Diversity and impacts of key grassland and forage arthropod pests in China and New Zealand: An overview of IPM and biosecurity opportunities

Abstract

For both New Zealand and China, agriculture is integral to the economy, supporting primary production in both intensive and extensive farming systems. Grasslands have important ecosystem and biodiversity functions, as well providing valuable grazing for livestock. However, production and persistence of grassland and forage species (e.g. alfalfa) is not only compromised by overgrazing, climate change and habitat fragmentation, but from a range of pests and diseases, which impose considerable costs on growers in lost production and income. Some of these pest species are native, but increasingly, international trade is seeing the rapid spread of exotic and invasive species. New Zealand and China are major trading partners with significant tourist flow between the two countries. This overview examines the importance of grasslands and alfalfa in both countries, the current knowledge on the associated insect pest complex and biocontrol options. Identifying similarities and contrasts in biology and impacts along with some prediction on the impact of invasive insect species, especially under climate change, are possible. However, it is suggested that coordinated longitudinal ecological research, carried out in both countries using sentinel grass and forage species, is critical to addressing gaps in our knowledge of biology and impact of potential pests, along with identifying opportunities for control, particularly using plant resistance or biological control.

Sustainable Management of Medicago sativa for Future Climates: Insect Pests, Endophytes and Multitrophic Interactions in a Complex Environment

“…This includes shifts in insect distribution (Battisti and Larsson, 2015;Ricciardi et al, 2021), loss of biodiversity (Bellard et al, 2014), and associated impacts on ecosystem services (Pedrono et al, 2016). There will also be increased biosecurity impacts as pathways and vectors associated with trade and tourism provide the means to move high impact pests and diseases, rapidly and across vast distances (McNeill et al, 2021;Ricciardi et al, 2021).…”

“…Climate change presents an obvious challenge, not only because there will be more instability in climatic events such as drought or floods, but economically valuable plant species will potentially be exposed to new pests and plant diseases due to range expansion, (Trebicki et al, 2017;Ricciardi et al, 2021), either through natural dispersal or spread along trade and tourism pathways (McNeill et al, 2021). Elevated temperatures will have both negative and positive consequences for biological control (Thomson et al, 2010;Gerard et al, 2013), and plant defense responses to pathogens (Venkatesh and Kang, 2019).…”

“…The plant is considered integral to the transformation of traditional agriculture (Zhang et al, 2018;Xu et al, 2021). It also provides an important alternative to overgrazing of ecologically sensitive grassland environments (Zhang et al, 2018;McNeill et al, 2021). Medicago sativa is seen as an important crop in the development of animal husbandry, increasing farmers' income, and promoting social and economic development in rural areas (Li, 2019;Xu et al, 2021).…”

Nitrogen addition results inMedicago sativaswitching nitrogen sources

“…After germination, seedlings with similar size and healthy appearance were transplanted into pots (H 25 cm × D 20 cm) with soil media. The soil, classified as Haplic Calcisol (IUSS Working Group WRB, 2014), was collected from a typical steppe grassland in Xilingol, Inner Mongolia, China, where M. sativa has been cultivated as forage for many years (Deng et al 2014;McNeill et al 2021). The soil was completely homogenised prior to planting.…”

Occurrence, Distribution, and Transmission of Alfalfa Viruses in China

“…Aphids, an important worldwide pest on alfalfa, is the vector for a range of viruses including AMV, Bean leafroll virus (BLRV), and Alfalfa leaf curl virus (ALCV) [ 20 , 21 , 22 , 23 ]. However, thrips are another major insect pest in alfalfa in China [ 24 , 25 ]. Thrips are equipped with rasping-sucking mouthparts, usually having high reproductive capability and a short generation time.…”