A specified test for germination, recording the endpoint, conditions and observation window. For a proposed red/far-red light test, use randomization to allocate one seed lot to darkness, red, red then far-red, and red then far-red then red. Match hydration, temperature, handling and elapsed time before counting; use sham waiting periods to equalize schedules. Use dish replication, retain the dark scientific control, and record radicle emergence using an observation procedure that does not itself provide an uncontrolled light treatment. This is a proposed design, not a claim about the 1952 paper's randomization or replication.
As an original hypothetical counting example, begin with seeds in one dish. Suppose 12 first meet the radicle endpoint by 24 hours, eight additional seeds by 48 hours, and four additional seeds by 72 hours. These invented event counts giveand cumulative sample proportions , and . The 48-hour increment is , not ; the latter includes earlier events. Counting the same emerged radicle again at each inspection would inflate the total. These numbers illustrate bookkeeping, not biological rates or treatment effects.
With a fixed denominator and irreversible classification of the first endpoint event, the set counted at an earlier inspection is a subset of the set counted later. Hence and cannot decrease. This short proof applies to cumulative germination counts even if a later seedling dies. A count of currently surviving seedlings has a different definition and can decrease.
For treatment comparisons, the dish may be the experimental unit: seeds in the same dish share conditions. Forty seeds in one dish do not supply forty independent dish replicates. Report the sample size, replication, endpoint time and denominator; a sample proportion by a deadline measures this assay's outcome, not an unconditional fraction with seed viability.
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