The effect of pro-ecological procedures and plant injury on the content of free phenolic acids in winter wheat and on the feeding and development of Oulema melanopus

Under laboratory conditions we have investigated the effect of the application of pro-ecological procedures (effective microorganisms and biostimulant Asahi SL) and plant injury on the production of free phenolic acids in winter wheat and on the feeding and development of Oulema melanopus. Wheat plants before reaching the BBCH 32 stage (the beginning of stem elongation) were treated with effective microorganisms and the biostimulant Asahi SL. Then, for 2 days, some of the plants were injured by O. melanopus and some were uninjured. The influence of factors was investigated in conditions under which the cereal leaf beetle had the possibility to choose their food (no-choice test or choice test). It was found that wheat plants produce on average 0.172% DM of free phenolic acids. It has been shown that O. melanopus males and females preferred wheat previously uninjured. Also, irrespective of whether the plants were previously injured or uninjured, the females of that pest species always that caused areally more extensive leaf losses than the males. Treating plants with effective microorganisms and biostimulant Asahi SL is a secondary factor, as compared to previous wheat injury. Additionally, in choice tests, both males and females O. melanopus much preferred feeding on plants unprovided with preparations, whereas in no-choice tests, the application of pro-ecological procedures does not reduce egg laying by pests, does not adversely affect embryogenesis length and does not reduce hatching L1.