Organic Pesticides

1. Organic Pesticides by: samantha snyder

2. Since I ‘retired’… • Raising chickens • KTOK 1000 AM • OSU-OKC • Horticulture Consulting www.okcgardentutor.com

3. Why talk about organics? • Lack of training on the topic • Available info is either limited or overwhelming • Personal interest

5. Digging through the dirt • There is information out there on everything • What to trust and recommend as ‘organic’

6. What does organic mean to you?

7. No chemicals… • No man-made chemicals… • Only plant derived products… • Homemade products…

9. Organic Materials Review Institute • Founded in 1997, the Organic Materials Review Institute (OMRI) provides organic certifiers, growers, manufacturers, and suppliers an independent review of products intended for use in certified organic production, handling, and processing. OMRI is a 501(c)3 nonprofit organization. When companies apply, OMRI reviews their products against the National Organic Standards. Acceptable products are OMRI Listed® and appear on the OMRI Products List.

11. Organic growers work in conjunction with Government Certifiers to maintain compliance with National Organic Standards. • OMRI is the ‘safe list’

12. Common Organic Pesticides • Bt or Bacillus thuringiensis • Copper • Neem • Pyrethrum • Oils

13. “Organic pesticides are safe for me and the evironment.” True or False?

14. “Organics are safe for me and the environment.” • False!!! • ‘safe’ • Signal Words????

15. Bt – “Caution” • Non Synthetic • AI- proteins produced by Bt bacteria • Spore forming bacteria • Common in terrestrial habitat • Soil, dead insects, plants, granaries

16. How Bt works • MUST be eaten by susceptible pest • Endotoxin binds to gut creating a hole/pore • Contents enter the body cavity/bloodstream • No immediate knock-down • But does slow feeding

17. Bt – know your Latin • Imperative to match subspecies with pest • Bt kurstaki – Lepidoptera • Bt tenebrionis – Coleoptera • Bt israliensis - Diptera

18. Residual Effect • Only a few days • Broken down by sunlight • Can be used with ‘stickers’ or UV blockers

19. Best control • Early detection • Proper application • Timing • Location • Pest compatibility

20. Other info • Resistance is a problem • CO Potato Beetle – No OMRI approved products available • 100 Bt microbial insecticides registered • Based on 4 subspecies • Very available, but… • Some may have inert ingredients that are NOT OMRI approved • Hybrid Bt’s – crosses of wild types (Dipel,Javelin) Also NOT OMRI approved • Bt corn/cotton, Not OMRI approved

21. The ‘green’ aspect of Bt • Humans – Gut structure completely different • Rapid UV breakdown • Wildlife • Fed to birds and fish – no adverse effects • Natural Enemies • Parasites and predators – not harmed directly, but loss of host site could be a problem • NonTargets • Other moths and butterflies

22. Copper Products – “Danger, Warning & Caution” • Mineral based fungicide/bactericide • Considered synthetic • Allowed • Fixed coppers – minimize accumulation in soil • Copper hydroxide, copper oxide • Copper sulfate • Terrestrial • Aquatic

23. How Copper works • Cu ions disrupt the functions of proteins after being absorbed into fungus or bacterium • ‘Non-specific denaturation of cellular proteins • Best absorbed by germinating fungal spore • Multiple applications typically necessary to protect new plant growth

24. Cu is more soluble (releases Cu ions) in low pH • If applied with water pH lower than 6 phototoxicity can occur • Bordeaux mixes are Copper Sulfate and hydrated lime to avoid this efffect

25. Efficacy • Listed on over 100 crop plants to control fungal and bacterial diseases • More effective on bacterial than fungal, but widely recommended for both. • Tomatoes, Pines, Algae

26. ‘Green’ Aspect • Small amounts of Cu are needed for plant and animal life. Excessive amounts are dangerous • Leaf persistance • Can remain for 1-2 weeks • Or until it is washed off (rain, irrigation)

27. Fate in water and soils • Because it is so soluble, leaches well • Also binds tightly to soil • So only leaches well in very sandy soils • Very high levels have been found in ag settings after only a few decades

28. Wildlife • Practically non-toxic to birds • Highly toxic to fish – especially in acid water • Bees – endangered by bordeaux mix • Poison to sheep and chickens • As soil levels build, soil life diminishes • Worms, Rhizobium bacteria, etc • Will also control all forms of Bt

29. Human aspect • “Vineyard sprayers experienced liver disease after 3-15 years of exposure to copper sulfate solution in Bordeaux mixture.” • Nasty stuff! • Vomiting normally triggered instantly, but acid conditions of stomach encourage absorption. • Be cautious!!!

30. Neem (caution, warning) • Non-synthetic botanical pesticide • Derived from the neem tree, Azadiracta indica • Native to southern Asia (sub-tropical/tropical) • Cure of all ailments • Used for centuries for medical, cosmetic and pesticidal purposes

31. Research • As early as 1920 • 1959 – German ento noticed that neem trees in the Sudan resisted an attack of migratory locust

32. How it’s made • Crushing neem tree seeds • Water or solvent such as alcohol to extract pesticidal constituents • Different extraction process leads to different amounts of chemical present • Efficacy of different products may vary • Neem cake is residual seed – used as fertilizer

33. How it works • AI – Azadirachtin, one of the more than 70 compounds produced by the neem tree • Acts as an IGR and anti-feedant and oviposition deterrent • Works by contact or ingestion • Prevents molting (inhibits ecdysone production) • Stops feeding – physiological effect • Egg laying – volatile compounds repel insects

34. General application guidelines • Multiple applications • Broken down by UV and washed off easily • Use on immature insects • Use on low populations • Works best under warm temperatures • Apply to transplants before planting • Systemic properties are better than foliar applications (drench)

35. ‘Green’ aspect • Breaks down within 100 hours of light or water – mix and use • Wildlife – relatively non-toxic • Natural enemies – little or no effect on adult beneficials • Relatively harmless to: bees, spiders, ladybeetles parasitoid wasps, and adult butterflies. • Suitable for IPM inclusion

36. ‘green’ continued • Non target organisms – generally nontoxic • Neem leaves added to the soil increased earthworm weight and survival • More research needed • Human effects – likely does not pose a significant risk • Irritation to mucous membranes from seed dust • Most studies done on azadirachtin – not entire neem product

37. Efficacy • Affect over 200 insect species • Whiteflies, thrips, leafminers, caterpillars aphids, scales, beetles, true bugs and mealybugs, squash bugs, etc. • Efficacy can vary on species

38. Oils (caution) • Synthetic and natural • AI – 3 types • Petroleum (mineral) • Fish • Plant • Petroleum has the most available info and has been developed the most

39. How it works • Pet Oils – control the egg stage by interfering with gas exchange or egg structure • Other stages, can block respiratory system or cuticle break down • Plant and fish probably similar • All oils could disrupt insect behavior – feeding,oviposition • Plant vectored virus control – stylet oil

40. Pests controlled • Soft bodied insects • Aphids, mites, thrips, whiteflies, mealybugs, psyllids • “the only widely used class of pesticides to which insects or mites have not developed resistance.” (Sams and Deyton 2002)

41. Phytotoxicity • Visible leaf damage or yield reduction • The slower the oil evaporates, the higher the risk of damage • Avoid application on humid days

42. ‘Green’ aspect • Pet oils used on plants are light weight and generally evaporate quickly. • Effects of vapors not known • Negligible ability to contaminate soil or groundwater • Plant and Fish oils not as volatile, but break down quickly by microbes • Unlikely to have any effect on wildlife or non target species

43. Natural enemies –Can kill beneficial mites and cause flare up in population • Humans – low toxicity to those applying, typically gone by time of harvest

44. Efficacy • Long history of dormant spray in fruit crops to control mites and scale • Less experience with vegetable crops • Generally found to be more effective when mixed or used in combination with another pesticide

45. Pyrethrum (caution) • Botanically derived • Non-synthetic • Powdered, dried flowerheads of the pyrethrum daisy chiefly, Chrysanthemum cinerariaefolium • Native to SW Asia, Kenya is leading producer then Australia

46. Rums and Roids • Pyrethroids are synthetic compounds • Mode of action is similar • But not OMRI approved

47. How it works • Fast acting contact poison that ‘knocks down’ susceptible insects • Effects nervous system • Repetitive nerve discharges • Left paralyzed by toxic effects • If dose is too low, some insects can recover

48. Synergists • Enhanced mortality • Adding a non-insecticidal chemical heightens response • Reduces ability to detoxify pyrethrum • PBO – piperonyl butoxide is common but not OMRI approved • Use care when shopping • Others are now adding oils

49. This may be one example of an oil synergist • Not sure if it is OMRI approved • Found at Horns

50. Application Tips • Broken down by both acid and alkaline solutions : do not mix with lime, sulfur or soap • Rapidly broken down by UV • Contact poison • Spray flying insects (cuc beetle) in early morning while less active and before bee activity