Interaction of environment and ABA and GA treatments on the maize anther culture response

Treatments designed to influence abscisic acid (ABA) or gibberellin (GA) co ncentrations were applied to developing tassels of maize (Zen mays L.) plan ts in different environments or to anthers in culture to determine the effe ct on formation of embryo-like structures (ELS). Production of ELS was sign ificantly affected in certain environments when ABA, GA(3), ancymidol, or f luridone solutions were pipetted into whorls of field-grown plants approxim ately 3 days before tassel harvest. In 1996 anthers from 10 muM ancymidol-t reated plants were most responsive, producing 35 ELS/100 anthers and 50 muM GA(3)-treated plants were least responsive, producing 12 ELS/100 anthers. In 1997 under hotter, drier conditions, anthers from 50 muM GA(3)-treated p lants were most responsive, producing 20 ELS/100 anthers and those from 50 muM ABA-treated plants were least responsive, producing 2.4 ELS/100 anthers . Anthers from growth chamber plants were significantly more responsive whe n grown in a 16-h than a 12-h photoperiod. With the 16-h photoperiod the re sponse was significantly greater with a 250 muM ABA whorl treatment. With t he 12-h photoperiod there was no significant effect from whorl treatments. Modification of the culture medium with added ABA, GA(3), ancymidol, or flu ridone was generally ineffective, except in 1997 when the response was sign ificantly higher with 1 muM ABA added to the culture medium. The results su ggest that the maize anther culture response may be influenced by environme ntal conditions that interact with ABA and GA treatments to donor plants du ring tassel development.