Masters Theses

Date of Award

3-1987

Degree Type

Thesis

Degree Name

Master of Science

Major

Plant, Soil and Environmental Sciences

Major Professor

B. V. Conger

Committee Members

V. H. Reich, S. E. Schlarbaum

Abstract

The primary objective of this study was to determine if the ability of an orchardgrass (Dactylis glomerata L.) genotype to produce somatic embryos in vitro culture could be sexually transmitted to genotypes not possessing this ability. Reciprocal crosses were performed between embryogenic and nonembryogenic genotypes. Seeds from crosses were germinated and plants maintained in a greenhouse. Leaf sections of F1 plants (27 crosses and 4 selfs) were cultured on Schenk and Hildebrandt (SH) medium amended with 30 μM 3,6-dichloro- o-anisic acid (dicamba) and evaluated for embryogenic response. There were no significant differences between F1 plants in which females were the embryogenic parents and those in which males were the embryogenic parents for the production (mean number) of somatic embryos and the ability of these somatic embryos to produce viable shoots. Five crosses individually compared with their reciprocals were not significantly different for the production (mean number) of somatic embryos and their ability to produce shoots. Two embryogenic parents compared to their F1 progeny were not significantly different for the production of somatic embryos. However, one parent was significantly different from its F1 progeny for the total shoots produced. The ratios of embryogenic to nonembryogenic F1 progeny and of embryogenic females to embryogenic males were 1:1. Secondary goals were to determine the influence of sucrose on the germination of somatic embryos and the development of meristematic tissue in somatic embryos. Seventy percent of the somatic embryos that were cultured on SH with 3% sucrose produced shoots whereas, only 27% of those cultured on SH without sucrose produced shoots. Shoot and/or root apices from somatic embryos of F1 derived leaf cultures were observed from histological sections of somatic embryos, but there was insufficient data to make any conclusions. Transmission of somatic embryogenesis was demonstrated to be under control of nuclear gene(s) due to lack of significant effects for reciprocal crosses. The embryogenic trait was effectively incorporated into nonembryogenic genotypes via sexual hybridizations. This research provides preliminary information that will be useful for further understanding somatic embryogenesis in orchardgrass.

Download
Files over 3MB may be slow to open. For best results, right-click and select "save as..."

Share

COinS