The Germination of Seeds of the Native Plant Acacia decurrens Practical Report Biology 1 Introduction: In a botanical sense, “germination is the process of emergence of growth from a resting stage. ” (http://encyclopedia. laborlawtalk. com/germination). Under favourable conditions, the seed begins to germinate, and the embryonic tissues resume growth, developing towards a seedling. Soils from a Cumberland Plain Woodland community were investigated to determine the presence of a soil seed-bank; and whether species richness and abundance of plants germinating from it were affected by heating such as that experienced in a fire.
It was found that certain seeds reacted differently, and he the phsyical action of heating, whether at low or high temperatures affected the rate at which the seeds germinated. (Hill & French 2003). Acacia seeds will not usually germinate without the use of a pre-treatment. As they have a hard outside coating which is generally impermeable to water. For Many Acacia seeds the breaking of the dormancy occurs with heat and although smoke and ash stimulate seed germination for many species with hard coats, heat is the main factor influencing the germination of Acacia decurrens.
In the natural environment, the hard coating of the Acacia seeds may be broken down due to a bush fire allowing the plant to begin rejuvenation (Hill & French 2003). The intention for this experiment was to determine whether the effects of heat increased or decreased the rate at which Acacia decurrens germinated. The hypothesis to be tested is; “If the Acacia decurren seeds are exposed to heat, then the rate at which they germinate will be increased. ” Hypothesis: If the Acacia decurren seeds are exposed to heat, then the rate at which they germinate will be increased.
Experimental Design and Method: The main utensils used in this experiment were the assortment of 60 Acacia decurrens seeds, cotton wool and 2 petri dishes, which were all supplied by the university. The seeds appeared to be a random sample, differing in shape, size and form. The decision to randomly select and divide the seeds into four groups of 15 was made. These 4 seed groups were placed into the four separate petri dishes and were titled Heated 1 & 2, and Control 1& 2.
In order to determine the effects of heat, the experiment needed a control group of non heat treated seeds, and also for the experiment to be duplicated to observe whether it was through the purposeful actions which the seeds were subjected to that may cause germination or whether external or uncontrollable factors also caused the seeds to germinated. Therefore of the four seed groups, both Heated 1 & 2 would be subjected to heat treatment process and the Control groups would be used as a standard by which to compare experimental observations.
The Heated 1 & 2 groups of seeds were placed into beakers, and had potable boiling water poured over them. They were then left submersed in this water [which eventually cooled to room temperature] for a period of 24hrs. The remaining 2 Control groups of seeds, were soaked the in same way but soaked in cold water and again left for 24hrs. All four beakers were filled so that the seeds were fully immersed and covered over by the water.
After 24 hours, each group of seeds were placed into 4 separate Petri dishes. Each Petri dish was covered in a layer of cotton wool, which was moistened with potable water. This moistening of the cotton wool pieces was repeated numerous times daily or whenever wool piece was seen to become dry. The Petri dishes were labelled: Heated 1, Heated 2, Control 1 and Control 2. The seeds were checked once daily for 10 days to take specific note of germination progress, or of any change in physical appearance.
Daily observations were recorded in a diary and then placed into a table of results featured below. Results: Effects of heat on Acacia Decurrens | No. Germinated| No. did notGerminate| First sign ofGermination| % seeds thatGerminated | Heated 1| 9| 6| Approx. 96hrs| 60%| Heated 2| 11| 4| Approx. 72hrs| 73%| Control 1| 0| 15| 0| 0| Control 2| 0| 15| 0| 0| Both Heat treated groups 1 & 2 had seeds that germinated within 3-4 days of receiving this heat treatment. This averaged the amount of 66. % of the total seeds germinated. In contrast both Control groups that were not subjected to any form of heat treatment but were still soaked in cold water did not show signs of germination at all within the 10 days time limit. Discussion: The results of the experiment demonstrate that if Acacia decurrens seeds are subjected to the heat treatment by placing the seeds in boiling water and leaving them in that same water for a period of 24 hours, then the rate at which the seeds germinate will be affected.
It can be suggested that this increased germination rate occurs because the boiling water, by which the seeds were soaked in, breaks down the hard coating on the outside layer of the seed, thus allowing the seedling to penetrate through the coating and begin the germination process. This controlled experiment is a simulated example of what might happen during a bushfire, when after the fire is put out most of the vegetation begins to rejuvenate due to the fact that the heat from the fire it self, has increased the rate at which certain seeds including the Acacia Decurrens germinate.
Furthermore, for a more scrupulous analysis of this subject, the experiment performed ideally should be repeated a number of times which include a higher variety of climatic conditions. This would allow for further investigation into the exacting factors and specific limits which affect the seed germination process. Moreover, the time span in which the seeds are observed should also be increased. These differing aspects would allow for a more accurate report and examination on the effects of heat treatment on the Acacia decurrens seeds.
Conclusion: Through the results collated it is evident that the hypothesis of; If the Acacia decurrens seeds are exposed to heat, then the rate at which they germinate will be increased, is in fact true. As mentioned above, the hard outer layer of the Acacia decurrens seed means that germination of this seed is difficult without the subjection to some form of heat. In this instance the heat source was from boiling water, but other heat treatments may also increase this germination rate. References: * Auld, T.
D. , O’Connell, M. A. (1991) Predicting patterns of post-fire germination in 35 eastern Australian Fabacaeae, Australian Journal of Ecology 16, 53-70 * Hill SJ ; French K (2003) Response of the soil seed-bank of Cumberland Plain Woodland to heating, Austral Ecology 28, 14-22(9) * Dictionary. Oxford Dictionary of Science Fourth ed (2003) Oxford University Press Inc. New York * Dictionary. Labour Law Talk (2005) Available at http://encyclopedia. laborlawtalk. com/germination (accessed 01/04/2008)
Why Work with Us
Top Quality and Well-Researched Papers
We always make sure that writers follow all your instructions precisely. You can choose your academic level: high school, college/university or professional, and we will assign a writer who has a respective degree.
Professional and Experienced Academic Writers
We have a team of professional writers with experience in academic and business writing. Many are native speakers and able to perform any task for which you need help.
Free Unlimited Revisions
If you think we missed something, send your order for a free revision. You have 10 days to submit the order for review after you have received the final document. You can do this yourself after logging into your personal account or by contacting our support.
Prompt Delivery and 100% Money-Back-Guarantee
All papers are always delivered on time. In case we need more time to master your paper, we may contact you regarding the deadline extension. In case you cannot provide us with more time, a 100% refund is guaranteed.
Original & Confidential
We use several writing tools checks to ensure that all documents you receive are free from plagiarism. Our editors carefully review all quotations in the text. We also promise maximum confidentiality in all of our services.
24/7 Customer Support
Our support agents are available 24 hours a day 7 days a week and committed to providing you with the best customer experience. Get in touch whenever you need any assistance.
Try it now!
How it works?
Follow these simple steps to get your paper done
Place your order
Fill in the order form and provide all details of your assignment.
Proceed with the payment
Choose the payment system that suits you most.
Receive the final file
Once your paper is ready, we will email it to you.
No need to work on your paper at night. Sleep tight, we will cover your back. We offer all kinds of writing services.
No matter what kind of academic paper you need and how urgent you need it, you are welcome to choose your academic level and the type of your paper at an affordable price. We take care of all your paper needs and give a 24/7 customer care support system.
Admission Essays & Business Writing Help
An admission essay is an essay or other written statement by a candidate, often a potential student enrolling in a college, university, or graduate school. You can be rest assurred that through our service we will write the best admission essay for you.
Our academic writers and editors make the necessary changes to your paper so that it is polished. We also format your document by correctly quoting the sources and creating reference lists in the formats APA, Harvard, MLA, Chicago / Turabian.
If you think your paper could be improved, you can request a review. In this case, your paper will be checked by the writer or assigned to an editor. You can use this option as many times as you see fit. This is free because we want you to be completely satisfied with the service offered.
Effortlessly get the essays and grades you need. You can now get any essay, on any subject and at ANY deadline with just 10 minutes of your time (or less). Your professor will love you for it!