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Fuller's rose weevil (FRW), Naupactus cervinus, has recently become a pest of kiwifruit in New Zealand because export fruit infested with FRW eggs do not meet Japanese quarantine standards. Studies of FRW population genetics could be useful for: (i) deducing the number and geographic sources of FRW introductions to New Zealand, (ii) matching New Zealand FRW populations with appropriate strains of biological control agents and (iii) differentiating FRW from other closely related species which may be difficult to separate morphologically (especially as larvae). This paper describes preliminary results from sequencing of two gene regions, the ITS1 (internal transcribed spacer) region and the COI (cytochrome oxidase one) gene. These sequences were used to compare FRW from New Zealand, Australia, Hawaii and Chile. The results showed that the COI region would be more useful than ITS1 for future studies of FRW population genetics.

The use of grasses such as ryegrass and fescues infected with endophytic fungi of the Epichloë genus is widespread in New Zealand’s pastoral systems. Each endophyte–cultivar combination represents a distinctive genome–genome association, resulting in unique biological outcomes. The wider influence of these interactions on rhizosphere microbiology are not well characterised. This is important, because there may be opportunities or risks associated with selective disruption of the rhizosphere microbiota. We explored the interaction of two commercially used endophyte fungi, E. festucae var. lolii strains AR1 and AR37, within a genetically uniform breeding line of perennial ryegrass (Lolium perenne cv. Samson 11104) on the rhizosphere metabolome and the composition of the fungal, bacterial, and Pseudomonas communities. There were strong differences in the rhizosphere metabolomes between infested and non-infested ryegrass strains (P = 0.06). These were attributed to shifts in various n-alkane hydrocarbon compounds. The endophyte-associated alteration in rhizosphere metabolome was linked to changes in the total bacterial (P < 0.01) and fungal (P < 0.05) rhizosphere communities. Furthermore, there was varying levels of support for endophyte-specific (AR1 v. AR37) impacts on the bacterial and fungal communities. Pseudomonas bacterial communities were not influenced by endophyte infection of ryegrass (P = 0.834).

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