Cucurbit Genetics Cooperative Report 14:10-11 (article 4) 1991
P. Milotay, L. Kecskemeti and I. Cserni
Vegetable Crops Research Institute, 6000 Kecskemet, Hungary
Seed yield in the field for new breeding lines is generally estimated by collecting random fruit samples from unit areas and measuring seed weight after processing. Fruit size and shape, and the proportion of normal versus cull (crooks and nubs) fruits can also give some indications about seed yield. We determined some relationships among fruit and seed characteristics of 5 pickling, 2 parthenocarpic pickling, 1 Belt Alpha and 2 field slicer types of cucumbers in 3 years of seed yield trials using multi-correlation analysis.
Though the years were different in fruit and seed yield, the correlations among fruit and seed properties showed good congruency, except for one parthenocarpic pickling line. For this reason data were summed over years.
The majority of the fruits were uniform in shape due to use regular irrigation. As a result, we obtained high correlations among fruit characteristics such as weight, length, diameter, and seed cell diameter (data not shown). Also, high correlations were measured between the seed weight and seed number per fruit. High or medium correlations occurred between seed weight per fruit and fruit weight or seed weight per fruit and fruit length in short-fruited lines, while in slicing types these relationships were loose or uncorrelated. This tendency was more pronounced in the comparison of seed number per fruit and fruit size. No plump seeds were found beyond 20 cm from the basal end of the longest (26 to 28 cm) fruits. This supports the theory of competition between pollen tube growth and initial fruit elongation during fertilization in long-fruited slicers (1).
Seed extraction ratio (the quotient of seed weight and fruit weight) was not a good predictor of seed yield itself, but its average is typical for each line. Good seed set improves this ratio, especially in lines with short fruit and thin skin.
On the basis of our result, no clear conclusion could be drawn for thousand-seed weight and fruit weight or fruit dimensions. Generally, no correlation was measured for maximum thousand-seed weight and highest seed numbers in a fruit. On the other hand some differences occurred among years in the size of the correlations.
The average line had relatively high coefficients of variation (40 to 50%) for seed weight and seed number per fruit, seed extraction ratio and average fruit weight, while low coefficients of variation (<20%) occurred for fruit length, fruit diameter, seed cell diameter and thousand-seed weight.
Table 1. Correlation coefficients among fruit and seed characters of 10 cucumber lines over 3 years in seed production field trials.
Line |
Mean |
Seed wt./fruit |
Seed no./fruit |
Seed extraction ratio |
1000-seed weight |
|||||||||
|
fruit length (cm)
|
vs. Fruit wt.
|
vs. Fruit len.
|
vs. Seed no.
|
vs. Fruit wt.
|
vs. Fruit len.
|
vs. Seed wt.
|
vs. Seed no.
|
vs. Fruit wt.
|
vs. Fruit no.
|
vs. Fruit wt.
|
vs. Fruit len.
|
vs. Seed wt.
|
vs. Seed no.
|
|
Monoecious pickling |
||||||||||||||
|
K. livme
|
15.0
|
0.93
|
0.83
|
0.95
|
0.83
|
0.78
|
0.34
|
0.45
|
0.03
|
-0.01
|
0.80
|
0.70
|
0.73
|
0.51
|
|
K. 4599
|
14.6
|
0.90
|
0.78
|
0.92
|
0.73
|
0.63
|
0.54
|
0.68
|
0.15
|
0.05
|
0.61
|
0.59
|
0.48
|
0.14
|
Gynoecious pickling |
||||||||||||||
|
F 1040
|
13.2
|
0.70
|
0.70
|
0.94
|
0.54
|
0.59
|
0.70
|
0.77
|
0.02
|
0.15
|
0.44
|
0.36
|
0.19
|
-0.10
|
|
LV 19
|
14.5
|
0.84
|
0.73
|
0.99
|
0.71
|
0.62
|
0.66
|
0.72
|
0.22
|
0.15
|
0.38
|
0.31
|
0.13
|
-0.16
|
|
64 H
|
14.3
|
0.84
|
0.73
|
0.93
|
0.70
|
0.62
|
0.56
|
0.63
|
0.18
|
0.05
|
0.62
|
0.56
|
0.38
|
0.09
|
Parthenocarpic pickling |
||||||||||||||
|
76 C
|
11.8
|
0.66
|
0.55
|
0.98
|
0.62
|
0.51
|
0.73
|
0.72
|
0.10
|
0.04
|
0.08
|
-0.03
|
0.08
|
-0.09
|
|
KP 79
|
12.0
|
0.65
|
0.60
|
0.93
|
0.49
|
0.45
|
0.58
|
0.66
|
-0.11
|
-0.10
|
0.38
|
0.38
|
0.14
|
-0.15
|
|
Beit Alpha
|
||||||||||||||
|
FWIW
|
15.3
|
0.57
|
0.46
|
0.95
|
0.38
|
0.30
|
0.65
|
0.73
|
-0.15
|
-0.15
|
0.44
|
0.42
|
0.29
|
0.02
|
Semi-long slicing |
||||||||||||||
|
VA 1717
|
22.1
|
0.58
|
0.48
|
0.96
|
0.43
|
0.34
|
0.66
|
0.76
|
-0.16
|
-0.15
|
0.49
|
0.52
|
0.12
|
-0.12
|
|
JSW
|
22.6
|
0.46
|
0.38
|
0.94
|
0.24
|
0.19
|
0.57
|
0.73
|
-0.40
|
-0.41
|
0.48
|
0.44
|
0.13
|
-0.16
|
Literature Cited
- Nijs, A. P. M. den and P. Milotay. 1984. Pollination and fertilization in pickling and slicing cucumbers. Proc. Sexual Reproduction of Seed Plants, Ferns, Mosses. Wageningen 20-24, August 1984.