Cucurbit Genetics Cooperative Report 3:63 (article 34) 1980
Karyo-Morphology of Cucumis callosus (Rottl.)
Cogn.
V. A. Parthasarathy and C. N. Sambandam
ICAR Research Complex for NEH
Region, Shillong-793 003, India (first author); Faculty
of Agriculture, Annamalai University TN-608 101, India (second author)
Detailed karyo-morphological studies of Cucumis callosus
were made from root tip squashes following the procedure
of Parthasarathy and Sampathkumar (1). Observations made
on several metaphase plates revealed the presence of 24
chromosomes in the somatic cells. The length of 1.67 µ.
The karyotype is symmetrical in view of the preponderance
of median centromeres. The karyotype is presented in the
following table.
Table 1. Length and arm ratio of the chromosomes of Cucumis
callosus.
|
Length of chromosomes (µ) |
|
|
|
No. of chromosomes for each type |
long arm |
short arm |
total |
L/S ratio |
Relative length |
Position of centromere and secondary constriction |
4 |
1.00 |
1.00 |
2.00 |
1.00 |
19.95 |
median and satellite |
6 |
1.00 |
1.00 |
2.00 |
1.00 |
29.93 |
median |
2 |
1.00 |
0.75 |
1.75 |
1.33 |
8.73 |
sub-median |
4 |
1.00 |
0.50 |
1.50 |
2.00 |
14.96 |
sub-median |
2 |
0.75 |
0.75 |
1.50 |
1.00 |
7.48 |
median |
2 |
1.25 |
0.25 |
1.50 |
5.00 |
7.48 |
sub-median |
2 |
0.65 |
0.65 |
1.30 |
1.00 |
6.48 |
median |
2 |
0.75 |
0.25 |
1.00 |
3.00 |
4.99 |
sub-median |
24 |
|
|
|
|
|
|
Literature Cited
- Parthasarathy, V. A. and R. Sampathkumar. 1979. Karyo-morphological
studies on Cucumis sp. cv. Vellari. Curr.
Res. 8:175-176.
