Arabis mosaic virus (AMY) , in association with its vector Xiphinema diversicaudatum, is recorded for the first time in New Zealand.It was found occurring naturally on tamarillos (tree tomatoes) and was transferred experimentally to produce symptoms on Buttercup squash, cowpea, cucumber, french bean, lupin, Petunia, soybean, and tobacco. AMY was also transmitted to celery, coriander, pea, and sweet pea, but produced no symptoms in these hosts.No nematode or seed transmission experiments were attempted. Surveys showed the nematode vector to be present in only small numbers but regularly associated with tamarillo plants infected with AMY.The host range, physical properties, serology, and electron microscopy of the virus suggest that it is a strain of arabis mosaic virus.

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Tomato aspermy virus was found in chrysanthemum in New Zealand for the first time, in commercial gardens in Christchurch, Wanganui, and Auckland. The virus was transferred experimentally to marigold, nasturtium, aster, capsicum, chrysanthemum, tamarillo, lettuce, tomato, Nicotiana glutinosa L., Chenopodium amaranticolor Coste & Reyn., tobacco, black nightshade, New Zealand spinach, and zinnia. The longevity of the virus was between 7 and 11 days and the thermal inactivation point between 65°and 70°c. The dilution end point of the virus was between 1-50000 and 1-100000. The virus was transmitted by the green peach aphid. cv. 'Short Prickly') to detect possible contamination with cucumber mosaic virus.For electron microscopy the virus was partly purified from sap extracted from TAV-infected N. glutinosa plants. After being heated at 51°c for 5 minutes, sap was clarified by centrifuging at 15 000 rpm for 15 minutes and then sedimented by centrifuging for 2 hours at 30 000 rpm in the 30 rotor of a Spinco model L ultracentrifuge -.The partially purified virus preparation was negatively stained with uranyl acetate and observed in the electron microscope.

One hundred and fifty-two collections of red clover (Trifolium pratense L.) plants (25 plants per collection) were made throughout New Zealand. When tested on virus indicator plants 24% of North Island and 80% of South Island collections were free from virus. White clover mosaic virus occurred in 35% of collections. pea mosaic virus in 5%. and an additional 8.5% contained both viruses. Lucerne mosaic virus was not detected.

With seed from tomato plants infected with tobacco mosaic virus. infection occurred less frequently in seedlings of the variety Potentate when the seed-coats were elevated on the cotyledons than when they were not. Elevation of the seed-coat, however, did not markedly affect the proportion of seedlings infected in the variety V548, indicating a possible varietal difference in this character. No seedlings of either variety became infected when raised from seed from infected plants, which was extracted using hydrochloric acid.