Vol.:(0123456789) 1 3 Journal of Plant Diseases and Protection https://doi.org/10.1007/s41348-020-00362-6 ORIGINAL ARTICLE Efect of broomrape (Orobanche cumana Wallr.) on some agro‑morphological and biochemical traits of Tunisian and some reference sunfower (Helianthus annuus L.) accessions Taoufk Hosni 1,2  · Zouhaier Abbes 1  · Leila Abaza 3  · Sana Medimagh 1  · Hamadi Ben Salah 1  · Mohamed Kharrat 1 Received: 16 April 2020 / Accepted: 25 July 2020 © Deutsche Phytomedizinische Gesellschaft 2020 Abstract Orobanche cumana Wallr. is an important new problem for sunfower crop in Tunisia. Little information is available on the behavior of sunfower to O. cumana infestation in this region. Research activities are focusing on screening some sunfower accessions in order to identify resistant ones and to develop other cultural and biological methods to use them in integrated way to reduce the impact of this parasite. For this purpose, feld natural infestation and artifcial inoculation in pots and Petri dishes evaluations were conducted using eleven sunfower accessions out of them 4 introduced lines were known by their resistance to O. cumana used as reference. In infested feld, three of the reference lines (TL12, TL15 and TL16) did not show any emerged broomrape shoot and the values of their major agro-morphological parameters were not afected by parasit- ism. Results of pots and Petri dishes experiments confrmed the feld testing. In the resistant lines, the stems dry weight, the number and weight of sunfower seeds were not signifcantly reduced under infestation contrarily to the others accessions. The resistance of these lines is characterized by reduced germination percentage of Orobanche seeds and low attachments/ tubercles number of the parasite. O. cumana infection do not infuence seed oil content in resistant lines contrarily to sus- ceptible accessions. Nevertheless, no relationship was found between fatty acids composition and resistance to broomrape infestation. These results would be useful for improving resistance of sunfower against broomrape. Keywords Sunfower · Orobanche cumana · Oil · Fatty acids · Agro-morphological traits · Resistance Introduction Sunfower (Helianthus annuus L.) is an important oilseed crop in several countries of the world. A total of 26.67 mil- lion ha was cropped in the world in 2018, with a production of 51.95 million tons (FAOSTAT 2018). Sunfower seeds have a high quality vegetable oil which contains high level of unsaturated fatty acid, such as linoleic and oleic acid (Cucci et al. 2007). In addition, the sunfower meal is considered among the best for animal feed because of its high protein content (Morel et al. 2016). However, the production of sunfower sufers considerable decrease due to the negative impact of abiotic and biotic factors (Seiler et al. 2017). Now- adays, the parasitic plant Orobanche cumana Wallr. is con- sidered as the most important biotic constraint to sunfower production. The broomrape is an obligate root parasite com- pletely devoid of chlorophyll. Thus, it exhausts all nutrients and water from the roots of host plant, and causes severe damage to some feld crops. As O. cumana is difcult to be controlled mainly due to its high fecundity, the long-term viability of its seed in the soil and the appearance of new races of this parasite that overcome all the resistance genes in the cultivated sunfower (Masliiov et al. 2018), it is con- sidered as serious emerging problem. In fact, it has become a major threat to the sustainability of the sunfower crop in many areas in the world such as in countries around the Black Sea, Mediterranean Basin, Eastern Europe, Southeast- ern Europe, Middle-East and Asia (Mohamed et al. 2006; Molinero-Ruiz et al. 2015). * Taoufk Hosni hosnitaoufk@hotmail.fr 1 Laboratory of Field Crops, National Institute for Agricultural Research of Tunisia (INRAT), Carthage University, Hedi Karray Street, 1004 El Menzah, Ariana, Tunisia 2 Faculty of Science of Bizerte, Carthage University, 7021 Jarzouna, Bizerte, Tunisia 3 Laboratory of Olive Tree Biotechnology, Centre of Biotechnology of Borj-Cedria (CBBC), B.P. 901, 2050 Hammam-Lif, Tunisia