TABLE CONTENTS

and eggs increased and root weight decreased, due to phytotoxicity. However, at 10 4 ppm, the
total number of eggs per plant was 35.7% lower than control. Caffeine was known for its
activity against snails, but not for phytoparasitic nematodes.
Resistance of Pasture Grasses and Legumes to Radopholus similis
Cobon, J. (1) & A. Pattison (2)
Queensland Department of Primary Industries and Fisheries
(1) 80 Meiers Rd, Indooroopilly, Qld 4068; (2) Centre for Wet Tropics, South Johnstone, Qld 4859.
There is increasing pressure on banana farmers to maintain ground cover around plants to
prevent the movement of soil, nutrients and pesticides from the farm. However, in banana
plantations there is potential for ground cover plants to host Radopholus similis. Therefore,
plants chosen as ground covers need to be agronomically suitable, resistant to R. similis and
hinder the migration of R. similis to the roots of bananas. Screening of potential shade
tolerant grasses and legumes for resistance to R. similis and companion planting with bananas
was conducted in glasshouse experiments.
Selected pasture species were established in pots and inoculated with 500 motile R. similis.
Ten weeks later, nematodes were extracted from the roots. Pasture species, identified as
resistant, were selected for an assay to determine their suitability to prevent R. similis
migrating to the roots of bananas. Mung beans (Vigna radiata) infected with R. similis were
grown in a pot on the outside of the selected pasture species and an in vitro banana plant
grown in the centre of the pot.
All grass species tested were found to be more resistant to R. similis than bananas with
Argentine Bahia (Paspalum notatum) more resistant than signal grass (Brachiaria
humidicola), Rhodes grass (Chloris gayana cv. Katambora) and Sabi grass (Urochloa
mosambicensis). Of the pasture legumes, Butterfly pea (Clitoria ternatea) and Pinto peanut
(Arachis pintoi) were more resistant to R. similis than banana.
Butterfly pea, grown alone or in combination with carpet grass (Axonopus affinis) or Bahia
grass, resulted in lower nematode populations in the roots of bananas. However, the banana
root weight was significantly reduced. Pinto peanuts and Bahia grass, grown separately,
reduced the number of nematodes recovered from the roots but did not reduce the weight of
the banana roots making them better companion plants as ground covers in banana
plantations.
Acknowledgements: Horticulture Australia Limited and Growcom provided funding for this
work under project FR02025.
5 th International Congress of Nematology, 2008 308