Evaluation of Seed Yield of Pickling and Slicing Cucumbers in the Field Affected by Year and Plant Density

Cucurbit Genetics Cooperative Report 14:12-14 (article 5) 1991

P. Milotay and S.A. Hodosy
Vegetable Crops Research Institute, 6000 Kecskemet, Hungary

Experimental lines of cucumber are generally propagated in glasshouses, plastic houses or in net-covered cages. These circumstances rarely provide appropriate estimates of seed yield under field conditions.

During seed production of pickling and slicing cucumbers in the field, an average of 100 to 200 seeds per fruit is usually obtained. However, practical seed producers frequently conclude that seed producers frequently conclude that environmental factors influence seed yield most, while genotype receives little attention.

Methods. Two small studies were designed to measure seed yielding capacity of F5 to F7 cucumber lines of different origin. Lines were chosen to represent different vine length, fruit, type, sex type, and levels of parthenocarpy. Experiment 1 had normal (7.8 plant/m2) density, and was run for four years (1987 and 1990) with 2 replications. Experiment 2 had normal density initially, but was thinned to 3.8 plant/m2. It was run for two years (1988 and 1989) with 2 replications.

The lines tested were (average fruit length in parentheses): K livme (a50 mm) and K. 4599 (146 mm) monoecious pickling type: F 1040 (132 mm), LV 19 (145 mm) and 64H (143 mm) gynoecious pickling type; 6C (118 mm) and KP 79 (120 mm) parthenocarpic pickling type; FWIW (153 mm) gynoecious Beit Alpha type; JSW (226 mm) and VA 1717 (221 mm) semi-long, slightly parthenocarpic, gynoecious field slicers. Plots were sown between 15 and 20 May in succeeding years. The 5.8 m2 randomized plots were irrigated by sprinklers. Normal cultural practices were observed. At seed maturity, a random sample of 15 fruits per plot was collected, and seeds were processed by hand.

Results. According to the analysis of variance, the highest variation can be attributed to year for fruit yield, seed yield and thousand seed weight (Tables 1 and 2). The fruit characteristics such as average fruit weight, fruit length, fruit diameter, fruit length/diameter ratio, fruit diameter, and seed cell diameter were measured for the genotypes at each extreme.

Number of seeds per fruit was influenced by genotype and year. Low plant density (3.8 plant.m2) reduced the fruit and seed yield per m2 at the majority of the lines. On the other hand, a slight increase in fruit size and thousand seed weight was observed. Larger influence of plant density was displayed only in fruit number (data not shown). Considering plant density, the normal (7.8 plant/m2) spacing gave higher seeds yield.

The variation in seed number per fruit (Table 3.) was similar to the results of Wehner and Horton (2). In our trial we did not find more seeds in slicers than in short fruited types. On the other hand, small fruit size did limit seed yield in the case of parthenocarpic pickling types.

On the basis of our data, year was the most significant factor influencing fruit and seed yield, similar to the findings of Wehner and Swallow (1). The highest variation was found in both trials in the average of the lines over years in seed yield, followed by fruit yield, seed number per fruit, fruit number and thousand seed weight. It appears that vine growth and fruit bearing capacity of the genotype are more important than seed number per fruit.

Table 1. Analysis of variance for fruit and seed yields for four years.

Source of variation

df

Fruit yield

Seed yield

Seed number per fruit

df

Thousand seed wt.

Total 79 4.23 522.8 2027.7 59 10.08
Replication 1 2.24 280.5 2.5 1 6.90
Treatment 39 7.44*** 839.0*** 3424.9*** 29 18.31***
Lines 9 18.63*** 1304.5*** 9288.4*** 9 27.63**
Years 3 21.26*** 3786.8*** 4095.8* 2 95.95***
L x Y 27 2.18* 356.3 1392.4* 18 5.02*
Error 39 1.09 212.7 682.0 29 1.97

*, **, *** = significant at 5, 1 and 0.1% levels, respectively

Table 2. Analysis of variance for fruit and seed yields for two years and at two plant densities.

Source of variation

df

Fruit yield

Seed yield

Seed number per fruit

Thousand seed wt.

Total 79 5.12 645.3 1.18 11.11
Replication 1 1.64 282.3 0.91 4.18
Treatment 39 8.74*** 1118.5*** 2.10*** 20.22***
Lines (L) 9 21.58*** 1550.4*** 2.95*** 37.81***
Years (Y) 1 70.70*** 17207.6*** 35.02*** 278.59***
Density (D) 1 14.15** 2141.5** 1.30* 9.67*
L x Y 9 4.47* 828.9*** 1.39*** 12.58***
L x D 9 0.72 133.9 0.33 1.40
L x D 1 0.10 1.9 1.01 11.54
L x Y x D 9 1.65 150.1 0.28 2.51
Error 39 1.60 199.6 0.28 2.19

*, **, *** = significant at 5. 1 and 0.1% levels, respectively.

Table 3. The influence of years on fruit and seed yield of 10 cucumber lines.

Line

Year

Fruit wt. kg/m²

Fruit no./m²

Seeds per fruit

Seed yield g/m²

Thousand seed wt. (g)

K. livme 1987 2.80 12.1 171.1 41.3 19.86
1988 6.60 21.1 201.8 89.7 21.19
1989 4.13 16.6 157.0 42.9 16.75
1990 5.22 18.7 185.6 76.0 21.63
K4599 1987 4.05 15.8 224.7 63.6 17.98
1988 6.41 24.8 181.5 85.8 18.99
1989 3.98 15.9 174.8 46.7 16.62
1990 6.22 19.5 228.3 93.2 20.88
F1040 1987 2.40 10.9 123.9 29.7 22.10
1988 5.19 19.2 171.1 75.7 23.40
1989 3.00 15.0 112.1 31.4 18.68
1990 4.74 16.6 173.1 69.3 24.23
64H 1987 5.08 18.9 159.3 68.6 22.68
1988 4.94 19.5 140.4 64.1 24.07
19889 6.46 20.4 154.0 73.1 23.24
1990 5.41 19.2 135.5 59.8 23.11
LV 19 1987 4.37 20.8 122.3 53.3 21.05
1988 5.84 17.3 225.0 84.2 21.23
1989 4.36 15.9 152.8 50.2 20.91
1990 6.62 22.8 148.2 80.3 23.25
76C 1987 2.30 22.1 81.7 38.4 21.06
1988 1.08 9.9 117.6 22.7 22.69
1989 1.74 16.7 79.0 19.6 19.56
1990 2.84 23.3 75.0 22.8 22.78
KP79 1987 2.95 23.6 83.5 39.1 19.95
1988 3.13 21.3 131.7 66.9 24.05
1989 1.55 15.0 105.0 27.0 17.68
1990 2.46 20.8 74.2 32.5 21.12
FWIW 1987 3.41 14.8 150.1 45.4 20.70
1988 6.41 19.9 157.6 73.7 23.55
1989 3.06 13.6 78.8 19.7 18.34
1990 5.27 14.5 130.1 50.4 25.62
JSW 1987 5.07 15.4 171.0 64.5 24.41
1988 6.66 15.2 150.8 58.2 25.41
1989 3.07 11.4 127.5 35.2 23.96
1990 7.18 15.7 169.6 76.9 29.35
VA1717 1987 5.35 14.5 104.1 36.8 24.33
1988 10.40 20.5 177.6 82.7 22.75
1989 5.35 14.4 182.2 55.4 21.88
1990 7.46 17.1 135.7 65.1 28.37
LSD (5%) 2.10 6.1 52.8 29.4 2.86

Literature Cited

  1. Wehner, T.C. and W. H. Swallow. 1986. Optimum allocation of plots into years, seasons, locations and replications for once over harvest trials of cucumber. Cucurbit Genet. Coop. Rpt. 9: 44-46.
  2. Wehner, T. C. and R.R. Horton. 1988/ Number of seeds per mature fruit for different types of cucumber. Cucurbit Genet. Coop. Rpt. 11:15-16.