Stress Effects on Seed Germination

Jon Hoch

Student of Conservation Biology

Tennessee Technological University

Project Summary

• Does stress affect seed germination and if so, relatively how much? With this experiment these topics will be discussed using varying forms of stress on seeds and recording the ratios of germinated seeds to dormant seeds to try and measure general tolerance levels for three common cultivars including corn, radish, and turnip. Anticipated results consist of having seeds in stressful conditions being less likely to germinate and more likely to remain in a dormant state.

Introduction

• This study deals with seed germination under abiotic stresses and how stress should restrict germination allowing the seed to remain dormant until improved conditions come about. The study will test the different seeds susceptibility to stress and give insight to their preferred germination conditions. Studies have been performed about factors affecting germination (Taiz & Zeiger 2002) and how plants deal with stresses (Bohnert et al. 2001). Studies have also shown that mild stress sometimes increases chances to germinate as in the case of seeds which must be scarified or chilled (Taiz & Zeiger 2002).

Methods and Materials

• Experimental protocol includes the use of a randomized block design in which seeds from the three cultivars are placed under stressful conditions and monitored for germination. Ten seeds are placed on filter paper, watered, and closed in a Petri dish to prevent contamination. All three cultivars are to be exposed to each stress condition and there will be four sub-samples of each species to increase statistical accuracy.

• The stress conditions include low light, heat stress at 45°C, salt stress at a 1mol NaCl solution level, and salt stress at a diluted 1/10th mol NaCl solution and their will also be a control group kept at room temperature with no added saline solution and on a regular light schedule .

Data Sheet

Control group Corn Radish Turnip Sub-sample 1: 1: 1: 2: 2: 2: 3: 3: 3: 4: 4: 4:

1mol NaCl solution Corn Radish Turnip Sub-sample 1: 1: 1: 2: 2: 2: 3: 3: 3: 4: 4: 4:

1/10th mol NaCl solution Corn Radish Turnip Sub-sample 1: 1: 1: 2: 2: 2: 3: 3: 3: 4: 4: 4:

Heated to 45ºC Corn Radish Turnip Sub-sample 1: 1: 1: 2: 2: 2: 3: 3: 3: 4: 4: 4:

Low light Corn Radish Turnip Sub-sample 1: 1: 1: 2: 2: 2: 3: 3: 3:

4: 4: 4:

Expected Results

• Expected Results include the lack of germination of seeds in the high saline solution and the seeds subjected to the heat stress. Also expected is a lower ratio of germinators in the low light and mild saline solution tests. There should be the highest ratio of germinators in the control group under the least amount of stress.

BudgetEquipment

50 100ml sterilized Petri dishes $12

Filter paper $ 3

Seeds $ 6

Salary

Technician $10

Total Expenses $31