Biosecurity, pests, weeds and diseases
Location: East Chapman Research Station.
Half the trial site was cultivated to 30cm at the break of the season and the whole site was normally cultivated. Weeds were then sprayed with Roundup at 1 1/ha prior to seeding with an eight run cone seeder. The plots were kept weed free during the year by hand weeding. The root distribution was calculated from soil cores taken in 20 cm increments on 20 August. Aphid cortrol consisted of spraying every two weeks with Pirimor at 140 g/ha between July and October. Lorsban at 150 ml/ha was used for the last two sprays, which appeared to have some affect on the pasture growth and may have compounded the results slightly. Both cultivars displayed an early response to deep ripping, however this response had faded out by 8 weeks after germination and had no effect on seed yield. Blue-green aphids were at the highest numbers between 8 and 11 weeks, and had virtually disappeared by 13 weeks.
Number of Pages
Nutt, B, and Laslett, M K. (1988), Effect of deep ripping and aphid infestation on pasture production.. Department of Agriculture and Food, Western Australia, Perth. Report.