Cytogenetics of corn (Zea mays), teosinte (Zea perennis) and BC1

Date

4-1993

Degree

Bachelor of Science in Biology

College

College of Arts and Sciences (CAS)

Adviser/Committee Chair

Dolores A. Ramirez

Abstract

he chromosome number of Zea mays was found to be 2n=20 Zea perennis was 2n=40, and BC1 was 2n=20-24. Zea mays. at diakinesis showed in high degree of normal pairing (II). A high percentage of normal behavior was observed in all of its meiotic stages which could explain its high pollen fertility (%). Zea perennis also showed a high degree of normal pairing (80%) at diakinesis. Despite the high degree of normal pairing, there was a low pollen fertility (38.25%) which was attributed to a genetic physiological factor of an unknown nature but not associated with meiotic abnormality. BC1 also had a relatively high degree of normal pairing and behavior which accounted for its high pollen fertility (77.09%). Pachytene analysis showed that Zea mays chromosomes have average relative lengths ranging from 0.0302-0.3096, Zea perennis with 0.0192-0.0876, and BC1 with 0.0425-0.1304. Presence of knobs was also observed. Comparing the chromosome characteristics of the BC1 with the parentals, it was concluded that there is a likelihood that the BC1 chromosomes are mostly maize-derived.

Language

English

Location

UPLB Main Library Special Collections Section (USCS)

Call Number

Thesis

Document Type

Thesis

This document is currently not available here.

Share

COinS