Seasonal Effect on Growth Parameters and Macronutrient Use of Sweet Pepper

ABSTRACT

Sweet pepper plants (Capsicum annuum L.) grown under greenhouse conditions differed widely in the rate of production of their total dry mass and their harvestable weight, although there was not shortage in water or nutrient supply. Plants were grown in aerated nutrient solutions along two different growing seasons. The differences in plant productivity were mainly due to the environmental conditions of the growth cycle. During the increasing day length season, from the beginning of spring to summer (13.0 to 14.8 h day^{− 1}), plants produced the largest amount of fruits, but with a 10% blossom-end rot incidence. In the season of short photoperiod, progressing from the beginning of autumn to winter with 13.3 to 10.3 light h day^{− 1}, the total dry weight and yields gradually decreased, but blossom-end rot in fruit did not appear. Different growth patterns were found for morphological and physiological parameters, because of the different light loads received by the canopy, being adjusted to the seasonal variables. Reduced light load markedly reduced leaf area and leaf thickness, but increased specific leaf area, which gave plants an increased ability to intercept light. Not only the amount of initial biomass, but radiation and the age of the pepper plants were the main growing driving factors, influencing relative growth rate, nitrogen (N)-use efficiency, and calcium (Ca) partitioning. Moreover, mathematical approaches for prediction of biomass production and N accumulation as a function of radiation are given in order to establish in the future a sweet pepper growth model.

Keywords:

• blossom-end rot
• Capsicum annuum L
• growth parameters
• leaf development
• light load
• N-use efficiency

ACKNOWLEDGMENTS

This project is carried out with the financial support of the European Commission under the RTD program “Quality of life and management of living resources” (project QLTR-1999–31301). It does not necessarily reflect the Commission's views and in no way anticipates its future policy in this area. The authors are grateful to De Ruiter Seeds-Hybrid Seeds for supplying the seeds and to C. Serrano, C. Cano, E. Blanco and E. Bueno for their technical support in plant analysis.