42, 292297. The differentiation of xylem elements in the parasite are under the control of polar auxin transport (Harb et al., 2004; Bar-Nun et al., 2008). doi: 10.1007/BF02980855, Prez-de-Luque, A., Moreno, M. T., and Rubiales, D. (2008). 4, 25702575. 33, 787793. Westwood, J. H., dePamphilis, C. W., Das, M., Fernndez-Aparicio, M., Honaas, L. A., Timko, M. P., et al. Mol. Imazamox application timing for small broomrape (Orobanche minor) control in red clover. Some compatible Rhizobium leguminosarum strains in peas decrease infections when parasitized by Orobanche crenata. This article was most recently revised and updated by, https://www.britannica.com/plant/broomrape, Illinois Wildflowers - One-Flowered Broomrape, University of California - Branched Broomrape. Paris: Dterville. This study evaluated the relationship between small broomrape devel-opment and temperature with red clover as a host plant. Mitochondrial DNA suggests at least 11 origins of parasitism in angiosperms and reveals genomic chimerism in parasitic plants. Broomrape species display high diversity with regard to their host range. Technol. (2011). July 4, 2022 July 4, 2022. For instance, tori (Brassica campestris var. If successful, these studies could develop a strategy to limit the damage from broomrape if it becomes established and the strict quarantine is lifted. Sources of natural resistance based on low exudation of germination-inducing factors exist in legumes and sunflower and are highly effective in inhibiting broomrape weed parasitism (Labrousse et al., 2001, 2004; Rubiales et al., 2003b, 2009a; Prez-de-Luque et al., 2005; Sillero et al., 2005; Abbes et al., 2010; Fernndez-Aparicio et al., 2012b, 2014). The first function of haustorium is as adhesion organ to host root surface mediated by a papillae cell layer; (E) adhesion to the root 3 days after germination induction; (F) upon vascular connection with the host, broomape initiates the development of the tubercle, the broomrape storage organ for host-derived nutrients. The broomrape seed bank efficiency to initiate parasitism can be reduced by incorporation to the soil of several pathogens able to infect preattached broomrape stages such as Fusarium sp. Refined formulations and encapsulations of fungal propagules increase efficacy in biocontrol by reducing desiccation or microbial competition (Amsellem et al., 1999; Quimby et al., 1999; Kroschel et al., 2000; Mller-Stver, 2001; Aybeke et al., 2015). Promotion of suicidal germination is the technique used to induce broomrape germination with synthetic molecules in the absence of a host to which broomrape can attach, a technique lethal for the parasite as the broomrape seedling is unable to acquire autotrophy. update on breeding for resistance to sunflower broomrape / actualizacin de la situacin de la mejora gentica de girasol para resistencia al jopo June 2014 Helia 33(52):1-12 Planta 235, 11971207. (1999). Elicitation of defense related enzymes and resistance by L-methionine in pearl millet against downy mildew disease caused by Sclerospora graminicola. The economic importance of the phytoparasites Orobanche and Striga, in Proceedings of the Fifth Symposium on Parasitic Weeds, Nairobi, eds J. K. Ransom, L. J. Musselman, A. D. Worsham, and C. Parker (Nairobi: CIMMYT), 137143. Pectin methylesterase in calli and germinating seeds of Orobanche aegyptiaca. Environ. doi: 10.1111/j.1365-3180.2007.00609.x, Fernndez-Aparicio, M., Emeran, A. (2015). resistance available for faba bean breeding. A., and Stewart, G. R. (1978). The Problem of Orobanche spp. Plant Sci. Despite of this fact, Seed Certification Services in some of the countries affected, do not include in their certification standards, inspection of crop seed samples for broomrape inoculum. doi: 10.1007/s13593-013-0153-x, Gibot-Leclerc, S., Corbineau, F., Sall, G., and Cme, D. (2004). 12, 722865. Plant. Figure 1. Although these industry efforts are important, the most effective means to control the spread of this pest is active concern for the presence of this weed in processing tomato fields, Bagley said. 9, 200208. 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). Bandaranayake, P. C. G., and Yoder, J. I. Branched broomrape is so destructive in tomatoes that if it is detected in a growers field, quarantine regulations require that the crop be destroyed and the field be disked under, and common sense dictates that a grower rotate out of host crops for many years, said Brad Hanson, UC Cooperative Extension weed specialist, Department of Plant Sciences, UC Davis. Broomrape attack is more severe on crops growing in low fertility soils. 6, 269275. (2012). 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). doi: 10.1071/SB05009, Thomas, H., Heller, A., Sauerborn, J., and Mller-Stver, D. (1999). The effect of nitrogenous compounds on in vitro germination of Orobanche crenata Forsk. Res. This is how can we live with this without huge yield losses. Res. Fenugreek root exudates show species-specific stimulation of Orobanche seed germination. 101, 261265. Some of the strategies discussed in previous sections such as biological control maintain their control action at post-attachment stages and will not be discussed again in this section. (1991). J. Microbiol. No-tillage improves broomrape control with glyphosate in faba-bean. The role of strigolactones in host specificity of Orobanche and Phelipanche seed germination. Revisiting strategies for reducing the seedbank of Orobanche and Phelipanche spp. Nature 455, 189194. New Phytol. (2015). (1995). 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). (2009). Due to their physical and metabolic overlap with the crop, their underground parasitism, their achlorophyllous nature, and hardly destructible seed bank, broomrape weeds are usually not controlled by management strategies designed for non-parasitic weeds. Dev. Z. Planzenphysiol. Effect of triiodobenzoic acid on broomrape (Orobanche ramosa) infection and development in tomato plants. The flowers are irregularly shaped and produce single-chambered capsules that contain numerous minute seeds. 11, 240246. 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). Dormancy and germination of Orobanche seeds in relation to control methods, in Proceedings of a Workshop in Wageningen: Biology and Control of Orobanche, ed. In non-parasitic plants, physiological dormancy can be relieved through stratification but in the case of broomrape weeds, two consecutive processes are required to release dormancy: an environment-dependent first step of warm stratification called the conditioning phase, and a host-dependent second step of chemodetection. 30, 533591. Germination stimulants of Phelipanche ramosa in the rhizosphere of Brassica napus are derived from the glucosinolate pathway. doi: 10.1016/j.biocontrol.2005.09.017. 12, 638652. 27, 653659. Ann. June 11, 2022 Posted by: what does dep prenotification from us treas 303 mean . Sholmer-Ilan, A. Updates? Study on viability and longevity of Orobanche seed under laboratory conditions, in Proceedings of the International Workshop on Orobanche Research: Progress in Orobanche Research, eds K. Wegmann and L. J. Musselman (Obermarchtal: Eberhard-Karls Universitat), 110114. Though, the effect of L-methionine on internal crop resistance was not studied and requires further investigation. We reviewed relevant facts about the biology and physiology of broomrape weeds and the major feasible control strategies. doi: 10.1111/j.1365-3180.1971.tb01006.x, Stewart, G. R., and Press, M. C. (1990). (2008). in Africa and Near East. 18 Sep 2020. Plakhine, D., Ziadna, H., and Joel, D. M. (2009). 43, 6371. 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 Colonization of field pea roots by arbuscular mycorrhizal fungi reduces Orobanche and Phelipanche species seed germination. Tomilov, A., Tomilova, N., Shin, D. H., Jamison, D., Torres, M., Reagan, R., et al. Benzo-(1,2,3)-thiadiazole-7-carbothioic acid S-methyl ester (BTH) acts as a functional analog of SA and activates defense responses in susceptible hosts leading to lignification of the endodermis and a consequent inhibition to up to 98% broomrape parasitism (Gonsior et al., 2004; Prez-de-Luque et al., 2004; Kusumoto et al., 2007). Bacterial inhibition of Orobanche aegyptiaca and Orobanche cernua radical elongation. Post-germination development in broomrape could be probably regulated by their own broomrape-encoded strigolactones as it occurs in the close related parasite Striga hermonthica or in non-parasitic plants (Liu et al., 2014; Das et al., 2015). Sci. Infection of chickpea (Cicer arietinum) by crenate broomrape (Orobanche crenata) as influenced by sowing date and weather conditions. doi: 10.1017/S001447970100401X. Besides their role as extraorganismal signaling, recent research is uncovering new functions for strigolactones as plant hormone controlling crop development in response to the environment (Gomez-Roldan et al., 2008; Umehara et al., 2008). 47, 452460. doi: 10.2134/agronj2009.0014. Haustorial connection of broomrape with the root of a weed host In south Texas, broomrape seed germination occurs from December to February. eCollection 2022. The moths lay their eggs in the flowers. Sucrose is also metabolized to starch that is accumulated in the broomrape storage organ, the tubercle (Abbes et al., 2009; Draie et al., 2011). doi: 10.1006/anbo.1998.0629, Johnson, A. W., Rosebery, G., and Parker, C. (1976). Ann. They write new content and verify and edit content received from contributors. 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. Symplasmic sieve element continuity between Orobanche and its host. doi: 10.1614/WS-D-11-00113.1. based on a life cycle model. A. C. (1996). doi: 10.1111/j.1469-8137.2006.01787.x. 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). Res. Intercropping with cereals reduces infection by Orobanche crenata in legumes. (2007). FIGURE 2. However, seven broomrape species, Orobanche crenata, O. cernua, O. cumana, O. foetida, O. minor, Phelipanche aegyptiaca, and P. ramosa have specialized on attacking crops causing trouble in agriculture along Mediterranean, central and eastern Europe, and Asia (Parker, 2009). broomrape and bursage relationship. doi: 10.3732/ajb.93.7.1039, Berner, D. K., Schaad, N. W., and Volksch, B. doi: 10.2135/cropsci2004.2221. doi: 10.1111/j.1365-3180.1995.tb01641.x, Gomez-Roldan, V., Fermas, S., Brewer, P. B., Puech-Pages, V., Dun, E. A., Pillot, J. P., et al. It has no root cap and does not develop procambium or conductive tissues (Joel and Losner-Goshen, 1994). doi: 10.1021/jf030025s, Grenz, J. H., Manschadi, A. M., Uygurc, F. N., and Sauerborn, J. Phytoparasitica 32, 2129. doi: 10.1093/pcp/pcr176. Metabolites. 49(Suppl. Biocontrol Sci. inducers of ISR (Gozzo, 2003) and commercially available as Proradix can reduce broomrape parasitism by 80% in susceptible cultivars of hemp and tobacco without phytotoxic effect on the crop (Gonsior et al., 2004). doi: 10.1021/jf5027235, Fernndez-Aparicio, M., Kisugi, T., Xie, X., Rubiales, D., and Yoneyama, K. (2014). 29, 391393. Parasitic plants eavesdrop the plant-to-symbiont communication to sense their hosts and germinate (Xie et al., 2010). doi: 10.1093/molbev/msu343, Yoder, J. I., and Scholes, J. D. (2010). Is seed conditioning essential for Orobanche germination? Seed Sci. 62, 1048510492. doi: 10.1560/ETEL-C34X-Y6MG-YT0M, Veronesi, C., Bonnin, E., Calvez, S., Thalouarn, P., and Simier, P. (2007). Takeuchi, Y., Omigawa, Y., Ogasawara, M., Yoneyama, K., Konnai, M., and Worsham, A. D. (1995). 2018 Aug;102(8):1477-1488. doi: 10.1094/PDIS-01-18-0020-FE. (2009). Bot. For broomrape control, this system seeks the simultaneous cultivation of susceptible host species with inhibitory species of broomrape parasitism. The biology of Striga, Orobanche and other root parasitic weeds. Weed Res. Pseudomonas aeruginosa, P. fluorescens, Bacillus atrophaeus, B. subtilis are promising biocontrol agents targeting the growth of broomrape radicles (Barghouthi and Salman, 2010). Aber, M., Fer, A., and Salle, G. (1983). The presence of strigolactone biosynthetic system in broomrapes raises the question on how the parasite performs diversified stimulant recognition in order to set the timing of germination. 81, 319326. (2009). The major strategy that specifically impedes the broomrape capacity to penetrate the host once the radicle has made contact with host root, is based on the use of host resistance, either genetic resistance obtained by breeding (Prez-de-Luque et al., 2009; Yoder and Scholes, 2010), or induced resistance by abiotic or biotic agents (Gonsior et al., 2004; Kusumoto et al., 2007). Sudan J. Agric. 81, 779781. Phytopathol. 89, 177181. On the contrary, they must be highly susceptible, as the farmer is the one with the role of stopping the parasitic process by harvesting the catch crop as a green vegetable before the parasite emerges. Ecological aspects of nitrogen assimilation. Int. Ehleringer, J. R., and Marshall, J. D. (1995). Food Chem. Low strigolactone root exudation: a novel mechanism of broomrape (Orobanche and Phelipanche spp.) Please also list any non-financial associations or . J. Sources of natural resistance based on reduced release of haustorium-inducing factors is a doubly interesting strategy to inhibit broomrape parasitism because not only it prevents broomrape parasitism in the current crop, but also it promotes the demise of the seed bank by promoting suicidal germination. "It is a prolific seed producer. (2013). Like most seeds, broomrape seeds are resistant to rapid microbial degradation due to phenols located in its testa (Cezard, 1973). Joel, D. M. (2013). 6, 143. doi: 10.1016/j.cropro.2006.10.012, Fernndez-Aparicio, M., Yoneyama, K., and Rubiales, D. (2011). Mayer, A. M., and Bar-Nun, N. (1994). Gain of host sensitivity in broomrape seeds at the end of the conditioning phase is mediated by demethylation of PrCYP707A1 promoter. Joel, D. M. (2000). doi: 10.1016/j.agee.2007.01.014, Gressel, J. In other pathosystems, amino acids such as D-L--amino-n-butyric acid or L-methionine induce resistance in crop plants against pathogen attack. Understanding the key processes of host recognition, haustorium development and maturation and metabolic regulation of the parasitic sink allow virulence predictions and the design and implementation of highly calibrated, feasible, and durable control strategies leading to the arrest of broomrape parasitism minimizing simultaneously environmental impact and yield losses. Biochem. Crop Prot. The structure and development of the haustorium in parasitic Scrophulariaceae. B., and Mallory-Smith, C. A. Evol. (2011). J. Pest Manag. Germinating seeds of the root parasite Orobanche aegyptiaca Pers. In this study, the temperature-dependent relationship was developed into a predictive model based on growing degree-days (GDD) for small broomrape parasitism in red clover. Biomol. Sieve elements of both organisms are already interconnected by interspecific sieve pores at early stages of parasitism. From 1973 to 1982, the California Tomato Research Institute and the industry as a whole spent over $1.5 million on research, surveying and fumigation to achieve eradication levels of this same pest, said Zach Bagley, CTRI managing director. Its not a huge problem, but its not a small one either, and I think its under-reported because it requires crop destruct. Disclaimer. seed germination and radicle growth. (2007a). (2002). News Bull. Nitrate is not toxic to broomrape as it lacks the ability to convert nitrate into ammonium (van Hezewijk and Verkleij, 1996). doi: 10.1111/j.1744-7348.2007.00212.x, Prez-de-Luque, A., and Rubiales, D. (2009). Bot. Crop Prot. doi: 10.1002/ps.567, Aybeke, M., en, B., and kten, S. (2015). A., and Garca-Garrido, J. M. (2009c). Omissions? hellofresh stock concentrate packets. Crops with target-site herbicide resistance for Orobanche and Striga control. doi: 10.1080/09583159929857. PrCYP707A1, an ABA catabolic gene, is a key component of Phelipanche ramosa seed germination in response to the strigolactone analogue GR24. 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. Weed Sci. Several mechanisms underlying this resistance have been described at this stage such as production of gel-like substances within host vessels blocking the transfer of nutrients, host-encoded toxic-compounds delivered into the parasitic tissue though the vascular system and hormonal incompatibility that leads to abnormal haustorial maturation with scarce vascular connections (Fernndez-Aparicio et al., 2008c; Prez-de-Luque et al., 2008, 2009). 65, 553559. doi: 10.1007/s10535-007-0084-y, Vurro, M., Boari, A., Evidente, A., Andolfi, A., and Zermane, N. (2009). (2008). Although some examples of successful control do exist for some crops, the majority of commercially available control methods are either not fully effective or not applicable to many of the affected crops, especially in the case of low-input crops (Joel, 2000). 112 297308. Plant Microbe Interact. Transgenic Res. Ivanovi , Marisavljevi D, Marinkovi R, Mitrovi P, Blagojevi J, Nikoli I, Pavlovi D. Plant Pathol J. This approach is based on the selection of naturally occurring mutants that overproduce and excrete an enhanced amount of specific amino acid with broomrape inhibition properties on seed germination and radicle growth (Vurro et al., 2006; Sands and Pilgeram, 2009). This treatment in the lab mimics the soil conditions in climatically suitable regions for broomrape such as Mediterranean non-irrigated agrosystems where the onset of warm and wet season coincides with the growth of juvenile stages of many annual crops (Lpez-Granados and Garca-Torres, 1996; Grenz and Sauerborn, 2007). Original article from AgAlert, California Farm Bureau Federation.). J. On the contrary, weedy broomrape species are usually generalists attacking annual crops (Schneeweiss, 2007). Control 2 291296. doi: 10.1016/j.plaphy.2005.06.009. 47, 4453. Plant Biol. Although broomrape pre-vascular connections benefits from host nutrients, the growth of broomrape in its way toward vascular cylinder is mainly sustained by consumption of seed reserves (Aber et al., 1983; Joel and Losner-Goshen, 1994; Joel, 2000). Engineered host crops harboring herbicide-resistance transgenes have not yet been commercialized for broomrape management (Gressel, 20092). Although hard seed coat has been described as dormancy mechanism in newly formed broomrape seeds (Lpez-Granados and Garca-Torres, 1996), water uptake and imbibition are performed quickly by mature seeds through the micropyle without the need of scarification (Bar-Nun and Mayer, 1993; Joel et al., 2012). doi: 10.1093/jxb/err246, Fernndez-Aparicio, M., Sillero, J. C., and Rubiales, D. (2007). (2001). Despite the reports of broomrape inefficient machinery for nitrogen assimilation and broomrape dependence for host-derived organic forms of nitrogen demonstrated by the fact that broomrape growth is arrested when feeding on host cultivars with decreased amino acid-phloem levels (Abbes et al., 2009), inhibition of enzymes at the top of amino-acid biosynthetic pathway by means of either direct inhibitory action of herbicides (Gressel, 2009) or by feedback inhibition induced by amino-acid end-products (Vurro et al., 2006) are able to kill broomrape. Sci. Weed Res. Rubiales, D., Alcntara, C., Prez-de-Luque, A., Gil, J., and Sillero, J. C. (2003a). doi: 10.1146/annurev-phyto-073009-114453, Yang, Z., Wafula, E. K., Honaas, L. A., Zhang, H., Das, M., Fernandez-Aparicio, M., et al. Analysis of resistance criteria of sunflower recombined inbred lines against Orobanche cumana Wallr. Appl. Ecosyst. With target-site resistance, the herbicide translocates unmetabolised to the underground broomrape via the haustorium inflicting its suppressive action in the parasite (Gressel, 2009). Effect of fungal and plant metabolites on broomrapes (Orobanche and Phelipanche spp.) 133, 637642. The majority of strategies aimed to manage autotrophic weeds do not necessarily work for broomrapes and those that provide a degree of success for broomrape need to be optimized for each broomrape-crop species combination, local environmental conditions and broomrape population. A simple method for stabilizing and granulating fungi. Mutualism This is a win-win relationship Both organisms . Phytochemistry 34, 3945. doi: 10.1111/j.1438-8677.1995.tb00830.x, Draie, R., Pron, T., Pouvreau, J.-B., Vronsi, C., Jgou, S., Delavault, P., et al. We are trying to hedge our bets, in terms of registering something we can use on tomatoes.. doi: 10.1016/j.pbi.2010.04.011, Yoneyama, K., Xie, X., Kim, H. I., Kisugi, T., Nomura, T., Sekimoto, H., et al. Rev. Abu-Irmaileh B. E. (1994). (2014). Am. Methods for Orobanche and Phelipanche spp. Euphytica 186, 897905. Broomrapes counteract the high risk of failure in establishment on a host with highly evolved mechanisms of survival. Increasing control reliability of Orobanche cumana through integration of a biocontrol agent with a resistance-inducing chemical. In addition long lived seed banks under physiological dormancy ensure that germination will occur when a suitable host in its correct stage of development is present nearby (Rubiales et al., 2009b). doi: 10.1016/0031-9422(95)00594-3, Bar-Nun, N., and Mayer, A. M. (1993). The taxonomy of the group is somewhat contentious, and the American species of broomrape are sometimes placed in the genus Aphyllon. Technologies for smart chemical control of broomrape (Orobanche spp. 49 239248. Crop Prot. "Broomrape is easily spread by equipment, boots and water," he said. 53, 107117. The dynamics of faba bean (Vicia faba L.) parasitism by Orobanche foetida. Crop Prot. J. Agric. The first attempts to deplete parasitic weed seed bank was made by Johnson et al. Phytochemistry 109, 5765. doi: 10.1579/05-R-051R.1. Sci. Non-host facilitators, a new category that unexpectedly favours parasitic weeds. Bot. doi: 10.1093/aob/mcm032, Ben-Hod, G., Losner-Goshen, D., Joel, D. M., and Mayer, A. M. (1993). Ann. not been previously reported. Effect of Brassica campestris var. 10.1016/j.plaphy.2008.10.004 doi: 10.1111/j.1364-3703.2010.00702.x. 70, 183212. Chemical signalling between plants: mechanistic similarities between phytotoxic allelopathy and host recognition by parasitic plants, in Chemical Ecology: From Gene to Ecosystem, eds M. Dicke and W. Takken (Dordrecht: Springer), 5569. Delayed sowing date is a traditional method that can show high degree of success on inhibiting parasitism if implemented correctly (Lpez-Granados and Garca-Torres, 1996; Rubiales et al., 2003a; Prez-de-Luque et al., 2004; Grenz et al., 2005). 42, 464469. They have been traditionally considered the exception in parasitic Orobanchaceae that do not require host factors for haustorium initiation (Joel and Losner-Goshen, 1994; Bandaranayake and Yoder, 2013). Please select which sections you would like to print: Encyclopaedia Britannica's editors oversee subject areas in which they have extensive knowledge, whether from years of experience gained by working on that content or via study for an advanced degree. Epub 2018 Jul 3. Plant sesquiterpenes induce hyphal branching in arbuscular mycorrhizal fungi. Transformation of carrots with mutant acetolactate synthase for Orobanche (broomrape) control. Upon host detection, the broomrape radicle stops elongating and terminal haustorium is differentiated as an anchoring device. Variability of interactions between barrel medic (Medicago truncatula) genotypes and Orobanche species. New Phytol. Proceedings of the International Workshop on Orobanche Research, eds K. Wegmann and L. J. Musselman (Obermarchtal, FRG: Eberhard Karls Universitt), 147156. This strategy requires a careful calibration of doses and timing depending on the host crop and underground phenology of broomrape determined by local conditions and crop (Hershenhorn et al., 1998, 2009; Eizenberg et al., 2006). nature knows best laws of ecology,