Evidence on declining fruit and vegetable nutrient composition
[In 1981] Jarrell and Beverly found that fertilized plants contained larger absolute amounts of minerals than the unfertilized plants, but these amounts were sufficiently diluted by the increased dry matter that all mineral concentrations declined, except for phosphorus, which is the common fertilizer.
… plantings of low- and high-yield cultivars of broccoli and grains found consistently negative correlations between yield and concentrations of minerals and protein, a newly recognized genetic dilution effect.
(via kottke)
