Efficiency of entomopathogenic nematodes on chamomile smooth beetle Olibrus aeneus and chamomile stem weevil Microplontus rugulosus under greenhouse conditions

Chamomile Matricaria recutita (L) is an ancient healing plant; it is used for a sore stomach, a mild laxative, anti-inflammatory and a gentle sleep aid. Chamomile plants are infected by many insect pests. The flower heads are infested by chamomile smooth beetle Olibrus aeneus (Fabricius 1792). The dangerous insect is infestation with chamomile stem-weevil Microplontus rugulosus (Autumn 1795). Their infestations lead to a high reduction in chamomile yield. This work aimed to determine the adequate management strategies of Microplontus rugulosus and Olibrus aeneus, especially using entomopathogenic nematodes. Management of chamomile insects was conducted on plants moved from field to greenhouse using entomopathogenic nematodes; while the control plants were sprayed only with water. The efficiency of three types of entomopathogenic nematodes (EPNs) was evaluated; each strain replicated 3 times; each was 50 chamomile plants (totally is 150 for each strain). Three treatment dates were carried out in May, June and July; the first one was mainly for controlling stem weevil, while the other two dates were for smooth beetle. Steinernema carpocapsae had more efficiency than S. feltiae and Heterorhabditis bacteriophora. The lived larvae were higher in the untreated than treated plants. EPNS could be one of the most effective management strategies to control such insects to keep the environment clean and should be one of the suitable control strategies for integrated insect management practices which would be developed with the ecological requirements of insects in different chamomile fields.