title: Linear energy transfer dependence of the effects of carbon ion beams on adventitious shoot regeneration from in vitro leaf explants of Saintpaulia ionahta.
abstract: OBJECTIVE
  To determine the effects of carbon ion beams with five different linear energy transfer (LET) values on adventitious shoots from in vitro leaf explants of Saintpaulia ionahta Mauve cultivar with regard to tissue increase, shoots differentiation and morphology changes in the shoots.
  
  
  METHODS
  In vitro leaf explant samples were irradiated with carbon ion beams with LET values in the range of 31 approximately 151 keV/microm or 8 MeV of X-rays (LET = 0.2 keV/microm) at different doses. Fresh weight increase, surviving fraction and percentage of the explants with regenerated malformed shoots in all the irradiated leaf explants were statistically analysed.
  
  
  RESULTS
  The fresh weight increase (FWI) and surviving fraction (SF) decreased dramatically with increasing LET at the same doses. In addition, malformed shoots, including curliness, carnification, nicks and chlorophyll deficiency, occurred in both carbon ion beam and X-ray irradiations. The induction frequency with the former, however, was far more than that with the X-rays.
  
  
  CONCLUSIONS
  This work demonstrated the LET dependence of the relative biological effectiveness (RBE) of tissue culture of Saintpaulia ionahta according to 50% FWI and 50% SF. After irradiating leaf explants with 5 Gy of a 221 MeV carbon ion beam having a LET value of 96 keV/microm throughout the sample, a chlorophyll-deficient (CD) mutant, which could transmit the character of chlorophyll deficiency to its progeny through three continuous tissue culture cycles, and plantlets with other malformations were obtained.
authors.affiliation: Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou, PR China. libinzhou@impcas.ac.cn
authors.forename: Libin
authors.initials: L
authors.lastname: Zhou
authors.forename: Wenjian
authors.initials: W
authors.lastname: Li
authors.forename: Lixia
authors.initials: L
authors.lastname: Yu
authors.forename: Ping
authors.initials: P
authors.lastname: Li
authors.forename: Qiang
authors.initials: Q
authors.lastname: Li
authors.forename: Shuang
authors.initials: S
authors.lastname: Ma
authors.forename: Xicun
authors.initials: X
authors.lastname: Dong
authors.forename: Guangming
authors.initials: G
authors.lastname: Zhou
authors.forename: Corinne
authors.initials: C
authors.lastname: Leloup
mesh_terms: D002250:Carbon Radioisotopes; D002454:Cell Differentiation / Q000528:radiation effects; D049109:Cell Proliferation / Q000528:radiation effects; D002478:Cells, Cultured; D004307:Dose-Response Relationship, Radiation; D020450:Heavy Ions; D018499:Linear Energy Transfer / Q000502:physiology* / Q000528:radiation effects; D031566:Magnolia / Q000502:physiology* / Q000528:radiation effects; D018515:Plant Leaves / Q000502:physiology* / Q000528:radiation effects; D018547:Plant Stems / Q000502:physiology* / Q000528:radiation effects*; D011829:Radiation Dosage; D012038:Regeneration / Q000528:radiation effects*
chemical_list: D002250:Carbon Radioisotopes