Characterisation of the interaction between cryptochromes and phytochromes in blue light‐induced coiling and prehaustoria development of dodder (Cuscuta campestris) seedlings

Summary Previous studies demonstrated that blue, near far‐red and a mixture of red and far‐red light stimulate, while red light inhibits coiling and prehaustoria development in young excised de‐etiolated dodder seedlings. In this study, evidence was obtained for the involvement of cryptochromes in the mediation of coiling and prehaustoria development in response to blue light. The results indicated that coiling and prehaustoria are affected by the addition of red or far‐red light and therefore are dependent on the state of phytochromes. Results also suggest the occurrence of a synergistic interaction between phytochromes (Pr) and cryptochromes and an antagonistic interaction between phytochromes (Pfr) and cryptochromes in mediating coiling and prehaustoria development. Gabaculine significantly reduced coiling and prehaustoria development under far‐red or a mixture of red and far‐red light but not under blue or a mixture of blue and far‐red light, indicating that cryptochromes are involved in blue‐induced coiling and prehaustoria development.