Tolerant varieties are able to endure infection with minor losses on productivity. On the contrary, weedy broomrape species are usually generalists attacking annual crops (Schneeweiss, 2007). Host plant resistance to parasitic weeds; recent progress and bottlenecks. It is a prolific seed producer. 37, 3751. Once in the parasite system, sucrose is not accumulated but metabolized to other compounds. Please enable it to take advantage of the complete set of features! Crop Prot. doi: 10.1017/S0960258500002671, Lpez-Bellido, R. J., Bentez-Vega, J., and Lpez-Bellido, L. (2009). Fig. Genetic Diversity of Orobanche cumana Populations in Serbia. (2007). Possible involvement of gibberellins and ethylene in Orobanche ramosa germination. Isr. why is closed source software compiled broomrape and bursage relationship. As the tubercle matures a crown of adventitious roots will emerge from this tubercle carrying capacity of developing lateral haustorial connections. Those mechanisms kill the broomrape either by inducing toxic effects or by starving the parasite. (2002). doi: 10.1007/s11248-004-7546-1, Harb, A. M., Hameed, K. M., and Shibli, R. A. Hanson is part of a team of UC researchers enlisted by the processing tomato sector to work on a plan to contain the damage caused by branched broomrape, should it become established enough that the California Department of Food and Agriculture zero-tolerance quarantine strategy is replaced by management programs. Multiple flushes (cohorts) of emergence could be found within a single season . Keywords: by . Tetrahedron Lett. 65, 453459. 13, 478484. The use of several phytopathogenic fungi for broomrape control. Haustorium 53, 13. Crop Prot. In general, parasitized crops suffer from reductions in total biomass at the greatest expense to the reproductive tissue (Barker et al., 1996; Manschadi et al., 1996; Lins et al., 2007). doi: 10.1021/jf030025s, Grenz, J. H., Manschadi, A. M., Uygurc, F. N., and Sauerborn, J. Therefore broomrape seeds timely gain sensitivity for host chemodetection by means of conditioning (Lpez-Granados and Garca-Torres, 1996). This site needs JavaScript to work properly. Hamamouch, N., Westwood, J. H., Banner, I., Cramer, C. L., Gepstein, S., and Aly, R. (2005). If this effect is confirmed, L-methionine use to elicit resistance to broomrape in susceptible crops could be a straightforward strategy either by direct applications of this amino acid in the soil as explained in Section Control Strategies Targeting Host Penetration or delivered by overproducing and excreting microorganisms as explained in Section Strategies to Control Underground Broomrapes Acting after Establishment.. For instance, tori (Brassica campestris var. Parasitic plants Striga and Phelipanche dependent upon exogenous strigolactones for germination have retained genes for strigolactone biosynthesis. doi: 10.1080/09670870050206019, van Hezewijk, M. J., and Verkleij, J. The parasitic plant genome project: new tools for understanding the biology of Orobanche and Striga. The haustorium and the life cycles of parasitic Orobanchaceae, in Parasitic Orobanchaceae, eds D. M. Joel, J. Gressel, and L. J. Musselman (Heidelberg: Springer Berlin), 2123. Inhibition of Orobanche crenata seed germination and radicle growth by allelochemicals identified in cereals. Weed Sci. doi: 10.1093/aob/mcr261, Joel, D. M., Chaudhuri, S. K., Plakhine, D., Ziadna, H., and Steffens, J. C. (2011). A variety of methods have been developed to specifically neutralize broomrape pre-attached development though the majority of them are not commercially implemented because they are still at the stage of development or have not proved enough efficiency or applicability for large scale crops. They elicit GA-like germination activity in dormant seeds of several autotrophic plant species (Suttle and Schreiner, 1982; Metzger, 1983), constituting a cheap alternative to natural bioregulators for weed seed bank control (Suttle, 1983). Control the Striga conundrum. Phthalimide-lactones stimulate germination of parasitic weeds, in Proceedings of the XXXV Biennial Meeting of the Spanish Royal Society of Chemistry, eds J. J. Agric. In recent years, a new, aggressive race designated as race F (called biotype D in Russia) has . Ann. Metabolites. Main drivers of broomrape regulation. A review | SpringerLink Biological regulation of broomrapes. based on a life cycle model. Such target-site resistance is also available in other broomrape-susceptible crops but remains to be tested and registered to control broomrape. Plant Microbe Interact. The first step of conditioning promotes in the parasitic seed receptors the required sensitivity for the second step of host detection (Musselman, 1980; Kebreab and Murdoch, 1999; Lechat et al., 2012, 2015; Murdoch and Kebreab, 2013). Orobanche crenata in Sudan: history, distribution and management. Technol. doi: 10.1046/j.1365-3180.1998.00105.x, Hibberd, J. M., Quick, W. P., Press, M. C., and Scholes, J. D. (1998). Plant Dis. Figure 1. Branched broomrape has recently been detected in isolated fields in Yolo, Solano and San Joaquin counties, but the processing tomato business has a history of investing in efforts to eradicate this potentially disastrous weed. Hemp broomrape (Orobanche ramosa), also known as branched broomrape, is a noxious pest around the world and can cause significant losses if crops are heavily infested. Nitrogen metabolism remains largely unknown in broomrape. doi: 10.1093/aob/mcm032, Ben-Hod, G., Losner-Goshen, D., Joel, D. M., and Mayer, A. M. (1993). Aber M., Fer A., Salle G. (1983). For instance, root exudates of field pea induces high germination of the very destructive broomrape species O. crenata, O. foetida, O. minor, and P. aegyptiaca, however, it only becomes infected by O. crenata therefore pea may theoretically be a good trap crop against O. foetida, O. minor, and P. aegyptiaca but not for O. crenata infested field (Fernndez-Aparicio and Rubiales, 2012). Field Crops Res. Due to the high broomrape fecundity, long seed viability and for some weedy broomrape species, broad host range, the seed bank is easily replenished and long lasting. Biology and management of weedy root parasites. The papillae form a crown around the apical cells that remain non-papillate but later will become intrusive cells with an essential function in the penetration process. For example, soil application of uniconazole, a triazole that is commercially used for growth regulation has proved to reduce parasitism by inhibiting seed conditioning and subsequent germination (Joel, 2000; Zehhar et al., 2002; Song et al., 2005; Lechat et al., 2012). broomrape and bursage relationship - 1atlanticfunding.com Orobanchaceae - the parasitic Broomrape family Depending on the genetic background of the resistant host, the intrusive cells of broomrape seedling can be stopped at three different levels in their way of penetration through the root layers to achieve connection with the host vascular system. Weed Sci. Joel, D. M. (2013). orthoceras, a potential mycoherbicide, parasitizes seeds of Orobanche cumana (Sunflower broomrape): a cytological study. Am. 44, 22212229. in faba bean (Vicia faba) based in low induction of broomrape seed germination. Until now, difficulties of purification at industrial scale have hampered the field experimentation with such metabolites (Vurro et al., 2009) despite their interesting potential. Azospirillum brasilense is reported to inhibit broomrape radicle growth (Dadon et al., 2004). In vitro treatments of a large range of sulfonylurea herbicides inhibit broomrape germination and radicle elongation (Hershenhorn et al., 1998; Plakhine et al., 2001). (2006). (2004). doi: 10.1021/jf991145w, Panetta, F. D., and Lawes, R. (2005). 35, 445452. Nat. Prez-Vich, B., Velasco, L., Rich, P. J., and Ejeta, G. (2013). Phosphorus deficiency in red clover promotes exudation of orobanchol, the signal for mycorrhizal symbionts and germination stimulant for root parasites. Molecular responses of Lotus japonicus to parasitism by the compatible species Orobanche aegyptiaca and the incompatible species Striga hermonthica. 2022 Nov 29;12(12):1195. doi: 10.3390/metabo12121195. Nitrogen and carbon relationships between the parasitic weed Orobanche foetida and susceptible and tolerant faba bean lines. The biological activity of AC-94, 377 [1-(3-chlorophthalimido)-cyclohexane-arboxamide]. doi: 10.1007/s11627-007-9054-5, Aly, R., Plakhin, D., and Achdari, G. (2006). Pest Manag. Seed Sci. This technique promotes the host plant to fulfill its required thermal time to flower in a shorter number of days, making the grain filling period shorter. We want to time the application to when the broomrape attaches to the tomato roots.. (2005). Copyright 2016 Fernndez-Aparicio, Reboud and Gibot-Leclerc. broomrape, (genus Orobanche), genus of about 150 species of parasitic annual or perennial herbs (family Orobanchaceae). First report of crenate broomrape (Orobanche crenata) on lentil (Lens culinaris) and common vetch (Vicia sativa) in Salamanca Province, Spain. Please refer to the appropriate style manual or other sources if you have any questions. Maintenance of relative low levels of those amino acids in tubercles either by low levels of synthetase activities (McNally et al., 1983) and or their rapid turnover of host-derived amino acids, establishes a decreasing concentration gradient that favors the unloading of amino acids into the parasite (Abbes et al., 2009). -, Abbes Z., Kharrat M., Delavault P., Chabi W., Simier P. (2009). These thumbnail pictures have links to larger photographs and . PLoS ONE 7:e49273. J. Agric. Biol. Crop Prot. Israeli researchers developed a temperature/moisture model for application of low rates of an ALS inhibitor on processing tomatoes. This is how can we live with this without huge yield losses. doi: 10.1111/j.1365-3180.2010.00771.x, Fernndez-Aparicio, M., Flores, F., and Rubiales, D. (2009a). July 4, 2022 July 4, 2022. Weed Sci. 155, 728734. The new nomenclature of Orobanche and Phelipanche. The physiology of the established parasite-host association, in Parasitic Orobanchaceae, eds D. M. Joel, J. Gressel, and L. J. Musselman (Berlin: Springer), 87114. Being deprived of the initiation of autotrophic mode of life, the growth of broomrape seedling toward the host is only sustained by water absorption and remobilization of reserve nutrients from the seed perisperm and endosperm (Joel, 2000; Joel et al., 2012). Weed Sci. doi: 10.1016/j.biocontrol.2003.12.003. Rev. Ann. Ann. excrete enzymes with carbohydrase activity. The timing of herbicide application is essential.. Management of Infection by Parasitic Weeds: A Review. PDF 7 K H Uh Od Wlr Q V K Ls E H Wz H H Q Wh P S H Ud Wx Uh D Q G V P D Oo Therefore an integrated and sustained management strategy composed by several control methods acting at different broomrape life stages is highly recommended to keep away the broomrape weed problem in a durable manner (Kebreab and Murdoch, 2001). These stages constitute sites of broomrape metabolism at which it is possible to design successful strategies to inhibit its sophisticated parasitism. Technologies for smart chemical control of broomrape (Orobanche spp. 25, 803813. Would you like email updates of new search results? The flower shoots are scaly, with a dense terminal inflorescence (spike) of 10-20 flowers in most species. Zhang, Y., Luc, J. E., and Crow, W. T. (2010). Intercropping with cereals reduces infection by Orobanche crenata in legumes. First, broomrape weeds are achlorophyllous and therefore those herbicides that target photosynthetic process, e.g., triazines or substituted urease [C group in the Herbicide Resistance Action Committee (HRAC) classification], will have only limited effect on broomrapes. The effect of nitrogenous compounds on in vitro germination of Orobanche crenata Forsk. Ann. Plant Physiol. 12, 638652. Omissions? Keyes, W. J., OMalley, R. C., Kim, D., and Lynn, D. G. (2000). doi: 10.1093/jxb/34.5.610. GA acts positively on germination in dormant non-parasitic species by counteracting ABA (Seo et al., 2009). High osmotic potential in roots and drop in amino acid levels in the phloem has been reported in tolerant varieties of faba bean in response to broomrape parasitism. It is not difficult to imagine many cases in which parents could be motivated to experiment with such biotechnology in an effort to control a child's loving feelings. J. Linn. Thorie Elmentaire de la Botanique. The Broomrape takes its food, nutrients, and water from the roots of the Bursage which weakens the Bursage. This resistance is coordinated with the expression of genes encoding for pathogenesis-related proteins (Sarosh et al., 2005; Hasabi et al., 2014). Sci. Phytopathol. Mller-Stver, D. (2001). Transfer of organic substances from the host plant Vicia faba to the parasite Orobanche crenata Forsk. Soyasapogenol B and trans-22-dehydrocamposterol from common vetch (Vicia sativa L.) root exudates stimulate broomrape seed germination. broomrape and bursage relationship. The opposite agricultural practice deep-plowing, has been suggested to bring seeds of parasitic weeds to a depth with less oxygen availability and therefore a reduction in its germination capacity (Van Delft et al., 2000). Agronomie 21, 757765. The consequent reduced flux of water and nutrients toward the parasite, low utilization of host-derived sucrose and lower levels of soluble proteins limits the parasitic sink strength and yield losses due to broomrape parasitism (Abbes et al., 2009). Bethesda, MD 20894, Web Policies (2012). Fenugreek root exudates show species-specific stimulation of Orobanche seed germination. 28 Articles, This article is part of the Research Topic, Specialized Mechanisms in Broomrape Weeds for a Parasitic Mode of Life, Control Strategies Targeting Underground Broomrape Stages, http://www.terresinovia.fr/orobanche/carte.php, www.fao.org/ag/AGP/AGPP/IPM/Weeds/Issues/orobanche.htm, www.epa.gov/opprd001/inerts_list4Bname.pdf, Creative Commons Attribution License (CC BY). 2022 Mar 23;13:733116. doi: 10.3389/fpls.2022.733116. Fernndez-Aparicio M, Masi M, Cimmino A, Evidente A. doi: 10.1093/pcp/pcr031, Nandula, V. K., Foster, J. G., and Foy, C. L. (2000). List of Inert Pesticide Ingredients List 4b. Thats what the Israelis do; they went from 70 percent yield losses to very modest losses they can live with.. 60, 641650. (2009). The Flower That Must Not Be Named - The New York Times Recent approaches for chemical control of broomrape (Orobanche spp.) FOIA B., Delavault P., Chaibi W., Simier P. (2010). 41, 127151. doi: 10.1111/j.1365-3180.2007.00583.x, Mabrouk, Y., Zourgui, L., Sifi, B., Delavault, P., Simier, P., and Belhadj, O. Induction of phenolic compounds in pea (Pisum sativum L.) inoculated by Rhizobium leguminosarum and infected with Orobanche crenata. Their absolute dependence on host-derived nutritive resources for successful seedling establishment and consequent growth makes necessary the synchronization of parasitic germination with the growth of its host. Systemic acquired resistance in crop protection: from nature to chemical approach. PDF Red Rock Relationships - Bureau of Land Management Technol. Weed Res. Lpez-Rez, J. The Biology of Parasitic Fowering Plants. The best studied group of germination-inducing factors are strigolactones, a group of terpenoid lactones. Figure 1. doi: 10.1111/j.1365-3180.2009.00748.x. Ann. Nutrient effects on parasitism and germination of Egyptian broomrape (Orobanche aegyptiaca). Fernndez-Aparicio, M., Soto, M. J., Rubiales, D., Ocampo, J. Another strategy to induce suicidal germination of broomrape seed bank could be the use of gibberellin agonists. doi: 10.1007/s00425-006-0410-1, Zehhar, N., Ingouff, M., Bouya, D., and Fer, A. Flowchart showing major underground parasitic events developed by broomrape weeds on susceptible crops and the control strategies that successfully target them. Role of the sucrose synthase encoding PrSus1 gene in the development of the parasitic plant Phelipanche ramosa L. (Pomel). The parasitic weed radicle that emerges from germinated seed and carries the attachment organ is also targeted by those mycoherbicides (Abbasher and Sauerborn, 1992). Biotic inducers of systemic resistance have also proved being successful against broomrape parasitism under experimental conditions. 42, 5760. A., and Rubiales, D. (2010a). Bot. 2021 Dec;37(6):512-520. doi: 10.5423/PPJ.OA.04.2021.0066. doi: 10.1139/B10-057, Lechat, M. M., Brun, G., Montiel, G., Veronesi, C., Simier, P., Thoiron, S., et al. Botany 88, 839849. Cell wall-degrading enzyme in Orobanche aegyptiaca and its host Brassica campestris. (2002). Weed Res. Resistance and avoidance against Orobanche crenata in pea (Pisum spp.) PDF BSA-seq mapping reveals major QTL for broomrape resistance in four PPT - Symbiosis PowerPoint presentation | free to download - id: 57c2dc Ambio 35, 281288. Ann. (2001). Emerged small broomrape stalks in a red clover seed production eld. Inhibition of seed conditioning and subsequent germination mediated by inhibitors of GA synthesis reduces the receptivity of broomrape seeds to germination-inducing factors. seed germination and radicle growth. Strigolactone analogs derived from ketones using a working model for germination stimulants as a blueprint. Isr. (2015). Orobanche crenata in Ethiopia. Resistance against broomrapes (Orobanche and Phelipanche spp.) Rev. 42, 464469. Joel, D. M., Back, A., Kleifeld, Y., and Gepstein, S. (1991). doi: 10.1006/anbo.1998.0847, Toh, S., Kamiya, Y., Kawakami, N., Nambara, E., McCourt, P., and Tsuchiya, Y. doi: 10.1111/j.1365-3180.2009.00742.x, Rubiales, D., Fernandez-Aparicio, M., and Rodriguez, M. J. The activity of glutamine synthetase in broomrape is very low and therefore carries a reduced broomrape ability to detoxify ammonium. The broomrape radicle shows no gravitropism and grows toward the host as a result of cell elongation. 65, 560565. Were trying to get a relatively low rate of material into the crop, high enough to kill the parasitic weed but low enough to not damage the crop, Hanson said. Food Chem. doi: 10.1017/S0960258510000371, Fernndez-Aparicio, M., Cimmino, A., Evidente, A., and Rubiales, D. (2013). 31, 2730. PDF Broomrape research update - ucanr.edu J. Careers. Bot. doi: 10.1006/anbo.1998.0629, Johnson, A. W., Rosebery, G., and Parker, C. (1976). J. Interestingly, experimentation carried out on broomrape species specialized on summer crops revealed their lower requirement for conditioning when compared with species specialized in winter annual crops highlighting the ecological adaptation of broomrape weeds to the cropping system in which they become specialized (Plakhine et al., 2009). 2021 Feb 5;2(5):100166. doi: 10.1016/j.xplc.2021.100166. Broomrape attack is more severe on crops growing in low fertility soils. Multiple KAI2d genes across broomrape species genomes may allow diversified recognition of root exudates corresponding with suitable hosts (Conn et al., 2015). The broomrapes are obligate plant-parasitic plants from the genera Orobanche and Phelipanche in the Orobanchaceae family (Bennett and Mathews, 2006; Tank et al., 2006; Joel, 2009). Available at: www.fao.org/ag/AGP/AGPP/IPM/Weeds/Issues/orobanche.htm, Acharya, B. D., Khattri, B. G., Chettri, M. K., and Srivastava, X. 2. This would open the work on parasitism toward more community ecology and what can be considered the realistic nature of parasitism. However, the overall productivity of the host-parasite system is also reduced due to the shorter growing period being detrimental for crop yield. S. J. Ter Borg (Wageningen: LH/VPO), 2534. Broomrape seed bank presents annual cycles of non-deep physiological dormancy induced by seasonal changes in climatic conditions. Effect of amino acid application on induced resistance against citrus canker disease in lime plants. J. Unauthorized use of these marks is strictly prohibited. broomrape and bursage relationship. Resistance of red clover (Trifolium pratense) to the root parasitic plant Orobanche minor is activated by salicylate but not by jasmonate. doi: 10.1002/ps.1742, Vurro, M., Boari, A., Pilgeram, A. L., and Sands, D. C. (2006). Group 6, 1119. The following sections and Table 1 review the major feasible control measures for broomrape control. B., Delavault, P., Chaibi, W., and Simier, P. (2010). SA promotes resistance to broomrape. Host plant resistance against broomrapes (Orobanche spp. Phytoparasitica 31, 422. This work was cofunded by the European Union and INRA, in the framework of the Marie-Curie FP7 COFUND People Program, through the award of an AgreenSkills fellowship (under grant agreement n PCOFUND-GA-2010-267196) to MF-A with additional support by the INRA Division Sant des Plantes et Environnement., Abbasher, A. Lins, R. D., Colquhoun, J. Induced resistance an innovative approach to manage branched broomrape (Orobanche ramosa) in hemp and tobacco. Sci. Many other interesting examples of trap crops emerged from a root exudates screening of important crops (Fernndez-Aparicio et al., 2009b). Eizenberg, H., Aly, R., and Cohen, Y. Therefore, decisions on the date of sowing has to be well-adjusted in order to balance the loss of productivity due to shorter growing period with gain of productivity due to reduced parasitism. (1969). 48, 93117. (2012). Plant Sci. Lpez-Granados, F., and Garca-Torres, L. (1996). Because parasitic weeds require host encoded molecules to stimulate the initiation of parasitism both at the level of seed germination and haustorium initiation, breeding for low-inducers genotypes of those processes are obvious targets for resistance (Yoder and Scholes, 2010). Intercropping systems cultivate simultaneously more than one species in close association to take agronomic advantage of biodiversity, competition, and complementarity between them. Rubiales, D., Alcntara, C., Prez-de-Luque, A., Gil, J., and Sillero, J. C. (2003a). Breeding approaches for crenate broomrape (Orobanche crenata Forsk.) doi: 10.1093/aob/mcn236. doi: 10.1080/09583159929857. B., Thoiron, S., Leduc, N., et al. doi: 10.1023/B:GROW.0000038242.77309.73, Goldwasser, Y., Kleifeld, Y., Golan, S., Bargutti, A., and Rubin, B. Abbes Z., Kharrat M., Pouvreau J. doi: 10.1007/BF00029536, Tan, S., Evans, R. R., Dahmer, M. L., Sing, B. K., and Shaner, D. (2005). Aber, M., Fer, A., and Salle, G. (1983). Weed Res. Rhizobium leguminosarum induces defense mechanisms based on elevated induction of the phenylpropanoid pathway conferring mechanical and chemical barriers to the parasite penetration (Mabrouk et al., 2007a,b,c, 2010). Sauerborn, J. Biocontrol Sci. Solute fluxes from tobacco to the parasitic angiosperm Orobanche cernua and the influence of infection on host carbon and nitrogen relations. Bot. 1, 139146. Broomrapes are plant-parasitic weeds which constitute one of the most difficult-to-control of all biotic constraints that affect crops in Mediterranean, central and eastern Europe, and Asia. A number of broomrape species are serious agricultural threats. Plant. 18, 463489. Broomrape management elsewhere Israeli cooperators have been working on broomrape management for several decades Eizenberg, Goldwasser, and others Weed is not eradicated, but is managed to an acceptable level Management is based on carefully -timed and -placed herbicides to disrupt key broomrape life stages The development of mycoherbicides for the management of parasitic weeds of the genus Striga and Orobanchea review and recent results, in Proceedings of the X International Symposium on Biological Control of Weeds, ed. 48, 39303934. 6, 143. Title: Symbiosis Author: MPS Last modified by: M Created Date: 2/15/2006 2:48:56 PM Document presentation format: On-screen Show Company: MUS Other titles - A free PowerPoint PPT presentation (displayed as an HTML5 slide show) on PowerShow.com - id: 57c2dc-ODc5Z 56, 574581. 16, 153160. (2012). 3585999. doi: 10.1111/j.1439-0434.2007.01307.x, Mabrouk, Y., Simier, P., Delavault, P., Delgrange, S., Sifi, B., Zourgui, L., et al. Broomrape seeds are less capable to recognize crop roots colonized by arbuscular mycorrhizal fungi, Rhizobium leguminosarum or Azospirillum brasilense due to change in the composition of the root exudates in colonized plants (Dadon et al., 2004; Mabrouk et al., 2007a; Fernndez-Aparicio et al., 2009c, 2010b; Louarn et al., 2012). 6, 269275. doi: 10.1007/s10658-004-2814-8. Correlated evolution of life history and host range in the nonphotosynthetic parasitic flowering plants Orobanche and Phelipanche (Orobanchaceae). Biol. Plant Cell Physiol. doi: 10.1111/j.1365-313X.2007.03171.x, Klein, O., and Kroschel, J. 79, 463472. (2005). (2012). However, exogenous application of GA alone is not sufficient to promote broomrape germination (Takeuchi et al., 1995; Chae et al., 2004) and strigolactone-mediated ABA catabolism in conditioned seeds is required to trigger germination (Lechat et al., 2012). doi: 10.1111/j.1366-9516.2005.00179.x, Parker, C. (2009). Lack of knowledge in the molecular regulation of the host-parasite interaction during crop invasion has impeded the development of varieties carrying transgenes with capacity to inhibit broomrape penetration. Broomrape species display high diversity with regard to their host range. Increasing control reliability of Orobanche cumana through integration of a biocontrol agent with a resistance-inducing chemical. Interactions between the parasitic angiosperm Orobanche aegyptiaca and its tomato host: growth and biomass allocation. Nat. This surface is covered by carbohydrate secretion that sticks the haustorium to the host surface. Plant 43, 304317. The first mechanism involved in host specialization is displayed during broomrape germination and is mediated by the broomrape recognition of host root exudates in a species-specific manner. Plant Growth Regul. doi: 10.1146/annurev.pp.30.060179.002533. Influence of soil moisture on activity and persistence of the strigol analogue GR 24. The broomrape plant is small, from 10-60 cm tall depending on species. doi: 10.1016/S0378-4290(00)00089-7, Gibot-Leclerc, S., Abdennebi-Abdemessed, N., Reibel, C., and Colbach, N. (2013). Persistence of GR7 and Striga germination stimulant(s) from Euphorbia aegyptiaca Boiss.