Ecological engineering for rice pest suppression in China. A review

Abstract

Ecological engineering for pest suppression aimed at promoting ecosystem services of biological control, involves a range of environmentally-benign approaches to conserve and promote arthropod natural enemies and suppress pest populations, and thus reduce the need for insecticide use. Major components in rice pest management involve providing vegetation that favors parasitoid overwintering during the fallow seasons, growing nectar-producing flowering plants on the rice bunds to enhance the biocontrol function, and planting trap plants around rice fields to minimize the initial populations of pests. Complementary tactics involve using sex pheromone traps and mass-releasing Trichogramma spp. parasitoids to reduce the densities of Lepidoptera pests, and synergistically culturing ducks or fish to reduce other planthoppers. After a decade of laboratory and field research accompanied by on-farm demonstrations, ecological engineering for rice pest management has shown growth in both the underlying body of theory and practical adoption, especially in China. Ecological engineering approaches have been listed as a China National Recommendation by the Ministry of Agriculture and Rural Affairs of the People’s Republic of China (MARA) since 2014. We feel this is worth documenting, especially because only a portion of that work has been reported in English-language journals so would otherwise remain “invisible” to the international scientific community. This study is the first time to systematically review the research that has allowed this rapid development and uptake in China, highlighting priorities for future research that will enhance the prospects for ecological engineering in this and other agricultural systems internationally.

The Low Congruence between Plant and Animal Diversity in Field Ridges of Intensively Managed Paddy Landscapes, China

“…and chemical properties of the ridge have the greatest effect on plant and animal diversity [ 39 ]. In addition, as one semi-natural habitat type, the ridge also provides a better habitat for plants and animals than the interior of the field [ 44 , 45 ]. Under suitable environmental conditions, the greater the habitat area, the higher the biodiversity [ 46 ]; thus, a wider ridge represents a larger growth, development, and activity area, a more hidden space for organisms, and should have a higher diversity of plants and animals [ 47 ].…”

Escaping the Lock-in to Pesticide Use: Do Vietnamese Farmers Respond to Flower Strips as a Restoration Practice or Pest Management Action?

“…This suggests that some of the benefits of ecological engineering (i.e., increasing natural enemy abundance or efficiency) could be achieved even where farmers make prophylactic insecticide applications (model 5, Figure 1). In such a case, ecological engineering would only be adopted because it 'counters' the negative effects of prophylactic applications (i.e., increasing resilience by preventing pest outbreaks in the face of intense, prophylactic insecticide use), although it might also bring other benefits to the system including providing habitat for wildlife, especially pollinators [7,37,44,45]. One drawback of resilience-or the perception of resilience-provided by flower strips in intensive systems, is that it could lead to even greater levels of pesticide use if flower strips are regarded as an 'insurance' (model 6, Figure 1) against pest resurgence, thereby allowing farmers to increase applications or apply insecticides indiscriminately.…”

“…Ecological restoration using flower strips or otherwise diversified habitat is expected to bring several benefits besides improving the natural regulation of arthropod pests [14,44,45]. Furthermore, as a restoration practice, farmers might have been expected to reduce their use of other pesticides because herbicides and fungicides are also hazardous to the environment and some products are associated with outbreaks of insect pests [40].…”

Land consolidation impacts the abundance and richness of natural enemies but not pests in small‐holder rice systems

“…It is not clear whether these landscape‐level large semi‐natural habitats can compensate for the loss of biodiversity due to land consolidation. This question is relevant when managers are considering investing in agri‐environment measure (AEM) or Ecological Engineering (EE), such as planting grass or flower strips to enhance the linear habitats, as a way to conserve farmland biodiversity and ecosystem services (Horgan et al., 2016; Kleijn & Sutherland, 2003; Uthes & Matzdorf, 2013; Zhu et al., 2022; Zou, 2024). For example, a meta‐analysis based on European studies found that the effectiveness of AEM in improving pollinator diversity is determined by the ecological contrast (i.e.…”