Optimal pH Levels for Radish Seed Germination
Do radish seeds germinate best in neutral, acidic or alkaline solutions?
Germination is the reestablishment of metabolic processes in a seed after a period of dormancy. The germination process varies for different seed varieties. Generally, germination begins when water causes the outer covering of the seed to loosen. The uptake of water by the seed triggers the release of hormones needed for respiration, protein synthesis, and the activation and production of the digestive enzymes needed to hydrolyze the nutrients stored in the seed (Lockwood & Hartman, 2009). These nutrients are consumed as a seed 's embryotic cells elongate and increase in size to form a radicle (root) and plummule (first shoot). The emergence of a radicle from the seed case signals that germination is complete (Finkelstien & Lynch, 2000).
There are four main external factors that aid the germination process: water, oxygen, light, and temperature. Germination cannot occur in most mature seeds without water, which is essential in restoring the metabolic processes of dormant seeds. Under watering or overwatering can be detrimental to seed germination as well the pH level of the water. When a seed coat splits, seed respiration switches from anaerobic to aerobic (Lockwood & Hartman,…show more content… According to the University of Vermont extension professor, Leonard Perry, radish seeds thrive best in soil that have a pH range of 6.0 to 7.0, which falls in the neutral to slightly acidic range (Perry, 2003). The Ohio State University Extension states that radishes grow best in mineral soil with a pH of 6.0 to 6.8, but when planted in muck soil (fertilized with manure) a pH of 5.2 to 5.6 is preferred (Corrigan, ng). A slightly acidic pH was hypothesized because the seeds were not being tested in soil and a pH of 6.1 is mid range between 5.2 and