Paper · 1976 · Crop Science

Cytological Characteristics and Nuclear DNA Bouyant Densities of Corn, Teosinte, Tripsacum, and Corn‐tripsacum Hybrids1

C. S. Levings; D. H. Timothy; W. W. L. Hu

11
claims
15
verbatim quotes
9
citations
2
research areas
—
Not open access

Abstract

This study assesses the variability in buoyant density of nuclear DNA (nDNA) of corn and its relatives and the effect of several cytological phenomena on the demity of nDNA. The nDNAs of four Tripsacum L. spp., corn ( Zea mays L.), annual teosinte ( Z. mexieana [Schrad.] Kuntze), perennial teosinte ( Z. perennis [Hitchc.] Reeves and Manglesdorf), and corn‐tripsacum hybrids were characterized for buoyant densities. Corn and perennial teosinte nDNA densities were similar but were significantly greater than those of tripsacum and annual teosinte. The latter two did not differ in densities. The corntripsacum hybrid densities resembled those of the higher parent. However small significant differences in parental base composition did not preclude hybridization. In all cases, and typical of grasses, nDNAs were resolved as single bands without satellites and with relatively high guanine and cytosine contents. Chromosome numbers of T. andersonii Gray, in ed., Guatemala grass, are reported for the first time (2n = 64). Chromosomal knob numbers of 12 Tripsocum accessions ranged from 0 to 40. One Tripsacum accession had 3 to 4 B chromosomes. The presence of chromosomal knobs and B chromosomes in tripsacums had no effect on the banding pattern and buoyant density of the nDNAs as determined by neutral CsCI analytical eentrifugation. Although similarities and significant differences in buoyant densities of nDNA were found among corn and its relatives, the value of these results for establishing genetic relationships is not clear.

Abstract from the paper’s OpenAlex record, shown for indexing and research. Copyright remains with the authors or the publisher. Read at the source ↗

The text the model read, with the source record’s inline markup (italics, sub- and superscripts) rendered and its character entities decoded; quote offsets refer to the raw text.

Claims 11

Observationobservedoriginal resultno effectmeasured

Claim · model-written summary

Corn and perennial teosinte nDNA densities were similar.

Taxon
Zea maysZea mayse0
Outcome
nDNA densitiese1
Direction
similare1

Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Zea mays
Zea mays · TaxonAkwugo · CC BY-SA 4.0 · Wikimedia Commons ↗

Verbatim

e0

“corn ( Zea mays L.)”

✓ located verbatim in the source · abstract, characters 211–230 · show in text ↑
e1

“Corn and perennial teosinte nDNA densities were similar but were significantly greater than those of tripsacum and annual teosinte”

✓ located verbatim in the source · abstract, characters 418–548 · show in text ↑
Observationobservedoriginal resultsignificant (as stated)measured

Claim · model-written summary

Corn and perennial teosinte nDNA densities were significantly greater than those of tripsacum and annual teosinte.

Taxon
Zea maysZea mayse0
Outcome
nDNA densitiese1
Direction
significantly greatere1
Comparator
tripsacum and annual teosintee1

Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Zea mays
Zea mays · TaxonAkwugo · CC BY-SA 4.0 · Wikimedia Commons ↗

Verbatim

e0

“corn ( Zea mays L.)”

✓ located verbatim in the source · abstract, characters 211–230 · show in text ↑
e1

“Corn and perennial teosinte nDNA densities were similar but were significantly greater than those of tripsacum and annual teosinte”

✓ located verbatim in the source · abstract, characters 418–548 · show in text ↑
Observationobservedoriginal resultno effectmeasured

Claim · model-written summary

Tripsacum and annual teosinte did not differ in nDNA densities.

Taxon
tripsacumTripsacume1
Outcome
densitiese2
Direction
did not differe2

Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Tripsacum
Tripsacum · Taxon · picture of the genus (one of its species)US Department of Agriculture · Public domain · Wikimedia Commons ↗

Verbatim

e1

“Corn and perennial teosinte nDNA densities were similar but were significantly greater than those of tripsacum and annual teosinte”

✓ located verbatim in the source · abstract, characters 418–548 · show in text ↑
e2

“The latter two did not differ in densities”

✓ located verbatim in the source · abstract, characters 550–592 · show in text ↑
Observationobservedoriginal resultmeasured

Claim · model-written summary

Corn-tripsacum hybrid nDNA densities resembled those of the higher parent.

Taxon
corntripsacum hybride3
Outcome
densitiese3
Qualifier
resembled those of the higher parente3

Verbatim

e3

“The corntripsacum hybrid densities resembled those of the higher parent”

✓ located verbatim in the source · abstract, characters 594–665 · show in text ↑
Observationobservedoriginal resultsignificant (as stated)measured

Claim · model-written summary

Small significant differences in parental base composition did not preclude corn-tripsacum hybridization.

Taxon
Zea maysZea mayse0
Outcome
parental base compositione4
Qualifier
did not preclude hybridizatione4

Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Zea mays
Zea mays · TaxonAkwugo · CC BY-SA 4.0 · Wikimedia Commons ↗

Verbatim

e0

“corn ( Zea mays L.)”

✓ located verbatim in the source · abstract, characters 211–230 · show in text ↑
e4

“small significant differences in parental base composition did not preclude hybridization”

✓ located verbatim in the source · abstract, characters 675–764 · show in text ↑
Observationobservedoriginal resultmeasured

Claim · model-written summary

In grasses nDNAs were resolved as single bands without satellites.

Taxon
grassese5
Outcome
nDNAs were resolved as single bandse5
Qualifier
without satellitese5

Verbatim

e5

“In all cases, and typical of grasses, nDNAs were resolved as single bands without satellites and with relatively high guanine and cytosine contents”

✓ located verbatim in the source · abstract, characters 766–913 · show in text ↑
Observationobservedoriginal resultmeasured

Claim · model-written summary

In grasses nDNAs had relatively high guanine and cytosine contents.

Taxon
grassese5
Outcome
guanine and cytosine contentse5
Direction
relatively highe5

Verbatim

e5

“In all cases, and typical of grasses, nDNAs were resolved as single bands without satellites and with relatively high guanine and cytosine contents”

✓ located verbatim in the source · abstract, characters 766–913 · show in text ↑
Observationobservedoriginal resultmeasured

Claim · model-written summary

Chromosome number of T. andersonii is 2n = 64, reported for the first time.

Taxon
T. andersoniiTripsacum andersoniie6
Outcome
Chromosome numberse6
Value
2n = 64e6

Verbatim

e6

“Chromosome numbers of T. andersonii Gray, in ed., Guatemala grass, are reported for the first time (2n = 64)”

✓ located verbatim in the source · abstract, characters 915–1023 · show in text ↑
Observationobservedoriginal resultmeasured

Claim · model-written summary

Chromosomal knob numbers of Tripsacum accessions ranged from 0 to 40.

Taxon
Tripsocume7
Outcome
Chromosomal knob numberse7
Value
0 to 40e7

Verbatim

e7

“Chromosomal knob numbers of 12 Tripsocum accessions ranged from 0 to 40”

✓ located verbatim in the source · abstract, characters 1025–1096 · show in text ↑
Observationobservedoriginal resultmeasured

Claim · model-written summary

One Tripsacum accession had 3 to 4 B chromosomes.

Taxon
TripsacumTripsacume1
Outcome
B chromosomese1
Value
3 to 4e1

Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Tripsacum
Tripsacum · Taxon · picture of the genus (one of its species)US Department of Agriculture · Public domain · Wikimedia Commons ↗

Verbatim

e1

“One Tripsacum accession had 3 to 4 B chromosomes”

✓ located verbatim in the source · abstract, characters 1098–1146 · show in text ↑
Associationobservedoriginal resultno effectmeasured

Claim · model-written summary

Chromosomal knobs and B chromosomes had no effect on the banding pattern and buoyant density of nDNA in tripsacums.

Taxon
tripsacumsTripsacume1
Treatment
presence of chromosomal knobs and B chromosomese1
Outcome
banding pattern and buoyant density of the nDNAse1
Direction
had no effecte1

Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Tripsacum
Tripsacum · Taxon · picture of the genus (one of its species)US Department of Agriculture · Public domain · Wikimedia Commons ↗

Verbatim

e1

“The presence of chromosomal knobs and B chromosomes in tripsacums had no effect on the banding pattern and buoyant density of the nDNAs”

✓ located verbatim in the source · abstract, characters 1148–1283 · show in text ↑