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

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.