%0 Journal Article %A ELLIOTT, C. G. %A HENDRIE, MARGARET R. %A KNIGHTS, B. A. %T The Sterol Requirement of Phytophthora Cactorum %D 1966 %J Microbiology, %V 42 %N 3 %P 425-435 %@ 1465-2080 %R https://doi.org/10.1099/00221287-42-3-425 %I Microbiology Society, %X SUMMARY: Several sterols and related substances were tested for ability to promote sexual reproduction in Phytophthora cactorum. These compounds were classified as active (oospores formed), partially active (oogonia and antheridia formed, but no oospores), or inactive (no oogonia). Quantitative differences between active substances were noted in respect of the numbers of oospores produced and the time of their appearance. The most active substances tested were 29-isofucosterol and β-sitosterol. Loss of activity was associated with shortening of the side chain of the sterol molecule or change in its configuration, absence of a double bond in the B ring or of a hydroxyl group at position 3 on the A ring. %U https://www.microbiologyresearch.org/content/journal/micro/10.1099/00221287-42-3-425