Thresholds of Initiation

In bright light the acid number increases rapidly. The threshold of initial phytotoxicity (0.16) is reached in approximately 80 days. In diffuse light initial visible injury does not occur until near the end of a storage period of 325 days, at which time an acid number of approximately 0.16 has been reached. Material stored in the dark reached an acid number of 0.08 in 325 days and, at this time, caused no injury to beans or com. If we may assume the same continuing rate of increase in acid number, the material stored in the absence of light will not reach the phytotoxic threshold point of 0.16 until it has been stored for approximately 450 days. 

See J.L.Henderson, Thresholds of Initiation, Middletown, CT, Wesleyan University Press, 1967. 

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