Th e Ph ot os yn Ryley Rachel

Th e Ph ot os yn Ryley, Rachel, Jacob, and Mitchell th e siz er s

Question Will different wind speeds affect percent germination of pea seeds?

Hypothesis If the fan is on high setting (1. 7 m/sec), then the germination percent will be lower.

Materials 12 petri dishes 3 fans 60 pea seeds Shoe box Distilled water Graduated cylinder

Procedure 1. Obtain 60 pea seeds and 12 petri dishes 4. Repeat Step 3 with the labels: no wind, low wind, and medium wind. 2. Place 5 seeds in each dish and add 12 m. L of distilled water. Do not 3. Label 3 petri cover. dishes as follows: High 1, High 2, High 3. 5. Obtain 3 fans. Measure all 3 fans’ wind speed settings on low. Record. 6. Repeat step 5 for the medium and high settings.

Procedure Continued 7. Determine which fan to use with which setting by using the fan with the lowest speed for the “low wind” dishes, fan with the highest speed for the “high wind” dishes, and the last fan available for the medium speed. 8. Place dishes labeled “no wind” in open-topped shoe box. Set off to the side away from the fans, but in equal light.

Procedure Continued 9. Set up the fans by placing them far enough away so they won’t interfere with other fans. 10. If needed, use a stool or a box to give the petri dishes enough elevation to be placed directly under the wind. 11. Place petri dish next to corresponding fan. 12. At the beginning of the school day the following day, turn on all the fans to the appropriate speed. Turn off after 7 th hour.

Procedure Continued 13. Water peas each day with 5 m. L of distilled water. 14. Repeat step 10 each day for 10 days until germination occurs. Note: germination in this experiment is the appearance of the hypocotyl. 15. Record percent germination each day and note any other changes in the data table.

Measuring Wind Speed An app from the Google Play Store, called Zephyrus Windmeter was used to measure the wind speed in this experiment The phone was placed in front of the fan, equidistant from where the petri dishes would be placed. The fans were turned on, and the wind speed was measured in meters per second.

Variables Humidity Am oun thro t of ligh ugh out ting the da y e h e t m i t f o t n u o n o Am e r e w s n fa ld o M

Qualitative Data Day 1: None of the seeds have shown signs of germination. We however noticed right away that the fans tend to dry the seeds out quite quickly, and we will for sure have to add water to each petri dish every day. Day 2: The “high wind” seeds are very dry. The “No Wind” seeds look very healthy and on the right track to germinating soon. They are a bright green color while the low, medium, and high settings were a dull green and look dried out. However, one seed on the medium setting is starting to show signs of germination. Day 3: Many seeds are starting to show germination.

Qualitative Data continued Day 4: One of the seeds in the “high” dish has become so dry that it has split in half. Day 7: No Wind 1 and Low Wind 2 has developed mold. Day 8: The seeds are as germinated as they are going to get. One of the seeds in Medium Wind 2 has completely lost its seed coat.

Percent Germination

Graph NW= No Wind, LW= Low Wind, MW= Medium Wind, HW= High Wind

Who uses this info? Farmers Scientists Botanists Science teachers Agronomists

Conclusion We predicted the seeds in the high setting would have a lower germination rate than the rest of the seeds. Our conclusion did not support our hypothesis. The Medium setting had the highest average germination percent at 60%, the No Wind and High settings were equal at 40%, and the Low Wind had the lowest average germination at 20%. Hence, our hypothesis was not supported.

Further Questions Would this experiment turn out different if we had used soil? Would things be different if we had used bean seeds? Would different water amounts affect germination?