Summary

1. In order to create a solid foundation for this project, it will summarise existing knowledge on the biology of Lucerne Seed Wasp (LSW), as well as other insect pests that are biologically similar. The resulting report will encapsulate the current body of knowledge of seed-feeding wasps and other insects, their natural enemies, and known methods for control. This review will also yield candidate primer sequences for developing a PCR test for presence/absence of LSW DNA. This work will be conducted by Dr. Seago in the Agricultural Scientific Collections Unit (ASCU) at the DPI’s Orange Agricultural Institute (OAI).
2. In order to capture more data about the emergence timing, flexibility thereof, and regional variation in LSW populations, we will collect live LSW adults and larvae from Lucerne paddocks in NSW and SA (contingent on industry participation). We will use some of these samples as a source of DNA to develop a PCR test for LSW. Live LSW will be used to establish viable glasshouse/CT populations at OAI. These will enable us to determine how LSW pupation and emergence time respond to changes in temperature and humidity, and whether these patterns are consistent between populations (e.g. in NSW vs. SA wasps). We will also determine whether non-lucerne weeds (e.g. clover/trefoil) can act as reservoir hosts for LSW. This work will be jointly conducted by a postgraduate student TBD, Prof. Gurr, Dr. Seago, and ASCU technical staff.
3. In order to develop a soil sampling approach to predicting LSW populations, we will collect soil samples from participating growers and trial several methods of quantifying infested seeds. These include light microscopy, PCR testing, and (time permitting) qPCR, which will identify both LSW and its hyperparasites simultaneously. We will also analyse LSW dispersal through rubidium chloride labelling. Analysing population genetic data of LSW in NSW and SA will reveal this species’ dispersal patterns on a larger scale.

Program

Pasture Seeds

Research Organisation

(DPI) The Crown in right of the State of New South Wales acting through the Department of Primary Industries within Regional NSW

Objective Summary

The central objective of this project is to expand our understanding of the biology and life history of the Lucerne seed wasp (LSW) in order to equip Lucerne seed producers to effectively manage this pest. Towards this goal, we will conduct three phases of study with the following individual objectives:
1. Review the scientific literature on Eurytomidae (seed wasps), their natural enemies, and other seed parasite insects. Identify potential primer sequences for amplifying DNA from LSW. Summarize results of review in report and manuscript form.
2. Investigate the life history and host breadth of LSW through laboratory (glasshouse and CT room) rearing of multiple generations.
3. Develop a soil sampling approach for determining overwintering population levels of LSW. Additionally, examine LSW population dynamics at both local (within/ between paddocks) and regional (SA-NSW) scales.