotic organism typically having chitin cell walls but no chlorophyll or plastids. Fungi may be unicellular or multicellular.
- A spongy, abnormal excrescence, such as excessive granulation tissue formed in a wound.
- A style of folk and popular music from the Virgin Islands, traditionally performed by bands consisting of ukulele, banjo, guitar and washboard with various percussion instruments on rhythm.
- A cornmeal dish eaten in the Caribbean, usually made with okra and served with salt fish, shellfish or chicken; variant recipes are also known as cou-cou (coucou) or coo-coo (coocoo).