An approach to the determination of winter chill requirements for different Ribes cultivars

摘要: Winter chilling is critical for flowering and fruiting of many temperate fruits, with evidence that blackcurrant (Ribes nigrum L.) cropping has been adversely affected by warm winters. Accurate models chill accumulation in are required so breeding strategies can be formulated the generation new cultivars resilience to future climates. Existing have largely derived from statistical correlation; here we report derivation improved using controlled environment treatments. Hardwood cuttings a diverse set were exposed constant or varying temperatures effects on bud break after transfer warm, permissive evaluated. The impact different combinations temperature periods described terms their overall ‘Effectiveness’ (E). Clear genotypic differences found, excessive often inhibiting break. There was significant interaction between observed response period low exposure. A number explain interactions time exposure compared; most effective involved an optimal increasing accumulation. during complex, breaks substantially development cooler tending enhance burst. relevance these generic studies endodormancy discussed, together potential application phenotyping screens germplasm.