Abstract: Disclosed are methods for increasing infectivity of entomopathogenic nematodes in any target area for the purposes of insect control, said method comprising: (a) mixing an aqueous nematode infectivity increasing composition with (i) entomopathogenic nematodes to activate said entomopathogenic nematodes for increased infectivity prior to application of said entomopathogenic nematodes to said target area, or (ii) seeds to produce coated seeds, and (b) applying said entomopathogenic nematodes to said target area or planting said coated seeds in said target area; wherein said aqueous nematode infectivity increasing composition is produced by methods disclosed herein.

Abstract: Plant parasitic nematodes prefer to infect uninfected over infected hosts. A specific mixture of pheromones (a.k.a. ascarosides) tells plant parasitic nematodes the host status. We use a mixture of pheromones to direct nematodes away from the healthy roots. The pheromone mixture will be used for seed treatments to protect plant roots from infection by telling the nematodes that the plant is already infested and that they should move away and find new hosts. Chemical synthesis of pheromones is expensive, particularly when it is contains multiple compounds. Therefore, we obtained a partial mixture from Steinernema growth medium which provided 15% more directional movement away from the application site. We complete the necessary pheromone from the growth medium of Heterorabditis species to direct nematodes away from the seeds and roots of healthy plants. The pheromone mixture will be used to in the irrigation water or seed treatment to direct the plant parasitic nematodes away from the plant roots.

Abstract: Nematode dispersal is one of the key features for success as a biocontrol agent. Currently, commercially available nematodes do not disperse sufficiently when they are applied to a field. Since the insect target is mobile, nematodes need to be actively moving and seeking an insect host. We developed a pheromone extract from nematode growth medium that disperses nematodes. This extract was unstable in liquid form. We have found that the extract can be dried to retain activity during storage or shipment. Exposing nematodes to pheromone extract before they are applied to a field activates them to disperse and seek a new host. This exposure needs to be at least 20 min. When nematodes are actively seeking a new host this increases nematode insect encounter and increases insect mortality leading to increased effectiveness of insect nematodes as biological control agents.