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Providing evidence to improve practice

Individual study: Field application of brassicaceous amendments for control of soilborne pests and pathogens

Published source details

Zasada I.A., Ferris H., Elmore C.L., Roncoroni J.A., MacDonald J.A., Bolkan L.R. & Yakabe L.E. (2003) Field application of brassicaceous amendments for control of soilborne pests and pathogens. Plant Health Progress, Online


This study is summarised as evidence for the intervention(s) shown on the right. The icon shows which synopsis it is relevant to.

Incorporate plant remains into the soil that produce weed-controlling chemicals Natural Pest Control

A series of four randomised, replicated trials in 1999-2001 in cut flower production systems in California, USA (Zasada et al. 2003) found incorporating broccoli Brassica oleracea and other brassica plant residues had variable success in controlling weeds. One experiment found no effect on weed survival (redroot pigweed Amaranthus retroflexus, annual bluegrass Poa annua, little mallow Malva parviflora) as broccoli material (covered by tarpaulin) increased from 4.0 to 8.4 t dry matter/ha. One experiment found broccoli residue reduced bindweed Convolvulus arvensis populations compared to controls (approximately 56% reduction), while Brussels sprouts B. oleracea and horseradish Armoracia lapathifolia residues did not. One experiment found that broccoli residues and a tarpaulin reduced the number of common purslane plants compared to other tarpaulin treatments. Addition of a tarpaulin to plots with incorporated broccoli residue generally had no effect. Broccoli plant material was collected after floret harvesting and applied at 2.6-8.4 t/ha, approximately 10-30 cm deep. Plots were left uncovered, or covered with a tarpaulin sheet. There were four replicates. Weed species were counted in 0.25 m² quadrats.