Which one of the following pair is mismatched

Answer: Option D

L-value was first suggested by Larsen in 1952. L-value also known as ‘Labile form’ is the amount of phosphorus in the soil and in the soil solution which is exchangeable with added orthophosphate to the soil as measured by a plant growing in the system.

Colwell in 1967 emphasized the importance of soil testing through an integrated soil test approach to crop yield response to provide information on fertilizer requirements.

Desai and Biswas in India first demonstrated the production of combustible gas from cow dung i.e. Biogas by anaerobic fermentation in 1975.

The Law of limiting factors is given by Blackmann, not Lundegardh.