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Broomrapes (Orobanche spp.) are phanerogamic holoparasites that subsist upon the roots of many important crops thus causing considerable yield losses, especially in the drier and warmer areas of Europe, Africa and Asia. The major principles of reducing the seed bank and controlling the weed in the germination and parasitic/ reproductive phases are critically reviewed. Practices to control broomrape include physical methods (weeding, soil tillage, flooding, irrigation, solarization, flaming), chemical methods (soil fumigation, herbicide application, use of germination stimulants) and biological methods (use of resistant or tolerant varieties, cropping systems with trap and catch crops, intercropping, biological control with insects or fungi). Cultural practices which help to avoid germination, infection or strong reproduction of the weed or improve the crop's tolerance should be optimized. However, no single cheap method can control the weed, so integrated management practices are required. Integrated control strategies are site‐ and cropping‐system specific but have in common that measures are taken to kill part of the seed bank, induce the conditioned seeds to germinate in the absence of the commercial crop, kill emerging Orobanche shoots before seed set during growth of the commercial crop and further reduce or avoid damage to the commercial crop.

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Seven series of laboratory and glasshouse experiments were conducted to investigate different methods of testing and studying the effect of several chemicals, root exudates of germinating crop seeds, and their interactions on Orobanche cernua. Compared to experiments in an incubator, better results were obtained when seed germination was tested in the presence of seedlings of host plants under glasshouse conditions. GR24 at 0.1 and 1.0 mg kg-1 was the most effective in stimulating the germination of O. cernua seeds, followed by gibberellic acid at 10 and 20 mg kg-1. Without the addition of chemicals, trap crops strongly increased germination, with green gram (Vigna radiata) and sunn hemp (Crotalaria juncea) being particularly effective. There was an interaction between the effects of chemicals and trap crops. A positive effect of trap crops was observed even when there was already strong stimulation by GR24 at 1.0 mg kg-1, but under these conditions, trap crops were less effective at 0.1 mg kg-1 GR24. No differences between cultivars in their effect on O. cernua germination could be detected within one host plant species.