Received 20 November 2015; accepted 6 December 2015; published 11 December 2015

ABSTRACT

In order to study the germination pattern and root trainer technology for Terminalia arjuna, its seeds were procured from two places of central Kerala and their germination studies were conducted in six different sowing media using fresh, pretreated and seeds stored up to three months. Germination value (GV) for all the field trials was calculated that showed highest for fresh seeds without pretreatments sown in PBCP and RTCP. Maximum GV for pretreated seeds were recorded in control and in gibberellic acid (100 ppm) treated seeds sown in PBCP and RTCP. Analysis of variance shows significance at 1% level between medium, between pretreatments and between years of study. Transplantation shock, bulkiness, and frequent change of polythene bags cause additional labor by conventional method but root trainers have advantages such as requiring no change of medium, least possibility of transplantation shock, advantage of air pruning, prevention of root coiling due to antispiral design and requirement of small area which makes them suitable for mass production of seedlings.

Keywords:

Germination Value, Terminalia arjuna, Rooting Media, Root-Trainers

Subject Areas: Agricultural Science

1. Introduction

Indian forests of different types are always known for their multifarious functions, and hence form an important component of the life supporting system. During the last decade Indian government together with other governmental and non-governmental agencies have given more importance on the use of local species for plantation, as they are eco-friendly and environmentally safe [1] . This trend has increased the demand for planting material, including primarily local, indigenous, endemic and little known under-utilized plant species. Terminalia arjuna Wight & Arn. trees are commonly found throughout the greater part of the Indian Peninsula, from Avadh southwards, and in Southern, Western and Central India. It is also found in Sri Lanka [2] [3] . In Kerala it grows mainly along riverbanks in the dry deciduous forests [4] . The timber is used for carts, agricultural implements, water troughs, boat building and other domestic purposes. The bark is used in various medicinal preparations [4] . For the mass propagation of Terminalia arjuna, root trainer technique is important and hence this study concentrates on comparative germination results and interpretation in root trainers in addition to the traditional methods.

2. Materials and Methods

Mature fruits were collected from cultivated mother plants at Prof. T C Joseph memorial Garden (P2), Union Christian College, Aluva and from Peechi natural stands, Thrissur (P2). All experiments in the present study was conducted during 2007 (Y1), 2009 (Y2) till 2013 (Y3) in the nursery of T.C Joseph Memorial Botanical Garden, Department of Botany, Union Christian College, Aluva, +10˚7'30.65", +76˚20'3.32", Kerala State, India. Sample size for each germination trials using seeds samples from different sites, with and without pretreatments and in different medium of sowing was kept 100. The experimental trials using fresh seeds were repeated for three years (Y1, Y2 and Y3) and germination pattern of stored seeds were gathered up to three months at one months interval (M1, M2 and M3).

Germination studies of fresh seeds without pretreatments, with pretreatments and stored seeds up to 3 months at one-month intervals were carried out in six different media such as raised standard nursery bed (NB), germination tray with polyurethane sheets (GT), polythene bag with potting mixture (PBPM), polythene bags with coir pith (PBCP), root trainers with potting mixture (RTPM) and root trainers with coir pith (RTCP) and their results showing Germination Percentage, Percentage of sound seeds which do no germinated (obtained by embryo cut test), were obtained for each tests. Germination value was calculated by the formula by [5] . Number of seeds germinated in each day and the day taken for germination were recorded. Cumulative germination percentage was calculated for each treatment at the end of each trial. Germination value (GV) was calculated using the following formula as given by Czabator (1962).

where, GV is the germination value, Final MDG represents final mean germination, which is calculated at the cumulative percentage of full seed germination at the end of the test divided by number of days from sowing to the end of the test and PV is the peak value (the maximum mean daily germination recorded at any time during the test). Viability percentage was also calculated by using the equation Germination percentage + percentage of sound un-germinated seeds. At the end of the germination period, all remaining un-germinated seeds were cut and examined and the percentage of fresh, viable and possibly viable seeds was recorded as sound un-germi- nated seeds. All the germination percentages obtained were subjected to ANOVA study to make comparisons between media, year of study, place of seed collection, effect of pretreatments and effect of storage up to three months in all the study species.

3. Results

3.1. Fruit and Seed Characteristics

Fruit is a drupe, ovoid to obovoid, five winged, reddish brown, glabrous, 4 to 5 cm × 2.5 to 3 cm. On an average fruits weigh 296 to 425 per kilogram. Seeds are delicate with a leafy cotyledon and difficult to separate from the woody pericarp (Figure 1).

3.2. Germination Performance of Fresh Seeds in Different Sowing Media

Germination studies of fresh seeds without pretreatments, with pretreatments and stored seeds up to 3 months at one-month intervals were carried out in six different media such as raised standard nursery bed (NB), germination

tray (GT), polythene bag with potting mixture (PBPM), polythene bags with coir pith (PBCP), root trainers with potting mixture (RTPM) and root trainers with coir pith (RTCP) and their results showing Germination Percentage, Percentage of Sound Seeds which do no Germinated (obtained by embryo cut test), Viability Percentage, Peak Value (PV), Final Mean Daily Germination (MDG) FINAL, and Germination Value (GV) were obtained for each tests and tabulated (Tables 1-3).

In the germination study of fresh seeds without pretreatments, maximum sound seeds which did not germinate after the completion of germination was observed when sown in NB and the maximum viability percentage obtained was 69.43%, when seeds sown in RTCP. Highest Peak Value (PV), Final MDG and Germination Value were recorded in seeds when sown in RTCP. Germination value (GV) was minimum for seeds sown in NB (Table 1).

3.3. Effect of Pretreatments in the Germination of Fresh Seeds in Different Sowing Media

In the germination study of fresh seeds with pretreatments, maximum percentage of sound seeds that did not germinate after the completion of germination was 33.33% when seeds were sown after pretreatment. The maximum viability percentage recorded was 87.5%. Highest Peak Value (PV) was observed in the germination result of seeds pretreated with 100 ppm gibberellin for 20 minutes and sown in PBCP and the lowest Peak Value obtained was 0.17, when seeds sown after treatment with cold water, hot water and untreated seeds. Maximum value for Final MDG recorded after pretreatment with 100 ppm gibberellin and sown in RTPM and the minimum was 0.3, when seeds were sown after pretreatment with cold water. Maximum Germination Value was 0.8178 for seeds sown in root trainers with coir pith after treatment with hot water (Table 2).

3.4. Effect in Germination of Stored Seeds Using Different Sowing Media

Germination study of stored seeds show maximum viability percentage obtained was 58.33% when seeds sown after two and three months of storage. Highest Peak Value (PV) was observed in the germination result of seeds sown after one month of storage in GT and the lowest Peak Value obtained was 0.19 when sown in NB after two months of storage. Maximum value for Final MDG was obtained when seeds stored for one month were germinated in RTCP. Maximum Germination Value was, 0.493 for seeds germinated in PBPM after two month of storage (Table 3).

3.5. Analysis of Variance for Comparing Germination Percentage of Fresh Seeds

The results of ANOVA for comparing germination percentage with out pretreatment show significance at 1% level between medium of seed sowing and non significant between years of study and place of collection (Table 4). Maximum mean germination was obtained when seeds were sown in RTCP (48.61^a) and PBCP (47.92^a). The mean germination of seed samples collected from the two places (P1 36.57^a and P2 36.80^a) and between years of

study (Y1 36.11^a, Y2 37.85^a, Y3 36.11^a) shows homogeneity in mean germination percentage.

3.6. Analysis of Variance for Comparing Germination Percentage of Pretreated Seeds

Among the six types of pre-treatments and sowing medium used, the F-value shows significance at 1% level from the results showing analysis of variance found in Table 5. The mean germination under different medium and its comparison show homogenous results between the six media used in the present study. The maximum germination after treatment was observed when treated with hot water (54.17^a) and minimum value of (22.22^c) when seed coats were removed.

3.7. Analysis of Variance for Comparing Germination Percentage of Stored Seeds

It is obvious from the of ANOVA table for comparing germination percentage of stored seeds that there is significance at 1% level between media of study (Table 6). Maximum mean germination was (48.60^a) when three months stored seeds were sown in RTCP and the minimum mean percentage was recorded when seeds were sown in GT (20.83^e). It is obvious from the results (M1 38.89^a, M2 39.58^a, M3 38.19^a) that mean germination percentage has no decrease and remains homogenous even after three months of storage.

4. Discussion

For the germination studies of the Terminalia arjuna, the analysis of variance for comparing germination percentage of fresh seeds in different sowing medium show that there is no significance between the two collection points within the Kerala state in the present study (Table 4). Comparing the results in analysis of variance it is shown that the values are homogenous as mean germination of seed samples collected from the two places (P1 36.57^a and P2 36.80^a) and between years of study (Y1 36.11^a, Y2 37.85^a, Y3 36.11^a) shows homogeneity in mean germination percentage.

Comparing the results in analysis of variance for comparing germination percentage in show differences in mean germination due to different pretreatments. Seeds of T. arjuna have maximum germination performance with hot water treatment. Pretreatment with soaking seeds in concentrated H₂SO₄ results better germination but cold water treatment and seed coat removal have least effect. Concentrated sulphuric acid can consequently desiccate tissues and eventually cause cell separation [6] [7] but in the present study as the fruits has hard and woody fruit wall the germination percent has found to be increased.

Homogenous values were observed after the first, second and third month of storage but mean percentage is

^**Significant at 1 % level; ^*Significant at 5% level; ns: non significant at 5% level.

^**Significant at 1% level; ^*Significant at 5% level; ns: non significant at 5% level.

^**Significant at 1% level; ^*significant at 5% level; ns non significant at 5% level.

^*Corresponding author.

From the results of ANOVA for comparing germination percentage of stored seeds (Table 6) it is observed that there is significance at 1% level between sowing media and the mean germination percentages shows homogenous values in all the media except in germination tray.

Root trainers used in forest nurseries have been found effective as they have ridges of the specified type (antispiralling rib design) which force the developing roots to grow downward to the drainage hole, where they stop growing because of low humidity and air pruning effect which is effective when they are placed above the soil surface with the help of stand. The growth and survival of an out planted tree seedling is much related to the ability of its root system to promote regeneration of new roots, known as root growth potential (RGP) and its growth into the surrounding soil [10] [11] . For raising seedlings of tree species in plant nurseries, polythene bags of different gauges and size are the most common form of containers used widely. Even though, they are handy and economical they have inherent problem of root coiling which influences considerably the growth of seedlings after out planting in the field as the spiral roots prevent the seedling from becoming properly established in the surrounding soil [12] , and eventually leading to strangulation [13] . Although it can occur in any container type, root spiraling is most prominent in round and smooth walled plastic containers. To overcome the problem of root coiling in seedlings at least partially, the alteration of design in containers with vertically oriented ridges, ribs or grooves that protrude into the growing medium and present an obstacle to spiral and [14] recommended ribs about 2 mm (0.08 inch) high on the inner cavity wall. The root trainer technique developed may be useful in mechanized nurseries for mass production of seedlings in future plantation programs.

5. Conclusion

The technology developed through the present study is purely a reproducible one. A cultivator without adequate experience in the field can follow this technology and can produce any number of propagules to his desire. The tree species selected for the present study Terminalia arjuna is a well known tree species in indigenous medicine. Besides they are also suitable as avenue trees especially in the tropical area. Seed availability of the selected tree species is seasonal hence the optimum time to harvest fruits is during peak fruit ripening period. Seeds of Terminalia arjuna were gathered from two places of central Kerala and their germination studies were conducted in six different sowing media using fresh, pretreated and seeds stored up to three months. Germination value (GV) for all the field trials was calculated that showed highest for fresh seeds without pretreatments sown in PBCP and RTCP. Maximum GV for pretreated seeds were recorded in control and in gibberellin 100 ppm treated seeds sown in PBCP and RTCP. Application of hot water is recommended as pretreatment for the species and seed coat removal also favors germination. It is noted that Terminalia arjuna does not drop its germination percentage even after storage for three months. Analysis of variance shows significance at 1% level between medium, between pretreatments and between years of study. Transplantation shock, bulkiness, and frequent change of polythene bags cause additional labor by conventional method but root trainers have advantages such as requiring no change of medium.

Acknowledgements

The authors expresses their heartfelt gratitude to Dr. Thomas Philip, (Principal) Prof. P. J. Aleyamma and Dr. Thara K. Simon Head of the Botany Department, Union Christian College, Aluva, for providing space to conduct field trials in the Dr. T.C Joseph Memorial Botanical Garden, Department of Botany, Union Christian College, Aluva. Thanks to Mr. Thomachen, Gardener, Dr. T.C Joseph Memorial Botanical Garden, Department of Botany, Union Christian College, Aluva, for maintaining the field specimens throughout the study period. Extending a word of thanks to Mr. Jabir who helped in statistical correlation.

Cite this paper

Justin R. Nayagam,K. I. Mani Varghese, (2015) Germination Pattern and Root Trainer Performance of Terminalia arjuna: A Troublesome Tree Species in Plantation Trials. Open Access Library Journal,02,1-9. doi: 10.4236/oalib.1102167

References

NOTES

^*Corresponding author.