The present invention relates to a method of cultivating, in medium, Steinernema kushidai (hereinafter simply called kushidai) which is one type of Nematoda. Kushidai has a strong insecticidal ability to kill larvae of coliopterous insects, and cultivation of large quantities of kushidai having the strong insecticidal ability requires conditions different from the techniques of cultivating other nematodes parasitic on insects. Kushidai is cultivated in a medium including asteroid. This increases the insecticidal activity with respect to insects harmful to plants such as crops. The medium including asteroid may be adsorbed to a plurality of supports, and then the supports may be stacked with gaps thereamong to form a layer. This enables kushidai to be cultivated efficiently. Further, a liquid medium including asteroid may be prepared, with cultivation carried out while agitating the medium and supplying oxygen thereto. This obtains kushidai having a high multiplication characteristic and high insecticidal activity. The kushidai is used as a biological agrochemical to reduce damage done to crops such as sweet potato by harmful insects.
Disclosed are an apparatus and methods for in vivo mass production of insecticidal nematodes, which the efficiency and volume of nematode production. In the method, nematodes are cultured within a natural insect host. The apparatus comprises at least one harvesting area, a water dispensing system that promotes harvest of nematodes from the host organisms, and a water collection and concentration system for nematode collection and storage. The harvesting area comprises reusable stackable perforated trays, which allow passage of dispensed water while retaining the nematode hosts. The perforations are sized to retain the host organisms and facilitate the passage of harvested nematodes carried within the dispensed water.
