b'in Murcia-Alicante (S-E- Spain) around the year 2000. GrowersAGRO-ECOLOGICAL APPROACHin that area experienced a much better pest control, and a sig- Until a few years ago, the overall concept of horticulture con-nificant increase in crop yield, thanks to the natural enemies. Insisted of crops grown in a sterile environment. Before each plant-the largest production area in Spain, Almera, large scale adoptioning, the greenhouse soil and structure were disinfected; weeds was finally achieved in 2007 (Graph 1).were carefully removed, and the immediate surroundings of the The introduction of biological control has had a major influ- greenhouses were kept free from vegetation out of fear that wild ence on the commercialisation of sweet pepper, as becomesplants might favour the propagation and distribution of pests clear from the export figures from Spain to Germany (Graphand diseases. With the introduction of biological control agents, 2). Due to excessive pesticide residues, export dropped over 40%live insects and mites that can be obtained commercially, this between 2004 and 2007. The implementation of IPM permittedconcept started to change. Currently, it is recognised that also a recovery of the export volume, and a spectacular growth aftermany spontaneously appearing insects and mites may have a 2012. After 2007, biological control was gradually also adoptedcrucial contribution in the control of important pests. in IPM systems in other crops. As a result of the major change inA typical example is the tomato leaf miner Tuta absoluta, pest management, products from the greenhouses in SE Spainthat has become resistant against the available insecticides and are now proudly presented, with residue levels that are far belowcauses major losses. The most effective natural enemy of T. the limits set by the most demanding clients. absoluta is a parasitoid that, until now, cannot be reared com-mercially. However, this little wasp, Necremnus tutae, appears GRAPH 2. EXPORT VOLUME OF SWEET PEPPERspontaneously in all crops and can completely control the pest FROM SPAIN TO GERMANY when the conditions are appropriate, as was documented in 200 many cases. These conditions include a minimum use of selected pesticides as well as certain environmental adaptations. Both inside the greenhouses and in the near surroundings, non-crop vegetation is planted, providing shelter and food sources to this and other beneficial fauna. In practice, many growers maintain flowering plants in 150 between the crop lines, from which parasitoids, like Necremnus EXPORT VOLUME (X1.000TM)tutae, can ingest nectar or pollen as a necessary source of energy. Around the greenhouses, more and more hedgerows of native plants and shrubs are planted, knowing that these will soon harbour a wide range of beneficial arthropod species and act as barrier for pest organisms. Biodiversity is now considered 100 a key element of sustainability, completely functional within the greenhouse horticultural system.ENVIRONMENTAL IMPROVEMENTSThe results of environmental improvements start to become visible in the greenhouse surroundings, for instance through the increased presence of birds and reptiles. Immediately next 50 to the horticultural areas, several protected wetlands harbour 2002 2003 200420052006 2007 20082009 2010 2011 2012 2013 2014 2015 2016 2017YEARa rich fauna, and supply breeding ground to some of the rarest aquatic birds of Europe. Many of these species, like gulls, terns and herons, forage in the ponds that are used as water reserves WASTE MANAGEMENT next to each greenhouse. But, perhaps the best indication of the Horticulture in the province of Almera generates large volumesimprovements is the presence of insectivorous birds and reptiles of residues that should be processed adequately. Logically, in aimmediately in and between the greenhouses. Several species of greenhouse covered landscape, the recycling of plastic residueslizards are now commonly present within the greenhouse crops. is calling attention, both by local organizations and by mediaEspecially well documented is the expansion of the chameleon in the countries of destination for export. Enormous progressin Almeria, of which there was always a small isolated popula-was made when the burning of residues was forbidden, and thetion in one specific area of the province. However, this species recollection became compulsory, about 20 years ago. At present,is now found all along the area and frequently even seen inside approximately 80% of the plastic is recycled, including all thethe greenhouses. material used for greenhouse covers. Growers generally replace the cover plastic every four years and get paid for the old plasticWELL ON ITS WAY since it is a homogeneous residue, perfectly fit for recycling. TheThe greenhouse sector consists of many thousands of inde-remaining 20% of waste, mostly consisting of thin plastic sheets,pendent growers who all have to contribute to make the horti-cans and bottles used for packages, etc., is usually incinerated.cultural system future proof. They must continuously change The recycling percentage of horticultural plastic is,their way of thinking and working and adopt new technologies undoubtedly, far higher than that of urban plastic waste.and insights. This is not just a technological process, but also However, in a concentrated greenhouse area, this can, andan enormous social challenge. Nevertheless, the sector has should, be improved, since it is perfectly possible to get to ademonstrated that it is able to make great steps if necessary. proper separation of different materials and to create the opti- Although there is still a lot to be done, greenhouse horticulture mal logistics. The growers and their organizations are very muchin Southern Spain is well on its way to sustainability.aware of the urgency of this task. As long as there is only a tiny fraction of abandoned plastic dumped in the environment, theEditors Note: Jan van der Blom is entomologist in the image of the region, and its commercial position, will remainDepartment of Production Techniques of COEXPHAL in extremely vulnerable. However, this requires some new tech- Almeria, Spain.nological solutions, as well as a certain level of discipline among the 15,000 growers and their workers in the region.42IEUROPEAN SEEDIEUROPEAN-SEED.COM'