Variability for components of yield induced in soybeans by seed treatment with gamma radiation, fission neutrons, and ethylmethane sulfonate

Author

Larry Wayne Skinner

Date of Award

12-1975

Degree Type

Thesis

Degree Name

Master of Science

Major

Plant, Soil and Environmental Sciences

Major Professor

B. V. Conger

Committee Members

L. N. Skold, V. H. Reich

Abstract

The primary objective of this study was to evaluate the variability for five individual yield components in soybean (Glycine max (L.) Merr.) induced by seed treatment with fission neutrons, ethylmethane sulfonate, and gamma radiation. Nine M₃ and nine M₄populations, resulting from three doses of each mutagen, were compared with a control for pods per plant, number of seed per plant, number of seed per pod, weight per 100 seed, and total seed weight per plant. Variability induced by the three mutagens was determined by the following four methods: analysis of variance of treatment means, ranges in population means, intraclass correlations of family means, and frequency distributions of family means. The latter was considered to be the most reliable measure of induced variability. An analysis of variance of treatment means revealed differences between the various mutagen treatments, but in most cases, the control population means were equal to or higher than any of the mutagen treatments. In nearly all cases, ranges were increased by mutagen treatment for all yield components when compared with the control, especially in the M₃ population. Although the values obtained for the intraclass correlations were biased upward, differences were observed for certain treatments. The most heritable yield component appeared to be weight per 100 seed while the other yield components showed variable heritability values from treatment to treatment. The M₄ population was more variable than the M₃ population in intraclass correlation values although treatment means were less variable. Differences were also noted for certain treatments when a comparison of frequency distributions was made. In the M₃ population, the 0.050 M EMS treatment was significantly different from the control for all three yield components, and the 0.025 M EMS and 1.5 krads N_f treatments were significantly different for two components each. In the M₄ population, the 0.025 M EMS treatments differed from the control for two yield components. All N_f treatments and the 20 and 30 krads gamma radiation treatments differed from the control for weight per 100 seed. EMS was the most effective mutagen for increasing variability. Neutrons were the second most effective mutagen for increasing variability and gamma radiation the least effective.

Recommended Citation

Skinner, Larry Wayne, "Variability for components of yield induced in soybeans by seed treatment with gamma radiation, fission neutrons, and ethylmethane sulfonate. " Master's Thesis, University of Tennessee, 1975.
https://trace.tennessee.edu/utk_gradthes/8093