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Horticultural cultivation in Mediterranean greenhouses requires the implementation of refrigeration systems to avoid stress situations, particularly under spring-summer conditions. The effect of the temperature and high solar radiation in the greenhouse can be decreased by shade screen. The use of grafting onto adequate rootstocks could be an interesting alternative to maintain commercial fruit yield and quality under stress conditions. The effects of using aluminised screens offering different degrees of shading combined with two transplant types (grafted or ungrafted) were analyzed in sweet pepper plants. Simultaneous comparisons were made among greenhouse that were either non-shaded (control) or covered with reflective aluminized shadecloth that attenuated 40% (T40) and 60% (T60) of direct sunlight. The shadecloth was applied at the start of warm weather in May. The greenhouses were shaded for the rest of the summer, and fruit being picked until August. The use of shadecloth proved to be efficient in improving vegetative growth and reducing the unmarketable yield, compared to non-shaded conditions. The results showed that fruit yield was highest in the T40 treatment, presented significantly different, and the T60 treatment had a lower production. On the other hand the use of the grafting promoted vegetative growth. Grafting increased the marketable yield compared to the ungrafted plants under shade and non-shade conditions.

Removal and disposal of polyethylene mulch in vegetable production represents a high economic and environmental cost to society. A field experiment was performed with broccoli crop under Mediterranean conditions (Murcia, Spain) to evaluate the feasibility of substituting the currently used mulch materials. Black and transparent polyethylene (PE) mulch were compared with bare soil (control) and three biodegradable plastic mulch materials (MB green, MB black, MB transparent). Data loggers were installed 7 cm deep into the soil under various mulches to record soil temperature. The experiment used a randomized complete block design with four replications. Mulch degradation, soil temperature and broccoli growth and biomass were assessed. Plant growth, estimated as the total dry weight produced, was similar for MB and PE treatments. Results indicate that soil temperatures under the biodegradable mulches were similar to the PE mulch. All mulch treatments were successful for weed control. Mechanical analyses indicated that the MB had initially a lower resistance and elongation percentage at break point than PE.