02102naa a2200241 a 450000100080000000500110000800800410001910000200006024501530008026000090023352013560024265000120159865000100161065000370162065000120165765000350166965000090170465300090171365300290172265300370175170000170178877300550180516257772004-05-14       2003    bl ---       0--  u    #d1 aSOUZA, F. A. de  aMycelium development and architecture, and spore production of Scutellospora reticulata in monoxenic culture with Ri T-DNA transformed carrot roots.  c2003  aMycelium development and architecture and spore production were studied in Scutellospora reticulata from single-spore isolates grown with Ri T- DNA transformed carrot root-organ culture in monoxenic system. Culture establishment, anastomosis occurrence and auxiliary cell development also were examined. Seventy percent of the pregerminated disinfected spores colonized the transformed carrot roots. After 8 mo, the average spore production was 56 (24-130) per 30 cm3 of medium. Of the spores produced, 75% germinated and produced new generations in monoxenic culture. The mycelium net- work was formed by thick light-brown hyphae, which exhibit two major architecture patterns related to either root colonization or resource exploitation, and lower-order hyphae, bearing auxiliary cells, branched absorbing structures (BAS) , hyphal swellings (HS) and forming anastomoses. BAS were formed abundantly in extramatrical mycelium and frequently had HS resembling vesicles, a feature not previously re- ported in the Gigasporaceae, to the best of our knowledge. Few anastomosis were observed within the mycelium and most often corresponded to a healing mechanism that form hypha bridges to reconnect broken hyphae or overcoming obstructed areas within a hypha. Numerous auxiliary cells were produced during culture development and their role was inferred.  acarrots  aroots  avesicular arbuscular mycorrhizae  aCenoura  aMicorriza Vesicular Arbuscular  aRaiz  aRoot  aScutellospora reticulata  aVesicular arbuscular mycorrhizal1 aDECLERCK, S.  tMycologia, Bronxgv. 95, n. 6, p. 1004-1012, 2003.