Full explanation
Platform choice gates hybrid selection, seed rate, and herbicide programme. Clearfield (CL, HRAC 2): post-emergence imazamox (Euro-Lightning, Pulsar Flex) at BBCH 10–18, broadleaf spectrum + some grasses; Clearfield Plus (CLP): broader spectrum + weaker soil persistence = less carry-over for the next crop; ExpressSun (ES, HRAC 2): tribenuron-methyl (Express 50 SG, Granstar), broadleaf-only; LibertyLink (LL, HRAC 10): glufosinate (Basta, Liberty) — still limited UA registration. 2024 Ukrainian share: Clearfield+CLP ≈ 55% of area, ExpressSun ≈ 22%, Conventional ≈ 20%, LibertyLink ≈ 3% [VERIFY]. Trade-offs: CL/CLP more expensive seed (+8–15%) + herbicide premium; ES cheaper but doesn't control broomrape — relies on the Pl gene; LL needs special resistance-testing equipment. Source: seed-kb.ts `ht_platform` enum + the sunflower-ht-platform-picker calculator.