Dorothy Mary Cayley

Dorothy Mary Cayley (1874–1955) was a Sri Lankan mycologist who discovered in 1927 that "Tulip breaking" is due to a virus.

Early life and education Cayley was born in Sri Lanka in 1874, where her father, Sir Richard Cayley, was the 14th Chief Justice. Cayley came to England from Sri Lanka when she was seven and attended Stamford High School. She went to London University before studying horticulture at University College, Reading. Cayley was especially interested in plant disease and soils and entered the board of education's examination in horticulture which gained her first-class honours and a medal while in Reading. She also took a first class in the Royal Horticultural Society Examination and was appointed as the superintendent of the gardens that belonged to the Botanical Department at Reading.

Dorothy was also a talented artist. She drew the fungus she was examining and took her paint on holidays. Through bulb-grafting experiments, she found that "Tulip Breaking" could be transferred from one plant to another, rather than being genetic in nature. She concluded that the infectious agent was a virus as the filtrate of an infected bulb did not cause "breaking", and that the virus was probably spread by aphids. Cayley described her findings in two articles published in 1928 and 1932.

Publications Cayley's publications include:

Dorothy M. Cayley (1923) Fungi associated with 'Die Back' in stone fruit trees. I. Annals of Applied Biology 10 (2) pp. 253–275. Dorothy M. Cayley (1923) The phenomenon of mutual aversion between mono-spore mycelia of the same fungus (Diaporthe perniciosa, Marchal). With a discussion of sex-heterothallism in fungi. Journal of Genetics 13 (3) pp. 353–370. Dorothy M. Cayley (1928) 'Breaking' in tulips. Annals of Applied Biology 15 pp. 529–539.