The law of limiting factors for photoshythesis was enunciated by

The law of limiting factors for photosynthesis was enunciated by Blackman.
In 1905 Frederick Blackman articulated the role of limiting factors as follows: "When a process is conditioned as to its rapidity by several separate factors the rate of the process is limited by the pace of the slowest factor."
The identification of a factor as limiting is possible only in distinction to one or more other factors that are non-limiting.