Effects of Calcium on Cucumber(Cucumis sativus L.) Seed Germination, Seed Storage and Seedling Growth

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Cucurbit Genetics Cooperative Report 19:23-24 (article 8) 1996

Huanwen Meng, Zhihui Cheng and Hongwen Cui
Department Horticulture, Northwestern Agricultural University, Yangling, Shaanxi 712100, P.R. China

Introduction. Calcium is not only a macroelement, but one of the major regulators of plant metabolism (2,3). It has been reported that soaking peanut seeds with 30 mmol/l of Ca2+ increases the germination percentage and vigor of maize seeds (1). The optimum Ca2+ concentration in these experiments was 10 mmol/l. We report here the effects of Ca2+ on cucumber seed germination, storage and seedling growth.

Material and Methods. Four concentrations of CaCl2 , (5 to 40 mmol/l), were used to coat cucumber seeds of ‘Jing 4-3-1’. Seed receiving no such treatment were used as the control. The germination percentage, rate and index 9of coated seeds and artificially aged coated seeds were evaluated in a temperature cabinet at 35 C. Artificial aging of seed was accomplished by seed treatment in a closed container held at 42 C and a relative humidity of near 100%. Measurements were taken from seedlings grown in vermiculite medium and ambient light, temperature and humidity.

Results and Discussion. A Ca2+ concentration of 10 mmol/l was optimal for seed germination. Higher (40 mmol/l) and lower (5 mmol/l) Ca2+ concentrations did not promote germination. The germination percentage, germination rate and germination index of seeds coated with 10 mmol/l Ca2+ were 9.4%, 10.9% and 6.6% higher, respectively, than control. The difference in germination percentage between treatment and control was statistically significant. A germination index of 5 mmol/l Ca2+ was significantly lower than that of control (Table 1). All coated seed treatments (5-40 mmol/l) Ca2+ were more tolerant to storage than that of control (Table 2). The germination percentage, germination rate, and germination index of artificially aged coated seeds was 43.9-55.3%, 41.7-57.5% and 24.8-44.1% higher, respectively, than control. Significant differences between the treatments and control were recorded for germination percentage and germination rate. Although treatments were not significantly different, germination decreased as Ca2+ concentration was increased. Significant differences among treatments and between any treatment and the control were not detected for seedling height, leaf area and seedling index. The stem width of seedlings derived from seeds coated with 5 and 10 mmol/l Ca2+ were 16.7% and 3.3% larger, respectively, than control. The fresh weight of seedlings derived from seeds treated with these Ca2+ concentrations were 11.3% and 9.6% lower than control (Table 3).

In summary, Ca2+ concentration for cucumber seed coat treatment is between 5 to 20 mmol/l.

Table 1. Influences of Ca2+ seed coat treatment of cucumber seed on germination.

Ca2+ concentration (mmol/L)

Germination percentage (%)

Germination power (%)

Germination index
0 78.0 bAB 73.3a 17.38
5 77.3 bB 69.3 a 14.41 cB
10 85.3 aA 81.3 a 18.53 aA
20 82.7 abAB 78.0 a 16.38 bAB
40 81.3 abA.AB 71.3 a 16.18 bAB

Table 2. Germination of artificially aged 2+ coated seeds of cucumber.

Ca2+ concentration (mmo.il/L)

Germination percentage (%)

Germination power (%)

Germination index
0 (Control) 37.8 36.7 bB 8.12 a
5 58.9 aA 57.8 aA 11.70 a
10 58.7 aA 55.6 aA 10.52 a
20 54.4 aA 52.6 aA 10.13 a
40 56.7 aA 54.4 aA 10.42 a

Table 3. Effects of Ca2+ seed coating of cucumber seed on seedling growth.

Ca 22+conc. (mmol/L)

Height (cm)

Stem width (cm)

Fresh weight (g)

Leaf area (cm2)

Seedling index
CK 5.4 a 0.300 bB 2.287 aA 23.2 a 1.327 a
5 5.9 a 0.3465 aA 2.030 bA 24.6 a 1.087 a
10 5.7 a 0.310 bB 2.070 bA 23.2 a 1.077 a
20 5.7 a 0.300 bB 2.270 aA 23.0 a 1.337 a
0 5.2 a 0.300 bB 2.133 abA 23.3 a 1.237 a

Literature Cited

    1. Donglin, L. 1995. Application and effect analysis of soybean and seed coat. Modern Agriculture 6:23.
    2. Xizhang, S. and Changming, L. 1990. A new type of seed coat. Seed World 9:31.
    3. Songquan, S. 1991. Regulating effects of calcium on seed germination. Seed 5:34.