Maize Genetics Cooperation Newsletter vol 81 2007
The study of
cytoplasmic effects on the expression of quantitative characters is important
to understanding cytoplasmic-nuclear interactions and their influence on
breeding and genetic programs. The
genotypes of six early-maturing maize inbreds T248, TC243, TC209, TB367, A654,
TC102, T291 were backcrossed eight times into ten cytoplasms other than their
own. Thus, each cytoplasmic source
of seed was assumed to have the same nuclear genotype. Five characters were studied over two
years and two locations.
Significant differences among the cytoplasms occurred for plant vigor,
date of tasseling and silking, stalk lodging resistance and kernel dry matter.
Differences in
grain yield among cytoplasms were not significant, or their expression was of
low magnitude, and probably due to interaction with environments. Differences that did exist were in the
direction expected on the basis of inbred performance. The results indicate that differences
in inbred performance were not necessarily an indication of cytoplasmic effects
in hybrid combination. Results
from these experiments provide further support for cytoplasmic effects on some
agronomic characters in maize.
They also emphasize that the environment can influence the performance
of cytoplasm from one year to another.
Table
1. Mean percent of stalk lodging
resistance at harvest for each of the ten cytoplasmic sources with six genotypes.
|
Pair
no. |
Inbred
genotype |
TC209 |
T291 |
T248 |
TC243 |
TB367 |
TC102 |
|
Cytoplasmic
source |
% |
% |
% |
% |
% |
% |
|
|
1. |
Own cytoplasm
|
61.1 |
32.6 |
68.6 |
68.0 |
66.1 |
42.6 |
|
2. |
T 291 |
61.0 |
x |
71.4 |
60.8 |
70.2 |
53.8** |
|
3. |
T 248 |
61.3 |
49.9** |
x |
68.8 |
69.6 |
59.1*** |
|
4. |
TC 243 |
55.0 |
30.7 |
66.4 |
x |
72.1* |
58.9*** |
|
5. |
A 654 |
61.3 |
56.7*** |
70.9 |
60.2 |
71.5 |
59.0*** |
|
6. |
TC 221 |
61.5 |
35.5 |
66.8 |
63.5 |
63.3 |
55.8** |
|
7. |
TC 102 |
55.4 |
41.4 |
67.1 |
69.9 |
70.5 |
x |
|
8. |
TC 209 |
x |
56.6*** |
69.0 |
65.5 |
71.4 |
44.2 |
|
9. |
K 1080 |
58.3 |
40.2 |
68.3 |
62.8 |
62.5 |
48.3 |
|
10. |
TC 316 |
60.2 |
30.7 |
58.800 |
64.7 |
74.9** |
40.4 |
|
|
LSD 5% |
9.0 |
9.9 |
7.0 |
10.7 |
5.8 |
7.9 |
|
|
1% |
12.0 |
13.4 |
9.4 |
14.6 |
7.8 |
10.7 |
|
|
0.1% |
15.8 |
17.7 |
12.4 |
19.5 |
10.3 |
14.1 |
Please Note: Notes submitted to the Maize Genetics Cooperation
Newsletter may be cited only with consent of authors.