Breaking Barriers: How Seed Coat Removal Boosts Terminalia superba Germination | InformativeBD

Joseph M Asomaning, from the institute of Ghana. Padmore B Ansah, from the institute of Ghana and Naomi A Fosu, from the institute of Ghana. wrote a Research article about, Breaking Barriers: How Seed Coat Removal Boosts Terminalia superba Germination. Entitled, The effect of seed coat removal on seed germination of Terminalia superba Engl. & Diels. This research paper published by the Journalof Biodiversity and Environmental Sciences | JBES. an open access scholarly research journal on Biodiversity. under the affiliation of the International Network For Natural Sciences| INNSpub. an open access multidisciplinary research journal publisher.

Abstract

The influence of four constant temperatures: 20°C, 25°C, 30°C, 35°C and three germination media: 1% water agar, heat sterilized river sand and seed testing paper (STP) on the germination of decoated seeds of Terminalia superba Engl. & Diels. were investigated. The germination media were placed in 90 mm diameter plastic Petri dishes with seventy five decoated seeds in 3 replicates of 25 seeds. The statistical design used in the investigation was a completely randomized design in a 3 x 4 factorial (germination media × incubation temperatures). Decoated seeds of T. superba germinated at all the four temperatures investigated. The optimum temperatures were determined as 25°C, 30°C and 35°C. All the three media can be considered ideal for the reason that these temperatures interacted with the germination media to record germination percentages ranging from 73 to 89% in the study. Mean germination time (MGT) was significantly (p < 0.001) shorter when agar was used as germination media compared to when germination was carried out on STP and soil. The shapes of germination curves describing the cumulative germination of decoated seeds of T. superba at all temperatures and on all the germination media investigated are S-shaped.

Read more :  Hidden Parasites:Trematode Larvae Diversity in Freshwater Snails of Burkina Faso | InformativeBD 

Introduction

Seed germination is controlled by several environmental factors, such as seed moisture content, temperature, and light. Seed condition also affects germination; for example, the seed coat may be water impermeable, or the mature seed may contain an underdeveloped embryo that only grows to full size after imbibition (Geneve, 2003). The seed coat represents a first line of defense against adverse external factors (helps protect the embryo from mechanical injury and from drying out) and also acts as channel for transmitting environmental cues to the interior of the seed (Radchuk and Borisjuk, 2014). Integrity of seed coat surface is extremely important for seed quality and fitness during seed storage or germination, and diverse technologies are available for preserving and enhancing of seed surface (Black and Halmer, 2006; Brooker et al., 2007).

That notwithstanding, an impermeable seed or fruit coat may impose physical dormancy which must be broken before water and air can reach the embryo and initiate germination (Baskin and Baskin, 2014). Most species have a seed coat which is impervious to water. This causes seed dormancy so that germination may extend over months or years. Example are the acacias and hence for their efficient germination at the nursery, it is necessary to apply some form of presowing treatment to ensure not only a high final germination percentage but rapid and uniform germination (Doran et al., 1983). The seeds of Prunus yedoensis also have slow and poor germination when intact. Decoating their seeds shortens the mean germination time (MGT) and improves seed germination percentage significantly. (Hyun Kim, 2019). Decoated seeds of Syzygium cumini germinated faster than coated seeds under nursery conditions, with high significant germination percentages, dry matter production rates and vigor indices (Sivasubramaniam and Selvarani, 2012).

Saeed and Thanos (2006) found seed coat to be inhibitory to the germination of Pinus gerardiana as removal of seed coat promoted both rate and final germination. Chika et al., 2020 reported that decoating seeds of Mansonia altissima improved their germination and resulted in the highest germination percentage. Bedada et al. (2018) also reported that de-coating improved germination and early nursery performance of Olea europaea.

Terminalia superba is one of the most heavily exploited African timber species, and locally, supplies have dwindled, with reports of declining populations in Côte d’Ivoire, Ghana, Nigeria, Cameroon and Congo (FAO,1984; N’Sosso, 1990). In Ghana, T. superba was one of the priority species earmarked for planting during the National Forest Plantation Development Programme launched in the year 2002. It is also on the list of priority species being planted under the on-going Ghana Forest Investment Programme. These developments have resulted in the need for sufficient quantities of good quality seeds to meet planting targets.

Cobbinah et al. (2001) and NTSC (2008) have reported days to first germination as 16 and 23 days respectively for seeds of T. superba sown intact. Unlike T. ivorensis, no serious dormancy problem has been reported about T. superba. However, pretreatment methods such as nicking or soaking in water have been recommended for faster and even germination (TTSA, 2010).

This study investigated the response of decoated seeds (seed with testa or seed coat removed) of T. superba to different temperatures and various germination media.

Reference

Asomaning JM, Sacande M, Olympio NS. 2011. Germination responses of Terminalia superba Engl. and Diels Seeds on the 2-Way Grant’s Thermogradient Plate. Research Journal of Seed Science 4(1), 28-39.

Asomaning JM. 2009. Seed desiccation tolerance and germination of seven important forest tree species in Ghana. PhD thesis. Kwame Nkrumah University of Science and Technology (KNUST), Kumasi, Ghana. 1-187.

Association of Official Seed Analysts (AOSA). 1992. Rules for Testing Seeds. Journal of Seed Technology 6, 1-125.

Bahuguna VK, Rawat MMS, Joshi SR, Maithani GP. 1987. Studies on the viability, germination and longevity of Terminalia myriocarpa seed. Journal of Tropical Forestry 3(4), 318-323.

Baskin CC, Baskin JM. 2014. Seeds: In Ecology, Biogeography, and Evolution of Dormancy and Germination (second ed.), Academic Press, San Diego.

Bedada AB, Amsalu T, Ayele B. 2018. Effect of different seed treatments, provenance and size on germination and early establishment of Olea europaea. African Journal of Agricultural Research 13(40), 2163-2172.

Black MH, Halmer P. 2006. The Encyclopedia of Seeds: Science, Technology and Uses. Wallingford: CABI

Brooker NL, Lagalle CD, Zlatani A, Javni I, Petrovic Z. 2007. Soypolyol formulations as novel seed treatments for the management of soil-borne diseases of soybean. Communication. Agric. Appl. Biol. Sci 72, 35-43.

Chika PJ, Sakpere AM, Akinropo MS. 2020. Effect of pretreatments on germination of seeds of the timber plant, Terminalia ivorensis and Mansonia altissima (A. Chev.). Notulae Scientia Biologicae 12(2), 334-340

Cobbinah JR, Siaw DEKA, Gyimah A. 2001. Guide to tree planting in Ghana. Forestry Research Institute of Ghana 1-33.

Daws ML, Gaméné SC, Sacandé M, Pritchard HW, Groot PCG, Hoekstra F. 2004. Desiccation and storage of Lannea microcarpa seeds from Burkina Faso, pp 32-39. In:. Sacande M, Joker D. Dulloo ME, Thomsen K (eds). Comparative Storage Biology of Tropical Tree Seeds. IPGRI, Rome, 363 pp.

Doran JC, Turnbull JW, Boland DJ, Gunn BV. 1983. Handbook on seeds of dry-zone acacias: A guide for collecting, extracting, cleaning, and storing the seed and for treatment to promote germination of dry-zone acacias. Division of Forest Research, CSIRO, Canberra, AUSTRALIA.

Ellis RH, Roberts EH. 1981. The quantification of aging and survival in orthodox seeds. Seed Science and Technology 9, 373-409.

Food and Agriculture Organization (FAO). 1984. Report of the Fifth Session of FAO Panel of Experts on Forest Gene Resources. FAO, Rome.

Geneve RL. 2003. Impact of temperature on seed dormancy,” Hort Science 38(3), 336–341.

HyunKim D. 2019. Practical methods for rapid seed germination from seed coat- imposed dormancy of Prunus yedoensis. Scientia Horticulturae 243(3), 451-456.

International Seed Testing Association (ISTA). 1999. International rules for seed testing. ISTA, Zurich, Switzerland 1-133.

Masetto TE, Faria JM, Fraiz ACR. 2014. Re-induction of desiccation tolerance after germination of Cedrela fissilis Vell. Seeds. Annals of the Brazilian Academy of Sciences 86(3), 1273-1285

N’Sosso D. 1990. Le statut de conservation des bois tropicaux commercialisables. Rapport National Du Congo. ITTO Pre-Project

NTSC. 2008. Tree Seed Catalogue. The National Tree Seed Centre, Uganda 1-51.

Palazzo AJ, Brar GS. 1997. The effect of temperature on germination of eleven Festuca cultivars. Special Report 97-19. US Army Corps of Engineers. CRREL Technical Publications.

Radchuk V, Borisjuk L. 2014. Physical, metabolic and developmental functions of the seed coat. Frontiers in plant science 5, p.510.

Saeed M, Thanos CA. 2006. The effect of seed coat removal on seed germination of Pinus gerardiana Wallich ex D. Don. Chilgoza pine. Journal of Applied & Emerging Sciences 1(3), 174-177.

Shafii B, Price WJ. 2001. Estimation of cardinal temperatures in germination data analysis. Journal of Agricultural Biological and Environmental Statistics 6, 356-366

Silveira FAO, Fernandes GW. 2006. Effect of light, temperature and scarification on the germination of Mimosa foliolasa (Leguminasae) seeds. Seed Science and Technology 34, 585-592.

Sivasubramaniam K, Selvarani K. 2012. Viability and vigour of jamun (Syzygium cumini) seeds. Brazilian Journal of Botany 35(4), 397-400.

Tanzanian Tree Seed Agency (TTSA). 2010. Seed Catalogue. Tanzania Tree Seed Agency. 1-26.

Article source : The effect of seed coat removal on seed germination of Terminalia superba Engl. & Diels