NUTRIENT FILM TECHNIQUE: IRON NUTRITION OF SWEET PEPPER IN RELATION TO ROOT TEMPERATURE

A factorial experiment comprising 3 root temperatures (20, 25 and 30°C) and 4 iron III EDTA levels (3, 6, 12 and 18 ppmFe) examined plant growth and fruiting of sweet pepper.

Total aerial dry weight, root dry weight and fruit yield showed a similar response.
Iron and temperature treatments appeared to interact, with 3 ppmFe having a 30°C optimum whilst 18 ppmFe had a 20°C optimum.
There was a steady reduction in plant growth with increasing iron, which resulted in the 30°C/3 ppmFe treatment having the greatest ‘yield’. Root growth was the most seriously affected with all 18 ppm Fe treatments having few severely stunted roots.

Leaf analysis data suggest EDTA antagonism of micronutrient uptake, particularly copper, although the direct toxicity of EDTA cannot be ruled out.

Symposium on Substrates in Horticulture other than Soils In Situ

D.C. Cull

https://doi.org/10.17660/ActaHortic.1982.126.45