The encyrtid genus Comperiella Howard has so far not been reported in the Philippines, where there is currently an outbreak of the coconut scale insect Aspidiotus rigidus Reyne particularly in the southern parts of the island of Luzon and in some areas in Mindanao. Among Comperiella species, only C. unifasciata Ishii has been reported as a parasitoid of A. rigidus. We report not only new sightings of this parasitoid genus in the Philippines from surveys conducted in parts of the provinces of Laguna and Batangas, but also the discovery of a possibly new species that, like C. unifasciata, has been found to parasitize A. rigidus at a high rate. These findings have presented a potential of biological control against the coconut scale insect problem that has threatened the coconut industry in the country.

The coconut scale insect, Aspidiotus rigidus Reyne, caused a major pest outbreak in coconut plantations and stands in the Southern Tagalog region of Luzon Island in the Philippines between 2010 and 2015. To determine if parasitism by Comperiella calauanica Barrion, Almarinez and Amalin, a native encyrtid, could have been a factor in the eventual management of the outbreak by 2015, we estimated and assessed its parasitization levels on A. rigidus colonies on field-collected samples from selected points in three provinces in the Southern Tagalog Region across three sampling periods. We observed that C. calauanica consistently occurred only in areas where A. rigidus populations occurred, with high parasitization levels in the Southern Tagalog sites from 2014 to 2015. Results of correlation and regression of total scale count against parasitized scale count suggest putative host density-dependent parasitism by C. calauanica in the field. A marked decrease in the abundance of A. rigidus was recorded concurrently with visually observable recovery of coconut trees from the third quarter of 2014 up to the second quarter of 2016. Similar results of significant reduction in A. rigidus populations concurrent with high percent parasitization by mass-reared and released C. calauanica were found in the Zamboanga Peninsula from 2018 to 2020. Our findings and observations altogether suggest that host-specific parasitization by C. calauanica effected biological control, which may have contributed to the eventual management of the A. rigidus outbreak in the Southern Tagalog Region, and also in the Zamboanga Peninsula where similar recovery of coconut trees were observed within a year after inoculative releases of C. calauanica.

Summary Plants respond to stress or damage by releasing volatile compounds, primarily for defense purposes. These volatiles function as signals for diff erent interactions of the plant with its environment. In this study, the volatile chemical profi le of healthy Garcinia mangostana L. (mangosteen) leaves was compared against leaves infested with the scale insect, Aspidiotus rigidus Reyne (Hemiptera: Diaspididae) through solid phase microextraction (SPME) coupled with gas chromatography-mass spectrometry (GC-MS). Analyses revealed that leaves emit the terpene kaur-16-ene in response to A. rigidus infestation. Kaur-16-ene is a precursor of gibberellin, a plant hormone for growth and development. The results suggest that the emission of kaur-16-ene in infested G. mangostana may play a role relevant in increasing the resistance of the plant towards infestations by herbivores.

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Purpose – The purpose of this paper was to look into the impacts brought about by climate change to the food security in Saguday, Quirino in the Philippines. Design/methodology/approach – A framework for developing community food security was utilized which identified the need to mitigate and address inherent externalities in a community such as flooding due to climate change as necessary preconditions to attaining a food secure environment. The study highlighted Saguday’s risk to externalities using risk assessment and modelling. Findings – Data from literature reviews and agency reports were validated by key informant interviews of local and national officials and focus group discussions with different stakeholder groups. Originality/value – A modification of the Urban Food Security Planning Process developed by Taylor and Carandang (2010, 2011) was utilized to address the local government unit’s need to mitigate and manage the inherent geographical risks that Saguday has in relation to its agricultural and food productivity.