Development of IPM-strategies for field vegetables

Transcription

1 Development of IPM-strategies for field vegetables (onion, lettuce) DFFE-project Annie Enkegaard, AU-DJF

2 The project Holistic management of weeds, diseases and pests using physical, biological i l and chemical methods for prevention and control 1) Biological control of pests 2) Biological control of diseases 3) Physical weed control 4) Testing IPM-strategies under field conditions 5) Pesticides residues after harvest 6) Communication initial lab, semifield and field experiments and determination of strategies test of strategies under field conditions + analyses of pesticide traces in harvested crops Partners: Aarhus University, growers, Horticultural Advisory Services, robot engineering company 2

3 WP1 Pests Biological control of the onion fly, Delia antiqua Augmentative releases Commercially available predators young larvae Predatory mites (Stratiolaelaps miles, Hypoaspis aculeifer, Macrocheles robustulus) + rove beetle (Atheta coriaria) Biological control of aphids in lettuce Flower strips Augmentative releases Commercially available predators / parasitoids

4 WP1 Onion fly, lab/semifield results Initial screening experiments The rove beetle has the highest predation larvae/day at 12-20ºC The rove beetle will lay eggs when fed on onion fly larvae 10/dag at 20ºC for 1-1½ week Nice functional response onion fly larvae eaten/day Semifield experiment Short-term (2½ weeks) Semifield experiment: 55% reduction (significant) in density of density onion fly larvae after treatment with Atheta (1:1 adult:larva), released prior to infestation + 1 and 2 weeks after.

5 WP1 Aphids in lettuce, results Initial field experiments Failed due to climatic conditions Greenhouse experiment Lettuce aphids, 24:15ºC (day:night), 16:8 l:d Short-term term (4 weeks) Control, weekly releases of parsitoids / predators / both Good effect from parasitoids 300 a a b b a a b b plant # bladlus aphids/ / plante Kontrol Banker plants Udsætninger Banker + udsætninger Control parasitoids predators both behandling

6 WP2 Diseases Biological control of diseases in onion (downy mildew, Peronospora destructor; t leaf blight, Botryotinia ti i squamosa; grey mould, Botrytis allii) Use of antagonistic microorganisms for prevention/control Biological control of downy mildew of lettuce, Bremia lactucae Use of antagonistic microorganisms for prevention/control The antagonistic microorganisms may function by direct competition with plant pathogens or by increase plant tolerance

7 WP2 Lettuce, results Greenhouse experiments with lettuce 10 commercial antagonist products tested for effect on disease (downy mildew) and plant growth 7 products (3 Mycorrhiza; 2 fungal) stimulates growth No direct effect on downy mildew Serenade ASO (Bacillus subtilis) chosen for foliar applications

8 WP2 Initial investigations System for mass production of plants inoculated with mycorrhiza Evaluation of onion/lettuce variety, mycorrhiza product and growth medium on plant growth and on colonization with mycorrhiza Growth-promoting effect of mycorrhiza influence when lettuce plants are susceptible The Symbiom mycorrhiza product was chosen for plant inoculation t % Lettuce e/onion roo coloniz ation with myco orrhiza Glomus clariodeum Myco-Ymp Symbiom Shoot dry weigh (g) Onion Lettuce Mycorrhiza product G. clariodeum Myco-Ymp Symbiom Mycorrhiza product

9 WP3 Weeds intra row intra-row Mechanical intra-row weed control in onion and lettuce Replace intra-row hand-weeding with mechanical methods Non-selective and selective methods Crop Onion Transplants Hour/ha for hand handweeding sown

10 WP3 results, Non-selective tools without intelligence Finger weeding Finger weeding, torsion weeding, weed harrowing Finger weeding and torsion weeding provide 70-90% intra-row row weed control and 50-70% reduction in need for manual weeding of residual weed Cheaper than robots but require large experience Selective tool with intelligence robotic weeding Robotic weeding 70-80% intra-row weed control and 50-60% reduction in need for manual weeding of residual weed Does not impact the crop Less concentration needed Longer working time

11 WP5 Pesticide residues Measurements of residues from pesticides id used in field experiments Mass spectrometer analyses To be conducted in 2012 from harvested lettuce heads and onions

12 WP4 IPM-strategies under field conditions Biological and mechanical strategies determined from results are combined with use of pesticides id (100%, 75%, 50% and 0% of recommended dosages) Experiments at Flakkebjerg, 1 onion grower, 1 lettuce grower Control of diseases separated from control of pests for layout, see handouts 4 replicates, GEP, randomized complete block design, width 5 m, length 6 m Robot weeding against intra-row weeds in all treatments, inter-row hoeing in all treatmentst t

13 WP4 Onion Onion, planted week 19 (9 th May), harvest week 35 Biocontrol, diseases Mycorrhiza inoculation prior to planting; B. subtilis as foliar spray Biocontrol, pests Releases of rove beetles and predatory mites Pesticides Diseases: Dithane (mancozeb), Amistar (azoxystrobin), Acrobat (dimethomorph, mancozeb), Signum (pyraclostrobin, boscalid) Thrips: Karate (lambda-cyhalothrin) l [no insecticides id for onion flies] Analyses Disease incidence in leaves and onions (also after storage), death/withering caused by onion flies, nutrient content in leaves/roots at vegetative stages, mycorrhiza colonization, nutrient t and vitamin i content t in onions, % onion fly infested onions, yield quantity and quality

14 WP4 Lettuce Lettuce, planted week 32 (~ 9 th August), harvest week 41 Biocontrol, diseases Mycorrhiza inoculation prior to planting; B. subtilis as foliar spray Biocontrol, pests Flower strips, releases of lady beetles and parasitoids Pesticides Amistar, Aliette (fosetyl), Revus (mandipropamid) against downy mildew Mospilan (acetamiprid), Movento (spirotetramat) against aphids Scoring Disease incidence in leaves, nutrient content in leaves/roots at vegetative stages, mycorrhiza colonization, nutrient and vitamin content in harvested heads, changes in aphid density, % aphid infested heads, yield quantity and quality

15 Thank you for your attention