Document Type

Dissertation - Open Access

Award Date

1966

Degree Name

Doctor of Philosophy (PhD)

Department / School

Agronomy

Abstract

Univalents were studied in the microsporocytes of a triploid sorghum plant which was derived from a selfed haploid. At metaphase I, the frequencies of univalent varied with cell maturity which was judged by anther development. The developmental stages of anthers were E, M, L, VL, and VVL for early, medium, late, very late, and very, very late respectively. Univalents averaged 2.3 per cell at the earliest (E) stage increased to 3.9 per cell at the latest (VVL) stage. A similar tendency was found from L to VVL at anaphase I and telophase I. Trivalents were also studied in cell populations used for study of univalents. The types of trivalent identified were linear, convergent and indifferent. No relationship was found between the occurrence of linear type trivalents and anther development. The frequency of convergent type trivalents was stable through five stages of anther development. However, indifferent type trivalents tended to decrease apparently in association with the increase in univalent. Averages of 2.3 linear type trivalents, 3.9 convergent type trivalents and 1.0 indifferent type trivalents per cell were found. (see more in text)

Library of Congress Subject Headings

Chromosomes
Sorghum

Format

application/pdf

Publisher

South Dakota State University

Share

COinS