Action

Pest regulation: Use organic fertilizer instead of inorganic

How is the evidence assessed?
  • Effectiveness
    0%
  • Certainty
    10%
  • Harms
    10%

Source countries

Key messages

Pest regulation (0 studies)

Crop damage (0 studies)

Ratio of natural enemies to pests (0 studies)

Pest numbers (2 studies): One replicated, randomized, controlled study from the USA found more aphids in plots with organic fertilizer, compared to inorganic fertilizer, in some comparisons, but another one found similar numbers of aphids in the same study system.

Natural enemy numbers (0 studies)

About key messages

Key messages provide a descriptive index to studies we have found that test this intervention.

Studies are not directly comparable or of equal value. When making decisions based on this evidence, you should consider factors such as study size, study design, reported metrics and relevance of the study to your situation, rather than simply counting the number of studies that support a particular interpretation.

Supporting evidence from individual studies

  1. A replicated, randomized, controlled study in 1991 in a broccoli field in the Salinas Valley, California, USA (same study as (2)), found more pests in plots with organic fertilizer, compared to inorganic fertilizer. Pest numbers: More aphids were found in plots with organic fertilizer, compared to inorganic fertilizer, in one of eight comparisons (in plots with bare soil, on two of four sampling days: data reported as model results). Methods: Plots (10 x 10 m) had organic fertilizer (compost) or inorganic fertilizer (amounts not reported; four plots for each). Cabbage aphids Brevicoryne brassicae and green peach aphids Myzus persicae were sampled in each plot with two yellow pan traps (12 x 8 x 8 cm traps, 12, 22, 43, and 52 days after transplanting). Pests were also sampled by heat extraction from broccoli leaves (22, 32, 42, 52 and 62 days after transplanting).

    Study and other actions tested
  2. A replicated, randomized, controlled study in 1991 in a broccoli field in the Salinas Valley, California, USA (same study as (1)), found similar numbers of pests in plots with organic or inorganic fertilizer. Pest numbers: Similar numbers of aphids were found in plots with organic or inorganic fertilizer (data not reported).  Methods: Plots (10 x 10 m) had organic fertilizer (compost) or inorganic fertilizer (amounts not reported; four plots for each). Cabbage aphids Brevicoryne brassicae and green peach aphids Myzus persicae were sampled on 50 broccoli leaves from 50 plants in each plot (1990: every 2 weeks; 1991: every 10 days).

    Study and other actions tested
Please cite as:

Shackelford, G. E., Kelsey, R., Robertson, R. J., Williams, D. R. & Dicks, L. V. (2017) Sustainable Agriculture in California and Mediterranean Climates: Evidence for the effects of selected interventions. Synopses of Conservation Evidence Series. University of Cambridge, Cambridge, UK.

Where has this evidence come from?

List of journals searched by synopsis

All the journals searched for all synopses

Mediterranean Farmland

This Action forms part of the Action Synopsis:

Mediterranean Farmland
Mediterranean Farmland

Mediterranean Farmland - Published 2017

Mediterranean Farmland synopsis

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