Nitrogen Nutrition of Greenhouse Pepper. I. Effects of Nitrogen Concentration and NO3: NH4 Ratio on Yield, Fruit Shape, and the Incidence of Blossom-end Rot in Relation to Plant Mineral Composition

Summary

Blossom-end rot (BER) is one of the major physiological disorders of green-house bell pepper (Capsicum annuum L.). The objective of the present work was to study the effects of the solution N concentration and N-NO 3: N-NH 4 ratio on fruit yield and the incidence of BER and other fruit-quality traits of greenhouse-grown bell pepper in a Mediterranean climate. Three experiments were conducted: Expt. 1 included five total N concentrations (0.25 to 14 mmol·L -1, with a constant N-NO 3: N-NH 4 ratio of 4); Expt. 2 included five treatments of different NO 3: NH 4 molar ratios (0.25 to 4, with a constant N concentration of 7 mmol·L -1); and Expt. 3 included three treatments of different NO 3: NH 4 molar ratios (1.0, 3.0 and 9.0, with a constant N concentration of 7 mmol·L -1). Plants were grown