The Mediterranean fruit fly, Ceratitis capitata (Wied.), is an endemic pest in fruit-growing areas of the Spanish Mediterranean coast. In the Valencian Community, it represents a serious problem in the cultivation of citrus and numerous species of fruit, such as peach, cherry, apricot, persimmon, etc. For over 50 years, the Department of Agriculture of Valencia has led, promoted, and carried out a C. capitata control programme to protect crops, especially citrus fruits, because this community is the largest national producer and the leading region for fresh citrus exports in the world. Traditionally, pest control has been based on the use of insecticides. However, a reduction of more than 90% of a target wild population was achieved in the frame of a pilot integrated pest management (IPM) project based on the sterile insect technique (SIT), which was implemented from 2003 to 2006. Based on this successful result, in 2007 the Department of Agriculture of Valencia initiated an area-wide integrated pest management (AW-IPM) programme for the suppression of C. capitata, using the SIT as the primary control method. Complementary activities are implemented periodically in hotspots and during different time periods depending on the pest population dynamics. As a result, there has been a reduction of more than 90% in the use of insecticides by aerial means to control C. capitata, as well as a growth trend in exports of citrus and fresh fruits from the Valencian Community in recent years. This paper provides a historical review of the Valencian programme and briefly describes how technological innovations and decision-making tools have contributed to programme efficiency.

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Aedes albopictus and Aedes aegypti are the main vectors of arboviral diseases such as dengue, Zika and chikungunya viruses. About a third of the world population is currently at risk of contracting Aedes-borne epidemics. In recent years, Ae. albopictus has drastically increased its distribution in many countries. In the absence of efficient mosquito vector control methods, the sterile insect technique (SIT) is presented as a very promising and environment-friendly control tool. The Agriculture Department of the Valencian Region is promoting an ongoing pilot project to evaluate the efficacy of an integrated vector management program (IVM) based on the use of the SIT as the main method of control. The laboratory studies for evaluating the entomological efficacy of SIT through the phased conditional testing process recommended by World Health Organization and the International Atomic Energy Agency (WHO-IAEA) are addressed. This study describes the routine operating procedures and quality control parameters for the medium-scale rearing of sterile male Ae. albopictus. More than 15 million sterile males have been produced and released in an area of 80 ha between 2018 and 2020. Of the initial L1 larvae, we recovered 17.2% of male pupae after sex sorting to be sterilized and released on the field, while the rest of the pupae remained available to maintain the rearing colony. The residual percentage of females after sex sorting was on average 0.17%. The obtained values in terms of production and quality control as well as the proposed rearing methodology can be useful for designing a medium-scale mosquito-rearing pipeline.

In 2017, Xylella fastidiosa, a quarantine plant pathogenic bacterium in Europe, was detected in almond trees associated to leaf scorch symptoms in Alicante, a Mediterranean area in southeastern mainland Spain. The bacterium was detected by serological and molecular techniques, isolated in axenic culture from diseased almond trees, and identified as X. fastidiosa subsp. multiplex ST6. Inoculation experiments on almond plants in greenhouse trials with a characterized strain of X. fastidiosa subsp. multiplex ST6 isolated in the outbreak area have proved that it was able to multiply and systemically colonize inoculated plants. Disease symptoms characteristic of leaf scorch, as those observed in the field, were observed in the inoculated almond trees after one year. Furthermore, the pathogen was re-isolated and identified by molecular tests. With the fulfillment of the Koch’s postulates we have demonstrated that X. fastidiosa is the causal agent of the almond leaf scorch disease in the Alicante outbreak.

The EU plant health legislation enforces the implementation of intensive surveillance programs for quarantine pests. After an outbreak, surveys are implemented to delimit the extent of the infested zone and to manage disease control. Surveillance in agricultural and natural environments can be enhanced by increasing the survey efforts. Budget constraints often limit inspection and sampling intensities, thus making it necessary to adapt and optimize surveillance strategies. A sequential adaptive delimiting survey involving a three-phase and a two-phase design with increasing spatial resolution was developed and implemented for the Xylella fastidiosa demarcated area in Alicante, Spain. Inspection and sampling intensities were optimized using simulation-based methods. Sampling intensity thresholds were evaluated by quantifying their effect on the estimation of X. fastidiosa incidence. This strategy made it possible to sequence inspection and sampling taking into account increasing spatial resolutions, and to adapt the inspection and sampling intensities according to the information obtained in the previous, coarser, spatial resolution. The proposed strategy was able to efficiently delimit the extent of Xylella fastidiosa, while improving on the efficiency and maintaining the efficacy of the official survey campaign. From a methodological perspective, our approach provides new insights into alternative delimiting designs and new reference sampling intensity values.