Effects of Plant Density and Sowing Date on the Growth, Flowering and Quantity of Essential Oil of Calendula Officinalis L

Full Length Research Paper

Effects of plant density and sowing date on the growth, flowering and quantity of essential oil of Calendula officinalis L.

Ahmad Reza Berimavandi 1*, Davood Hashemabadi 2, Mohammad Vali Facouri Ghaziani 2 and Behzad Kaviani 2

1Department of Agronomy, Rasht Branch, Islamic Azad University, Rasht, Iran. 2Department of Horticultural Science, Rasht Branch, Islamic Azad University, Rasht, Iran.

Accepted 6 July, 2011

Pot marigold ( Calendula officinalis L.) is a medicinal and ornamental plant. In an experiment which was designed in factorial on the basis of completely randomized block design with 3 replicates in 36 plots. The effects of plant density (20, 40, 60 and 80 plants/m 2- factor A) and sowing date (April 19 and 29, and May 10, 2010- factor B) were evaluated on the growth, flowering and essential oil of C. officinalis L. Studies were carried out on experimental field in Islamic Azad University, Rasht, Iran. Investigated characteristics were: plant dry weight, flower number/plant, branch number/plant, flower dry weight, flower yield/area unit, and quantity of essential oil. Maximum of plant dry weight (35.67 g), flower number/plant (25.88), branch number/plant (9.44), flower dry weight (3.72 g), and amount of essential oil/100 g dried flower (0.16 ml) were obtained at the 20 plants/m 2, while maximum of flower dry weight (132.07 g), and amount of essential oil (0.19 ml), both per area unit were obtained at the 60 plants/m2. The effect of sowing date for all characteristics was not significant. Interaction between plant density and sowing date was significant for all characteristics and the best treatments were the 20 plants/m 2 on 19 and 29 April.

Key words: Dry weight, flower production, pot marigold, Iran.

INTRODUCTION

Calendula officinalis L. (Asteraceae) is an annual, used for food and medicine (Hamburger et al., 2003; aromatic, medicinal and ornamental herb with yellow and Janke, 2004; Jimenez-Medina et al., 2006). Plant density orange flowers, a native to Mediterranean region (Gazim and sowing date are the two most important factors that et al., 2008). The composite flowers blossom in the affect directly on the yield and flower number, amount of spring-summer seasons three times per year (Gilman essential oils and yield components (Marisol et al., 2003). and Howe, 1999; Omidbaighi, 2005). The leaves and Plant density is dependent on the plant characters, flowers of marigold are applied in horticulture, medicine, growth period, time and method of cultivation, soil cosmetics, perfume, pharmaceutical preparation, food conditions, plant length, sun light and weeds. Selection of and other industries (Marczal, 1987; Muusa et al., 1992; suitable sowing date has advantages in relation to Van Wyk and Wink, 2004; Gazim et al., 2008). One of the assembling the raw material and other productions. It can main components of active ingredient in C. officinalis L. be accomplished by choosing the right plant species, soil, are essential oils, which most of them synthesize in its sowing date, plant nutrition, harvest etc. Early cultivation orange petals (Omidbaighi, 2005). Flower essence is of C. officinalis L. causes frost-bite and finally weakly establishment of plant in spring. Also, late cultivation causes shorten of growth period and simultaneous flowering period with very high temperature in summer *Corresponding author. E-mail: [email protected]. (Cromack and Smith, 1988). Seghatoleslami and Tel: 00989111495008. Mousavi (2009) evaluated the effect of three sowing Berimavandi et al. 5111

dates (March 30, April 14 and 30) and three row spacing Totally, flowers were harvested at 3 stages, and total dry weight calculated as yield. After determination of flower, dry weight/plant in (10, 20 and 30 cm) on C. officinalis L. flowering and 2 showed that the plant density and sowing date had density of 20, 40, 60 and the 80 plants/m , yield/area unit was calculated by following equation: significant differences on plant dry weight and seed yield. A study on the other species from Asteraceae family Flower yield/m 2 = number of plant/m 2 × flower yield/plant confirmed these results (Jamshidi, 2000). Study of Marisol et al. (2003) on the influence of sowing date on Flower number/plant and stem number/plant were obtained by the yield of capitula of C. officinalis L. during two growing account of five plants from center of each plot. For determination of seasons showed that in the first year of production the the essential oil, the plant materials (flowers) were dried in 45°C. The essential oil was obtained in a Clevenger apparatus by steam highest capitula yield was obtained in the treatment sown distillation. Thus, the 50 g of dried plant materials was extracted on June 4. In the second year, there was no difference in with 1000 ml of water. The water collected was re-extracted with 0.5 yield between sowing dates, and the average dried ml hexane. The essence and hexane was separated from water capitula yield was 3685 kg/ha. The sum total yield of the physically and weighted until the plant essence was obtained. Data two growing seasons was 4594 kg/ha of dried capitula. processing of the results was carried out by an EXCEL. Analysis of Martin and Deo (2000) demonstrated that the highest variance (ANOVA) was done using SPSS statistical software and means were compared using Duncan's test. flower yield in C. officinalis L. was obtained in density of

40 plants/m 2 and sowing date of April 15. Sowing date affects on quantity and quality of secondary metabolites RESULTS AND DISCUSSION (Jamshidi, 2000). There are several reports about the effect of genetically and environmental factors on The overall results of the effects of plant density and essential oils of C. officinalis L. (Miguel et al., 2004; sowing date on number of flower/plant, flower dry Danielski et al., 2006; Okoh et al., 2008). Plant density, weight/plant, flower dry weight/area unit, dry weight/plant, sowing date and plant age are effective factors on stem number/plant and amount of essential oil/plant are quantity and quality of essential oils in plants (Okoh et al., summarized in Table 2. 2007; Morteza et al., 2009). In this paper, the effect of plant density and sowing date on the growth, flowering and quantity of flower’s essential oil of C. officinalis L. Number of flower/plant have been discussed. Based on analysis of variance (Table 3), the effect of plant density on the flower number/plant was significant MATERIALS AND METHODS at 0.01 level of probability. There is no significant

Seeds of marigold ( C. officinalis L.) were prepared from Pakan Bazr difference in the flower number/plant due to the effect of Co., Isfahan, Iran. Investigation was carried out on experimental sowing date (Table 3). The effect of interaction of plant field in Islamic Azad University of Rasht branch, Iran (N 37° 10’ 5.5’’ density and sowing date on the number of flower/plant and S 45° 33’ 12.6’’; altitude, 73 m above sea level; mean annual was not significant according to the analysis of variance rainfall, 1348 mm; mean annual temperature, 15°C) from 19 April to 2 but was significant according to the mean comparison 10 May (three times). Plot area was 6.3 m (3.5 m × 1.8 m), totally; (Table 2). This means that the interaction of plant density 36 plots and total surface was 376.2 m. Initially, chemical fertilizer including; urea-superphosphate triple-potassium chloride and sowing date on the flower number/plant was no (222.5:133.5:120 kg/ha) and manure (40 ton/ha) was applied to the significant, but the difference between different levels of main plots at planting time. Distance between plots and blocks were density × sowing date was significant. The highest flower 0.5 and 1 m, respectively. Used plant spacing was 12.5, 6.25, 4.2 2 number/plant was obtained from density of the 20 and 3.1 cm for plant density (D) of 20, 40, 60 and 80 plants/m , plants/m 2 (25.88 flowers/plant) in different levels of plant respectively; row distance was 40 cm. Sowing dates (S) were April 2 19 and 29, and May 10, 2010. Thinning was performed 2 weeks density, and the 20 plants/m × sowing date of April 19 after cultivation. Irrigation was carried out in 8 days intervals, when (28.33 flowers/plant) in different levels of interaction there was no rainfall. Hoeing was conducted in three stages: 15, 30 effects (Table 2). The highest flower number/plant was and 45 days after planting. The chemical analysis of the growing obtained in the lowest plant density because; (1) medium is presented in Table 1. Experiment was designed in Decreasing of competition between plants, (2) increasing factorial test on the basis of completely randomized block design of light and materials absorption by each plant resulting in with 3 replications. Interaction of two factors; sowing date (April 19 and 29, and May 10) and plant density (20, 40, 60 and 80 the increase of the flower number/plant. Decreasing of plants/m 2) (totally, 36 plots) were used in this experiment. Dry light and materials in high plant density and late sowing weight/plant (g), flower dry weight/area unit (g), flower are two main factors for severe decreasing of flower in number/plant, stem number/plant, yield/area unit, amount of plant density of the 80 plant/m 2 and sowing date of May essential oil/plant, and amount of essential oil/area unit were 10. Some studies confirm our findings. Studies of Lotfi evaluated. For determination of dry weight, five plants were Jalalabadi et al. (2006) on C. officinalis L. showed that selected from the center of each plot, cut from crown and then dried in oven at 72°C, following obtaining of fresh weight. For the effect of plant density on the flower number/plant was determination of flower dry weight, five plants was selected from significant at 0.01 level of probability. Martin and Deo center of each plot, dried for 6 h at 35 to 45°C and then weighted. (2000) revealed that the highest and the lowest flower 5112 J. Med. Plant. Res.

Table 1. The main chemical properties of the growing medium.

Soil texture Nitrogen (%) Phosphorus (ppm) Potassium(ppm) Organic matter (%) EC (mmhos/cm) pH Soil depth (cm) Clay 0.3 7 84 0.7 0.59 6.33 0-30

Table 2. Effects of plant density and sowing date on the quantity and quality traits of Calendula officinalis L.

Flower Flower dry Flower yield Dry weight Essence (ml/100 g Stem Essence/area unit Treatments number/plant weight/plant (g/area unit) (g/plant) dry flower) number/plant (ml) S1 19.75 a* 2.63 a 108.91 a 25.96 a 0.150 a 7.46 a 0.160 a S2 19.83 a 2.57 a 110.18 a 25.21 a 0.150 a 7.17 a 0.160 a S3 20.17 a 2.59 a 112.93 a 26.29 a 0.150 a 7.75 a 0.170 a D1 25.88 a 3.74 a 75.00 c 36.64 a 0.160 a 9.44 a 0.135 c D2 21.00 b 2.95 b 118.57 b 30.79 b 0.150 b 8.22 b 0.185 ab D3 18.11 c 2.24 c 132.07 a 20.54 c 0.147 c 6.67 c 0.190 a D4 14.67 d 1.45 d 117.06 b 14.85 d 0.140 d 5.44 d 0.162 b S1D1 28.33 a 4.10 a 85.00 c 41.06 a 0.157 a 10.67 a 0.133 c S1D2 23.33 b 3.26 b 130.70 a 34.79 a 0.157 a 9.34 a 0.205 a S1D3 22.00 b 2.51 c 141.00 a 27.68 b 0.153 b 7.34 c 0.216 a S1D4 17.00 c 1.81 d 149.60 a 18.73 c 0.143 c 6.00 d 0.214 a S2D1 26.00 a 3.77 a 76.33 c 37.51 a 0.153 b 9.67 a 0.117 c S2D2 21.00 b 3.03 b 120.53 a 30.76 b 0.153 b 7.67 b 0.185 a S2D3 16.33 c 2.17 c 130.40 a 19.82 c 0.147 b 7.00 c 0.191 a S2D4 14.00 d 1.30 d 104.27 b 14.17 d 0.137 c 5.67 d 0.142 c S3D1 23.33 b 3.16 b 63.67 c 31.36 b 0.157 a 8.00 b 0.099 c S3D2 18.67 c 2.56 c 104.53 b 26.82 c 0.150 b 7.67 b 0.156 b S3D3 16.00 d 2.05 c 124.80 b 14.13 d 0.140 c 5.67 d 0.174 b S3D4 13.00 d 1.22 d 97.33 b 11.67 d 0.140 c 4.67 d 0.137 c

*In each column, means with the similar letters are not significantly different at 5% level of probability using LSD test.

number/plant in C. officinalis L. were obtained on the growth and flower production of C. effect in increasing flower number of C. officinalis from the density of the 9 plants/m 2 (18.60 flowers/ officinalis L. demonstrated that the highest flower L. Studies of Morteza et al. (2009) showed that plant), and 332 plants/m 2 (2.1 flowers/plant), number/plant obtained in density of 45 × 45 cm. sowing date and planting density of Valeriana respectively. Studies of Mili and Sable (2003) on Ganjali et al. (2010) showed that sowing date on officinalis L. significantly affected flowering stem the effect of planting density and nitrogen levels April 1st and plant density of 12 × 50 had the most number. The highest flowering stem number was Berimavandi et al. 5113

Table 3. Analysis of variance (ANOVA) for the effect of plant density and sowing date on the quantity and quality traits of Calendula officinalis L.

Means of square Source of df variation Flower Flower dry Flower dry Dry Stem Amount of Amount of number/plant weight/plant weight/area unit weight/plant number/plant essence/plant essence/area unit Sowing date (S) 2 0.583 ns 0.014 ns 50.60 ns 2.230 ns 1.028 ns 1.111 ns 0.000 ns Plant density (D) 3 202.991** 8.684** 5500.849** 869.430** 27.63** 0.000** 0.010** S × D 6 0.402 ns 0.011 ns 71.077 ns 3.657 ns 0.435 ns 5.556 ns 0.000 ns Error 22 2.189 0.051 144.113 3.363 0.505 4.672 0.000 cv (%) 7.4 8.7 10.84 7.14 9.55 4.58 7.4

**: Significant at α = 1%, *: Significant at α = 5%, ns = Not significant.

achieved under the 12 plants/m 2 planting density and 10 number/plant. Increasing of yield/area unit is caused of August sowing date. increase of plant canopy (near to suitable density), and high capacity of light absorbance. Studies of Rahmani et al. (2003) on the effect of planting density and nitrogen Flower dry weight/plant levels on dry flower yield of C. officinalis L. demonstrated the yield increases by increasing the plant density from The effect of plant density on the flower dry weight/plant the 20 to 50 plants/m 2. Martin and Deo (2000) was significant at 0.01 level of probability (Table 3). The investigated the effects of planting density on flower highest value (3.74 g dry flower weight/plant) was yield/area unit of C. officinalis L. and they concluded that obtained by using the 20 plants/m 2 (Table 2). Martin and the highest yield was accomplished with the 101 plant Deo (2000) revealed that total flower yield of C. officinalis density/m 2 (171 g flower dry weight/m 2). Studies of Lotfi L. was not significantly different at populations over the Jalalabadi et al. (2006) on C. officinalis L. showed that 46 plants/m 2, but declined with lower plant populations. the effect of plant density on the number and dry weight The interaction of plant density and sowing date on the of flower was significant at 0.05 level of probability. flower dry weight/plant was not significant (Table 3). The highest value (4.10 g dry flower/plant) was obtained by using the 20 plants/m 2 × sowing date of April 19 (Table Dry weight/plant 2). Kišgeci (2002) and Draži ć (2004) showed that the optimal row spacing for C. officinalis L. sowing are 40 to The effect of different plant density on the dry 50 cm, while Stepanovi ć (1998) and Šilješ et al. (1992) as weight/plant was significant at 0.01 level of probability optimal row spacing quote 50 to 60 cm. Martin and Deo (Table 3). The highest dry weight (36.64 g dry (2000) investigated the crop density effects and they weight/plant) was obtained by using the 20 plants/m 2 concluded that the higher yield was accomplished with (Table 2). The interaction of plant density and sowing the 332 plants/m 2. Results of Cromack and Smith (1988) date on the dry weight/plant was not significant (Table 3). indicated that density over the 40 plants/m 2 had no effect The highest dry weight/plant (41.06 g) was obtained by on yield. using the 20 plants/m 2 × sowing date of April 19 (Table 2). Low density and late cultivation increased the plant dry weight which is the reason for plant competition. Flower dry weight/area unit Studies of Martin (2000) on C. officinalis L. showed that the harvest index was decreased in line with the The data presented in Table 3 indicated that, the effect of increasing of plant density. Its reasons are decrease in plant density on the flower dry weight/area unit was the plant biomass and branches number. In plant density significant at 0.01 level of probability. The most flower dry of the 9 and 332, harvest index were 0.26 and 0.31, weight (132.07 g dry flower/m 2) was obtained by using respectively. Gomes et al. (2007) demonstrated the the 60 plants/m 2 (Table 2). The interaction of plant effects of plant density and arrangement on C. officinalis density and sowing date on the flower dry weight/area L. yield. unit was not significant. The most flower dry weight (149.6 g dry flower/area unit) was obtained by using the 80 plants/m 2 × sowing date of April 19 (Table 2). Stem number/plant Increasing of plant density causes decreasing of flower dry weight/plant and increasing of flower dry weight/area Plant density had significant effect on stem number/plant unit. Increasing of density had direct effect on the flower (p ≤0.01) (Table 3), and the largest stem number/plant number/area unit and adverse effect on the flower (9.44) was obtained in density of the 20 plants/m 2. 5114 J. Med. Plant. Res.

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