ABSTRACT
Rickettsia-like bacteria associated with plum leaf scald and phony peach diseases were isolated from diseased but not from healthy tissues and cultured on charcoal-yeast extract medium (BCYE) buffered with ACES (2-[(2-amino-2-oxoethyl) amino]-ethanesulfonic acid). Optimum conditions for isolation and growth on BCYE medium were pH 6.5 to 6.9 at 20 and 25 degrees C under normal atmosphere. Growth of primary colonies and first-passage subcultures was restricted, and colonies reached a maximum diameter of 0.6 mm in 60 days. After 12 passages, subcultures reached maximum growth in 21 days. The rickettsia-like bacteria from BCYE cultures were gram negative, serologically the same as those present in diseased peach and plum, and composed of rod-shaped cells measuring 0.35 by 5 mum (average diameter and maximum length) in a matrix of filamentous strands of similar width but of variable length.
ABSTRACT
Spiroplasmas were cultured from nonsurface-sterilized flowers of magnolia tree (Magnolia grandiflora L.) and tulip tree (Liriodendron tulipfera L.) in Alameda, Solano, and Yolo counties in California. Spiroplasmas were also isolated from honey bees (Apis mellifera L.) collected in the vicinity of Davis and Berkeley, CA. Most of the isolates grew relatively slowly at 31 or 37 degrees C reaching maximum population at 31 degrees C in 8-10 days. The flower isolates were serologically indistinguishable by deformation and growth inhibition tests of spiroplasma strain AS-576 from honey bee from Maryland. Isolates from honey bees were serologically closely related to spiroplasma strain SE-3 from tulip tree flower from Connecticut.
