Crops
 
Tree nurseries Crops main menu
  Pests in tree nurseries
 
General
Scouting & Monitoring
Contact with beneficials
Chemical corrections
Thrips
Spider mites
Aphids
Black vine weevil
Sciarids
Caterpillars
General remarks concerning biological control in tree nurseries
 
Before introducing beneficials, the greenhouse and plants should be free of harmful pesticide residues.
Before the beginning of your cultivation discuss with your advisor a plan of approach for the whole season.

 
Scouting & Monitoring
 
Use yellow Bug-Scan® sticky traps for (timely) detection of flying insects. During the heating of the greenhouse hang min. 20 yellow sticky traps per ha to detect the first flying insects.
Also use yellow Bug-Scan® sticky traps during the cultivation. Count and register during minimum the first 10 weeks of your cultivation the different species of flying insects which are captured on the sticky traps.

 
Contact with beneficials
 
Follow up carefully the user's instructions; always pay attention to the icons on the packing. If necessary consult the Icon Guide.
Introduce beneficials preferably early in the morning.
If you want to store the beneficials for a short time, you have to reckon with the storage temperature and the use by date which are mentioned on the packing.

 
Chemical corrections
 
If a chemical correction has been inevitable, use as much as possible selective chemical crop protection products. Try to apply chemical corrections on local spots.
In case of doubt about the side effects of pesticides, contact your advisor or consult the Side Effects Manual which is available on www.biobest.be.

 
Biological control of thrips
  Amblyseius-System (A.B.S) (predatory mite - Amblyseius cucumeris in sachets)
 
Hang yellow and/or blue sticky traps for the detection of thrips (min. 1 sticky trap/100 m²).
Introduce 1 sachet/m². Repeat regularly (depending on the thrips pressure and the countings on the sticky traps) e.g. every 6 weeks or every 4 weeks.
Warning:
The products Amblyseius-Breeding-System (ABS) and Amblyseius-Slow-Release-System (ASR), which contain the predatory mite Amblyseius cucumeris delivered in breeding sachets, also contain Mold mites (Tyrophagus putrescentiae) and bran. Under certain circumstances such as a moist greenhouse climate or when using large quantities of breeding sachets, Mold mite population can increase to the point of causing damages in some crops (e.g. cucumbers). When planning to use these products in crops where they have never been used before, we recommend to first perform a small-scale trial or to discuss this with your Biobest advisor or supplier.
  Amblyseius-System (predatory mite - Amblyseius cucumeris)
 
Disperse 100 Amblyseius cucumeris/m²/week in thrips hot spots or on places which are sensitive to thrips. When no ABS-sachets are used, introduce then 250 predatory mites/m²/week.
Warning:
The products Amblyseius-Breeding-System (ABS) and Amblyseius-Slow-Release-System (ASR), which contain the predatory mite Amblyseius cucumeris delivered in breeding sachets, also contain Mold mites (Tyrophagus putrescentiae) and bran. Under certain circumstances such as a moist greenhouse climate or when using large quantities of breeding sachets, Mold mite population can increase to the point of causing damages in some crops (e.g. cucumbers). When planning to use these products in crops where they have never been used before, we recommend to first perform a small-scale trial or to discuss this with your Biobest advisor or supplier.
  Hypoaspis-System (predatory mite - Hypoaspis miles)
 
After planting introduce preventive minimum 100 Hypoaspis/m² to control the larval and pupal stages of thrips.
  Orius-System (predatory mite - Orius spp.)
 
Disperse Orius species in hot spots to control thrips.
Biological control of spider mites
  Phytoseiulus-System (predatory mite - Phytoseiulus persimilis)
 
Introduce minimum 6 Phytoseiulus/m² as soon as the first spider mites are detected. The exact amount depends on the severeness of the spider mite infestation.

In and especially around hot spots: 20 to 40 Phytoseiulus/m².
Spread well in the working direction.
  Feltiella-System (gall midge - Feltiella acarisuga)
 
To support Phytoseiulus at spider mite hot spots.

Introduce locally 1 pot (250 pupae) during 4-6 weeks.
Remark: The gall midges have an excellent ability to search, but they can become disorientated by frequent use of a sulphur steamer.
  Californicus-System (predatory mite - Amblyseius californicus)
 
Introduce preventive 4-6 Amblyseius californicus/m² in the whole greenhouse. Repeat regularly (depending on the spider mite pressure), but at least every 3 weeks. Start with this introduction after the waiting period of the last chemical treatment, but certainly before the end of March.
This predatory mite can survive a few weeks without nourishment and is resisted against low temperatures in the early spring.
Biological control of aphids
  Aphidius-System (parasitic wasp - Aphidius colemani)
 
Preventive: Introduce 0,1 Aphidius colemani/m² per week
Curative: After detection of aphids: introduce minimum 0,5 Aphidius colemani/m² per week, during 3 weeks; until a sufficient number is parasitized.
Disperse Aphidius in Bio-Boxes (± 25 boxes/ha).
  Ervi-M-System (parasitic wasp - Aphidius ervi)
 
Introduce Aphidius ervi if Macrosiphum euphorbiae (Potato aphid) or Aulacorthum solani (Glasshouse potato aphid) are occurring.
Introduce 2 Aphidius/m² in and around hot spots.

  Aphelinus-System (parasitic wasp- Aphelinus abdominalis)
 
Introduce Aphelinus abdominalis if Macrosiphum euphorbiae (Potato aphid) or Aulacorthum solani (Glasshouse potato aphid) are occurring.
Introduce 2 Aphelinus/m² in and around hot spots.
  Aphidoletes-System (gall midge - Aphidoletes aphidimyza)
 
Preventive: Introduce 0,1-0,2 Aphidoletes/m²/week
Curative: When aphids are detected in the crop, introduce 0,5-1 Aphidoletes/m²/week
Open the bottle and place this bottle under the aphid hot spot, or disperse Aphidoletes, in heaps, on a moist substratum.
Remark: The gall midges have an excellent ability to search, but they can become disorientated by frequent use of a sulphur steamer.
  Adalia-System (ladybird - Adalia bipunctata)
 

Introduce 50-100 Adalia-larvae/m² in the immediate neighbourhood of aphid hot spots, as an addition to Aphidius and Aphidoletes.
Biological control of black vine weevil
  Vine weevil control can be done during if larvae are present and the soil temperature is minimum 12°C.
  Heterorhabditis-System (insect parasitic nematodes - Heterorhabditis megidis packed per 50 million)
 
Use at low infestation of black vine weevil larvae, 0,5 million nematodes/m².

At a severe damage the dose has to be increased to 1 million nematodes/m².
Biological control of sciarids
  Hypoaspis-System (predatory mite - Hypoaspis miles)
 
Introduce preventive and immediately after cutting Hypoaspis miles 200 to 300/m².

When a serious infestation is expected, increase the dose of Hypoaspis to 500-1.000 per m² or spray the soil with insect parasitic nematodes Steinernema feltiae.
  Steinernema-System (insect nematodes Steinernema feltiae packed per 50 million or 200 million)
 
To support the predatory mite Hypoaspis.

After a treatment it takes ca. 2 weeks before the population of adult midges decreases (control the sticky traps).

At an extreme infestation of sciarids it might be necessary to spray a second time.
Biological control of caterpillars
  Attract® pheromone lures
 
• Hang 2 catch lamps/ha above the crop, to catch as many moths as possible.

Hang minimum 2 Attract® pheromone lures per ha.

  • Hang the Attract® pheromone lures minimum 50 m from each other to prevent a mixture of the pheromones.
  • Replace the pheromone capsules regularly (every 4 weeks).
 

 

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