Effect of pre-sowing treatment on seed germination of Ixora coccinea L

Ixora coccinea L. belongs to family Rubiaceae. Commonly, it is called as pendkul in Konkan region and also known as a flame of woods. Many species of Ixora are cultivated for ornamental purpose. I. coccinea L. is found in the coastal region, ghat region, and also associated with mangroves of Sindhudurg and Ratnagiri district. The flowers are scarlet red, therefore cultivated in tropical and subtropical areas for ornamental purpose (Kirtikar and Basu, 1935; Latha et al., 2001). Flowers are used in the treatment of dysentery and eruption. Roots of this plant are used to cure ulcer, fever, hiccough, and nausea (Alam, 2014). In Indian villages and tribal areas, fruits are eaten by children’s, local folks, and tribes (Nazarudeen, 2010). I. coccinea L. possesses a number of medicinal properties. Flowers, leaves, stem, and roots of this plant are used in Ayurveda, in folk medicines, and in the traditional system of medicine. Regular consumption of fruits is helpful to people having problem of diabetes and obesity (Baliga and Kurian, 2012). Focusing on medicinal potential of I. coccinea, germination studies were undertaken to obtain maximum seed germination. Seeds were treated with different chemicals for various period. Treatment of distilled water, cold water, hot water, and gibberellic acid (GA) was compared for best results. MATERIALS AND METHODS


INTRODUCTION
Ixora coccinea L. belongs to family Rubiaceae. Commonly, it is called as pendkul in Konkan region and also known as a flame of woods. Many species of Ixora are cultivated for ornamental purpose. I. coccinea L. is found in the coastal region, ghat region, and also associated with mangroves of Sindhudurg and Ratnagiri district. The flowers are scarlet red, therefore cultivated in tropical and subtropical areas for ornamental purpose (Kirtikar and Basu, 1935;Latha et al., 2001). Flowers are used in the treatment of dysentery and eruption. Roots of this plant are used to cure ulcer, fever, hiccough, and nausea (Alam, 2014). In Indian villages and tribal areas, fruits are eaten by children's, local folks, and tribes (Nazarudeen, 2010). I. coccinea L. possesses a number of medicinal properties. Flowers, leaves, stem, and roots of this plant are used in Ayurveda, in folk medicines, and in the traditional system of medicine. Regular consumption of fruits is helpful to people having problem of diabetes and obesity (Baliga and Kurian, 2012). Focusing on medicinal potential of I. coccinea, germination studies were undertaken to obtain maximum seed germination. Seeds were treated with different chemicals for various period. Treatment of distilled water, cold water, hot water, and gibberellic acid (GA) was compared for best results.

MATERIALS AND METHODS
Fruits of I. coccinea were collected from Achara, Sindhudurg district of Maharashtra. Fruits are berry type single fruit contains two seeds. Seeds are small and endospermic (Plates 1 and 2). Fruits are collected in May 2014 and weighted dried under natural sunlight. Healthy dried seeds were selected for the experiment. Healthy seeds were subjected to viability test through the floating method, in which floated seeds were considered as unviable, and the seeds were discarded. The experiment was carried out during June 2014 to December 2014 and after soaking seed germination studies were continued up to 45 days.
Experimental trials were standardized as follows: Healthy seeds of I. coccinea were selected for experiment and sterilized with 0.1% HgCl 2 for 10 min, then washed thoroughly with distilled water and treated with different treatments. 1. Soaking seeds in water for 1 and 2 days (Khosh-Khui and Kaviani, 2006) 2. Hot water treatment 3. Seeds were treated with germinator solution: 40% of germinator solution was used for the soaking, and after 6 h, the seeds were thoroughly washed with tap water and placed for germination Effect of pre-sowing treatment on seed germination of Ixora coccinea L.
4. Treatment of GA (Thomas, 1994) 5. Control: Set of control seeds was maintained separately. These experiments were conducted in sterilized glass Petri plates which were filled with 10 mL distilled water. To avoid fungal infection, the filter paper and media were changed frequently after 1 or 2 days (Thomas, 1994), each Petri plate having 20 seeds and repeated in triplicates. A seed was considered sprouted when it discharges radical of 2 mm (Sayar et al., 2010). The daily observation was recorded, the results were compiled separately, and the percentage germination was calculated separately.

Data Analysis
The set of experiment was arranged in complete randomized design and consist of three replicates. The data were subjected to statistical analysis of variance (ANOVA) and t-test for testing significant difference in pair of treatments using Microsoft Excel. ANOVA two factors without replication were carried out to analyze the data and determine most appropriate pre-treatment method for higher germination percentage in I. coccinea seeds.

Germination Percentage (%) of I. coccinea to Different Treatments
Seeds of I. coccinea treated with germinator solution, hot water treatment 1 day, 2 days soaked in cold water, and germination percentage were represented in Figure 1.
ANOVA was done from the values of Figure 1  Seeds of I. coccinea soaked in germinator showed early germination as compared to other treatments and control. Hot water treated seeds showed germination after 14 days and also showed higher germination percentage after 45 days (85%). Seeds of Ixora treated with germinator solution germinate after 9 days and 70% germination after 45 days. Seed germination under different soaking period gave fair germination percentage (35%), this was not significant within the treatments. 1 and 2 days soaking in water treatment showed lower germination percentage than control, these results were similar to pre-treatment to Afzelia africana seeds (Amusa, 2011), and control treatment showed higher germination percentage because over soaking seeds of Jubaeopsis caffra in water reduce germination through oxygen deficiency (Robertson and Small, 1977). However, Owonubi et al. (2005) suggested that seeds of Azadirachta indica soaked in cold water for 1 and 12 h showed an increasing rate of seed germination.
Plate 2: Seeds of Ixora coccinea L. Okonwu and Eboh (2017) reported that C. verrucosa seeds treated with HCl, sodium nitrate, and hot water showed higher germination percentage as compared to control. Usman et al. (2010) reported that seeds Acacia senegal treated with hot water for 10 min showed best results in higher germination percentage. Sanyang et al. (2008) concluded that seeds of A. senegal treated with hot water for 10 min showed early germination. Seeds of Albizia julibrissin treated with hot water, soaking in warm water at 40°C and 50°C, and soaking period were 1-6 h. Seeds soaking in 40°C and 50°C showed 86-91% germination (Merou, 2011). Ixora seeds treated with hot water and showed 85% germination, this result close to Albizia results.
ANOVA was done from the values of Figure 2 using Microsoft Excel. The obtained values of F statistics as F 3, 6 = 16.99. Calculated F is 16.99≥ table F 3.28 and P value is smaller than 0.05 and calculated F is greater than table F, so again, here rejected the null hypothesis. There is significant difference in treatments. By applying, t-test for testing significant difference in pair of treatments. Ltl = −3.469 is greater than critical value 2.57 and P value is smaller than 0.05. Therefore, from average values, it is said that 100 ppm GA showed higher germination percentage.
Seeds of I. coccinea treated with GA start germination after 19 days, but untreated seeds showed early germination and started germination after 14 th days. 100 ppm GA treated seeds showed higher germination percentage, and it was 90% (Figure 2). Seeds treated with 200 ppm GA showed lower germination percentage 13.33% as compared to control (Plate 3). Singh and Murthy (1987) reported that GA at higher concentration increases germination percentage in of Cassia obtusifolia. Gunasekarn et al. (2001) concluded that 100 ppm GA showed higher germination of nutmeg, these results tandem with present investigation. GA plays an important role to stimulate germination and lower down the difference in onset and final germination which promote to increase the hydrolytic activity (Joshi and Dhar, 2003;Manjkhola et al., 2003). Shivanna et al. (2007) have noticed that GA and indole-3acetic acid showed higher germination. In process of seed germination, gibberellins are played an important role to stimulate the growth of embryo (Hedden, 2017).

CONCLUSION
The best method for I. coccinea seed germination is 100 ppm GA. The maximum percentage was obtained in the treatment of hot water and germinator solution. However, among all the methods, 100 ppm GA and hot water treatment are found to be suitable for I. coccinea seeds for better results with maximum germination. For mass propagation and conservation point of view, hot water treatment is more suitable. Furthermore, without any chemicals, the plantlets of Ixora can be raised and domesticated. Thus, the eco-friendly protocol has been developed for I. coccinea.