ABSTRACT
Invertebrates make up over 95% of animal biodiversity on Earth and contribute to multiple ecosystem services (ES) in natural and human-dominated systems. One such service, biological control (BC) of herbivorous pests, is a core component of sustainable intensification of agriculture, yet its importance is routinely overlooked. Here we report a macro-scale, cross-cultural assessment of the public visibility (or 'salience') of BC invertebrates, using high-throughput analysis of large bodies of digitized text (i.e., 'culturomics'). Using binomial scientific name frequency as proxy for visibility, we compared the extent to which a given species featured in webpages within either scientific media or the entire worldwide web, and in total search volume at varying spatial scale. For a set of 339â¯BC invertebrate species, scientific and internet coverage averaged 1020 and 1735 webpages, respectively. Substantial variability was recorded among BC taxa with Coleoptera, Hemiptera and Nematoda having comparatively high visibility. Online visibility exhibited large geographical variability ranging from France covering BC invertebrates on average in 1050 webpages versus Thailand or Indonesia on just 31-38. This work represents the first extensive use of culturomics to assess public visibility of insect-mediated ES. As BC uptake is dictated by stakeholders' access to (agro-ecological) information, our work identifies geographically-delineated areas that are differentially attuned to the concept of invertebrate BC, pinpoints opportunities for focusing education campaigns and awareness-raising, enables real-time tracking of BC public appeal, and informs public policy.
Subject(s)
Conservation of Natural Resources/methods , Ecosystem , Environmental Policy , Invertebrates , Animals , Biodiversity , HumansABSTRACT
Though often perceived as an environmentally-risky practice, biological control of invasive species can restore crop yields, ease land pressure and thus contribute to forest conservation. Here, we show how biological control against the mealybug Phenacoccus manihoti (Hemiptera) slows deforestation across Southeast Asia. In Thailand, this newly-arrived mealybug caused an 18% decline in cassava yields over 2009-2010 and an escalation in prices of cassava products. This spurred an expansion of cassava cropping in neighboring countries from 713,000 ha in 2009 to > 1 million ha by 2011: satellite imagery reveals 388%, 330%, 185% and 608% increases in peak deforestation rates in Cambodia, Lao PDR, Myanmar and Vietnam focused in cassava crop expansion areas. Following release of the host-specific parasitoid Anagyrus lopezi (Hymenoptera) in 2010, mealybug outbreaks were reduced, cropping area contracted and deforestation slowed by 31-95% in individual countries. Hence, when judiciously implemented, insect biological control can deliver substantial environmental benefits.
Subject(s)
Conservation of Natural Resources/methods , Crop Protection/methods , Hemiptera , Pest Control, Biological/methods , Rainforest , Animals , Asia, Southeastern , Commerce , Crop Production , Crops, Agricultural/economics , Manihot/economics , Plant Roots , Satellite Imagery , WaspsABSTRACT
The massive adoption of Bt cotton throughout China has been accompanied by outbreaks of secondary pests such as Adelphocoris spp. (Heteroptera: Miridae). The Adelphocoris group primarily consists of three species: A. suturalis, A. fasciaticollis and A. lineolatus, which greatly differ in geographical distribution and seasonal dynamics. However, the underlying drivers of these differences remain to be understood. The study of flight behaviour of these three species can yield important insight into their spatial and temporal dynamics and help explain their distribution. We examined flight propensity of the three Adelphocoris spp. under a range of biological and environmental conditions using a computer-monitored flight-mill. Gender and mating status only had minor effects on flight performance in these species, while age exerted great effects on it. Flight capacity was low for one-day-old adults and increased with age until day 10-13, then gradually decreased afterwards. Temperature and relative humidity affected flight propensity, with 20-23 degrees C and 64-68% RH considered optimal for flight of all three species. Between-species comparisons indicated that A. suturalis and A. fasciaticollis had similar flight distance and duration, which were significantly greater than for A. lineolatus. Our findings provide crucial information for understanding geographical distribution and seasonal occurrence and for developing regional forecasting and pest management protocols for Adelphocoris species.
Subject(s)
Flight, Animal , Gossypium/genetics , Heteroptera/physiology , Animals , Bacillus thuringiensis/genetics , China , Female , Geography , Humidity , Male , Plants, Genetically Modified , Seasons , Sexual Behavior, Animal , Species Specificity , Temperature , Time FactorsABSTRACT
The Asian parasitoid, Binodoxys communis (Gahan) (Hymenoptera: Braconidae), is a candidate for release against the exotic soybean aphid, Aphis glycines Matsumura (Hemiptera: Aphididae), in North America. In this study, we examined preferences by B. communis for the different developmental stages of A. glycines and investigated consequences of these preferences for parasitoid fitness. We also determined to what extent aphid defensive behaviours mediate such preferences. We found that B. communis readily attacks and successfully develops in the different A. glycines developmental stages. Binodoxys communis development time gradually increased with aphid developmental stage, and wasps took longest to develop in alates. An average (+/-SE) of 54.01+/-0.08% of parasitized A. glycines alatoid nymphs transformed into winged adult aphids prior to mummification. No-choice assays showed a higher proportion of successful attacks for immature apterous A. glycines nymphs compared to adults and alatoid nymphs. Also, choice trials indicated avoidance and lower attack and oviposition of adults and alatoid nymphs. The different aphid stages exhibited a range of defensive behaviours, including body raising, kicking and body rotation. These defenses were employed most effectively by larger aphids. We discuss implications for the potential establishment, spread and biological control efficacy of A. glycines by B. communis in the event that it is released in North America.