Rosialda PBR, Quibod MNRM, Day MD. Preliminary Study on the Distribution of the Introduced Gall-forming Fly, Cecidochares connexa (Macquart) (Diptera: Tephritidae) for the Biological Control of the Invasive Alien Weed Chromolaena odorata (L.) R.M. King & H. Rob. (Asteraceae) in the Philippines. Philippine Journal of Science 148(1): 189-196.

http://philjournalsci.dost.gov.ph/images/pdf/pjs_pdf/vol148no1/preliminary_study_on_the_distribution_of_gall_forming_fly_.pdf

The distribution of Cecidochares connexa (Macquart), a biological control agent of the invasive plant Chromolaena odorata (L.) R.M. King & H. Rob. was determined around the three main islands – Luzon, Visayas, and Mindanao – in the Philippines. A total of 105 sites in 17 localities with C. odorata were surveyed for the presence of C. connexa. Cecidochares connexa was present at 82 sites in eight localities, limited to around Visayas and Mindanao. Some sites where the gall fly was reported were up to 400 km from the initial release sites around Davao, Mindanao. Cecidochares connexa was not found at any of the nine localities surveyed around Luzon. Visual observations showed that the gall fly is having some impact on C. odorata, as evidenced by dead branches and stems. These results show that C. connexa has firmly established in the country and that it has the ability to disperse long distances to new areas. It is likely that C. connexa will continue to disperse further with time. However, a more robust study regarding its presence in other parts of the country and its effectiveness as a biological control agent is needed.

Singh D, Slik FJW, Jeon YS, Tomlinson KW, Yang X-D, Wang J, Porazinska DL, Adams JM. Conversion of Asian tropical forests to monoculture rubber plantation reduces small metazoan α-diversity, and overall diversity. Scientific Reports. DOI: 10.1038/s41598-019-42333-4

Abstract: Tropical rainforests play important roles in carbon sequestration and are hot spots for biodiversity. Tropical forests are being replaced by rubber (Hevea brasiliensis) plantations, causing widespread concern of a crash in biodiversity. Such changes in aboveground vegetation might have stronger impacts on belowground biodiversity. We studied tropical rainforest fragments and derived rubber plantations at a network of sites in Xishuangbanna, China, hypothesizing a major decrease in diversity with conversion to plantations. We used metabarcoding of the 18S rRNA gene and recovered 2313 OTUs, with a total of 449 OTUs shared between the two land-use types. The most abundant phyla detected were Annelida (66.4% reads) followed by arthropods (15.5% reads) and nematodes (8.9% reads). Of these, only annelids were signifcantly more abundant in rubber plantation. Taken together, α- and β-diversity were signifcantly higher in forest than rubber plantation. Soil pH and spatial distance explained a signifcant portion of the variability in phylogenetic community structure for both land-use types. Community assembly was primarily infuenced by stochastic processes. Overall it appears that forest replacement by rubber plantation results in an overall loss and extensive replacement of soil micro- and mesofaunal biodiversity, which should be regarded as an additional aspect of the impact of forest conversion.