Ethylene inhibitors enhanced de novo shoot regeneration from cotyledons of Brassica campestris ssp. chinensis (Chinese cabbage) in vitro

Abstract

A tissue culture system for obtaining high frequency shoot regeneration of Brassica campestris ssp. chinensis cv. Speedy and 2B-21-64 was optimized via judicious selection of explants and manipulation of culture medium with respect to hormonal combination and addition of AgNO3, Ag2SO4, aminoethyoxyvinylglycine (AVG), aminooxyacetic acid (AOA) or 2,4-dinitrophenol (DNP). Three-day-old cotyledons of both cultivars grown on Murashige and Skoog's medium supplemented with 4.4-17.6 μM benzyladenine and 2.7-5.4 μM naphthaleneacetic acid (NAA) in the presence of 7.5-60 μM AgNO3 or Ag2SO4 or medium containing 8.8 μM BA, 5.4 μM NAA and 0.1-10 μM AVG formed shoots at 70-85% frequency after 3-4 weeks, whereas explants grown in the absence of Ag+ or AVG or in the presence of AOA or DNP were poorly regenerative (20-30%). Shoot tips originating from regenerants and seedlings rooted equally well in hormone-free medium or medium containing 0.05-5 μM indolebutyric acid. All rooted shoots were successfully acclimatized. The acclimatized plants were phenotypically indistinguishable from those derived from seeds. © 1989.