European Journal of Horticultural Science

Eur.J.Hortic.Sci. 83 (5) 319-328 | DOI: 10.17660/eJHS.2018/83.5.5
ISSN 1611-4426 print and 1611-4434 online | © ISHS 2018 | European Journal of Horticultural Science | Original article

Impacts of genetic material and current technologies on product quality of selected greenhouse vegetables ─ A review

N. Gruda¹, D. Savvas², G. Colla³ and Y. Rouphael⁴
¹Division of Horticultural Sciences, Institute of Plant Sciences and Resource Conservation, University of Bonn, Bonn, Germany
²Laboratory of Vegetable Production, Agricultural University of Athens, Athens, Greece
³Department of Agricultural and Forestry Sciences, University of Tuscia, Viterbo, Italy
⁴Department of Agricultural Sciences, University of Naples Federico II, Portici, Italy

SUMMARY
Product quality is a multi-factorial issue that depends on both pre- and post-harvest factors. Most studies on vegetables consider, however, the influence of postharvest and/or processing factors. Good post-harvest and processing conditions can only retain quality characteristics defined by pre-harvest factors. In addition, greenhouse vegetables are used by consumers as fresh products that are not processed. Thus, it is imperative to maximize quality of greenhouse vegetables through appropriate pre-harvest growing techniques. Here we review the impacts of genetic material and new efficient cultivation technologies and practices on product quality of greenhouse vegetables, referring to studies carried out from the beginning of this century. The major points are the following: (i) due to adapted growing conditions greenhouses provide not only high-value vegetables, high yields, extended cultivation time and earliness but they are also a good tool to improve product quality; (ii) higher quality can be obtained by specific agronomic techniques, such as, e.g., moderate plant stress, adequate plant space and other cultural management; however, these are not to be considered separately but as part of an overarching system. Since product quality does not always correlate with high vegetable yields and vice versa, sometimes compromises need to be made.
Keywords cultural management, growing techniques, harvest time, mineral nutrition, pre-harvest factors, protected cultivation, salinity, soilless culture
Significance of this study
What is already known on this subject?

Product quality has been gaining interest in recent horticulture. Product quality and the level of healthy important compounds vary according to plant genetic composition of species and cultivars used, environmental conditions, and developmental stage. However, the effect of growing techniques and cultural practices on product quality have been little studied in greenhouse vegetables.
What are the new findings?

Several relations, as well as interactions, between genetic composition, fertilizer, and biotechnological applications on one hand and different quality attributes and healthy important compounds, such as contents of nitrate, vitamins and secondary metabolites on the other hand are new and important findings both for the producer and consumer.
What is the expected impact on horticulture?

The overall impact of this review could be of interest for all actors dealing with product quality and “healthy horticultural produce” and interested in interactions between growing techniques, cultural practices and content of different compounds and metabolites in greenhouse vegetables.

E-mail: ngruda@uni-bonn

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Received: 17 October 2017 | Accepted: 18 May 2018 | Published: 12 November 2018 | Available online: 12 November 2018