Slovene has a word: vrtnica (wiktionary: en, sl) meaning "rose".
It resembles the known Proto-Indo-European *wr̥dʰos
“sweetbriar”, which gives Persian gul "rose, flower" and Old/Middle Iranian borrowings including Old Armenian vard "rose" and Ancient Greek ῥόδον (rhódon, "rose") (to name the most well-known reflexes).
(See, for example, the StarLing database entry *wordh-, *word-
or Wiktionary's etymology for rose.)
Can it be a Slavic reflex that survived from the Proto-Indo-European root? Or the historical sound laws would give a different appearance of the root in Slavic?
Note that the StarLing database entry *wordh-, *word-
or other etymological notes don't know any Slavic reflexes. To my knowledge, it is also not knwon in other Slavic languages, but Slovene.
If this could be a valid reflex of the Proto-Indo-European root according to the established historical sound laws, then it would be an interesting finding for Indo-European studies corroborating this reconstructed PIE root by the data from one more IE branch. Now the data from different branches is a bit scarce: taking into account that the Armenian form (and possibly the Greek one, too) is considered to be a borrowing, this reconstruction has a support from only two branches.
Appendix
The StarLing database entry *wordh-, *word-
:
Proto-IE: *wordh-, *word-
Meaning: sweetbrier
Avestan: { varǝδa- `rose' }
Other Iranian: NPers gul `Rose' (< *wrdho-, cf. Arm vard < Iran)
Old Greek: rhódo-n, äol. bródo-n n. `Rose'
Germanic: *wurɵ=, *wurd=
Proto-Germanic: *wurɵ=, *wurd=
Meaning: a bush
Norwegian: ol, dial. erre, orr (pl. errer), ordre
Swedish: dial. orr, arre, arder
Old English: { word `Dornstrauch' }
Russ. meaning: дерево (шиповник)
References: WP I 316