II. 28. Results of acridine dye treatment of Steptoe barley.
A. L. Hodgdon, P. Arenaz, and R. A. Nilan, Department of Agronomy and Soils, Washington State University, Pullman, Washington 99164 (U.S.A.)
In the fall of 1977 a series of acridine dye treatments, namely proflavin, acridine, acridine orange, and acriflavin, were performed on Steptoe barley for the purpose of inducing "waxy" mutants useful in an in situ mutagen monitoring system. The acridine dyes are known to induce frameshift mutations in plants and other organisms (Nasim and Brychcy, 1979). The mutagen treatments were replicated three times for each mutagen concentration used (Table 1) and were planted along with untreated controls in a randomized plot design. All treatments used 10% DMSO in an attempt to enhance mutagen uptake. The experiment was fall planted in Arizona.
In the spring of 1980 primary M1 spikes were harvested from mature plants, one per plant for chlorophyll deficient mutant analysis and "waxy" seed screening. Chlorophyll deficient mutants were analyzed in a greenhouse in the fall and winter of 1980 to evaluate the effectiveness of the mutagen treatments. The results are shown in Table 1. Although the mutagen concentrations were chosen due to apparent physiological effect on the seeds (seedling height and seed germination reduction), the treatments induced no significant increase in chlorophyll deficient mutants over the control level. In contrast to these results, it should be noted that an effective mutagen treatment of ethyl methanesulfonate (EMS) or sodium azide produces an M1 spike mutation frequency of 40-70% and an M2 mutant seedling frequency of 5-10%. The reason for the ineffectiveness of the treatments is not clear. Further work must be done to produce optimum treatment methods for the acridine dyes.
Reference:
Nasim, A. and T. Brychcy, 1979. Genetic effects of acridine compounds. Mutation Res. 65:261-288.
