Clarity in recording Germination Data

Abstract

TIMSON¹ suggests that, compared with straight germination percentages, the following procedure would provide a more meaningful evaluation of germination data: the total percentage of seeds which have germinated to date is recorded every day for a stated number of days from sowing, and these daily values are summed. Timson terms the result thus obtained from observations up to, for example, day 10, the ‘Σ10’. This scheme is possibly as successful an attempt as any at producing a unified expression of two values, germination percentage and time to germination. But any such expression is apt to obscure, rather than clarify, the situation, except when germination is both rapid and high or both slow and low. For example, with two hypothetical seed samples the percentages germinating on successive days may be 40, 20, 0, 0, 0 of sample A, and 10, 30, 30, 30, 0 of sample B. Timson's Σ4 would therefore be 40 + 60 + 60 + 60 = 220 for A, and 10 + 40 + 70 + 100 = 220 for B, although the two samples are dissimilar in both germination percentage and time to ultimate germination. More-over, a shorter period of assessment would favour the faster, a longer period the more fully germinating sample: Σ3 would be 160 for A and 120 for B, whereas Σ5 would be 280 for A and 320 for B.