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Diego Rubiales - One of the best experts on this subject based on the ideXlab platform.
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induction of haustorium development by sphaeropsidones in radicles of the parasitic weeds striga and Orobanche a structure activity relationship study
Journal of Agricultural and Food Chemistry, 2016Co-Authors: Monica Fernandezaparicio, Diego Rubiales, Marco Masi, Lucia Maddau, Alessio Cimmino, Marco Evidente, Antonio EvidenteAbstract:Crop attack by parasitic weeds such as Striga and Orobanche occurs through developmental processes triggered by host chemodetection. Seeds of those weed species remain dormant in the soil until germination is triggered by host root exudates. The development of haustorium, a parasitic plant organ that invades the host to withdraw its nutrients, is also initiated in Orobanchaceae by host molecular cues. The induction of haustorium development by exogenous signals has previously been reported for Striga but not for Orobanche species. In this work, we demonstrate that sphaeropsidone and epi-sphaeropsidone, two phytotoxic cyclohexene oxides isolated from the fungus Diplodia cupressi, a causal agent of cypress canker, induce haustorium development in radicles of the parasitic weeds Striga hermonthica, Orobanche crenata, and Orobanche cumana. This is the first report of chemical stimulation of haustorium development in radicles of Orobanche in the absence of host. In addition, SAR studies were carried out by tes...
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ryecyanatines a and b and ryecarbonitrilines a and b substituted cyanatophenol cyanatobenzo 1 3 dioxole and benzo 1 3 dioxolecarbonitriles from rye secale cereale l root exudates novel metabolites with allelopathic activity on Orobanche seed germinat
Phytochemistry, 2015Co-Authors: Alessio Cimmino, Koichi Yoneyama, Diego Rubiales, Monica Fernandezaparicio, Fabiana Avolio, Antonio EvidenteAbstract:Abstract Orobanche and Phelipanche species (the broomrapes) are root parasitic plants, some of which represent serious weed problems causing heavy yield losses on important crops. Current control relies on the use of certain agronomic practices, resistant crop varieties, and herbicides, albeit success has been marginal. Agronomic practices such as the use of allelopathic species in intercropping or cover crops, or the use of direct seedling over residues of allelopathic species incorporate the principle of allelopathy exerted by molecules exuded from roots or released by crop residues to control broomrapes. In addition, the isolation of natural substances from root exudates of plants with potential to inhibit broomrape development opens the door to the design of new herbicides based on natural and benign sources. Ryecyanatines A and B and ryecarbonitrilines A and B, the first new substituted cyanatophenol, substituted cyanatobenzo[1,3]dioxole, and the latter two new substituted benzo[1,3]dioxolecarbonitriles were isolated from rye ( Secale cereale L.) root exudates. They were characterized as 4-cyanato-2-methoxyphenol, 2-cyanato-benzo[1,3]dioxole, 2-methoxybenzo[1,3]dioxole-5-carbonitrile and benzo[1,3]dioxole-2-carbonitrile by spectroscopic (essentially NMR and HRESI MS spectra) methods. These compounds were investigated for allelopathic activity on Orobanche germination and development. Ryecarbonitriline A induced germination of Orobanche cumana seeds, and this germination can be considered as suicidal because O. cumana does not parasite rye roots and cannot survive without host resources beyond germination stage. In addition, ryecyanatine A promotes a rapid cessation of O. cumana , Orobanche crenata and Orobanche minor radicle growth with the promotion of a layer of papillae at the radicle tip in O. cumana and O. crenata hampering the contact of the parasite to the host. Ryecarbonitriline B also displayed the same activity although being less active than ryecyanatine A and mainly restricted to O. cumana .
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revisiting strategies for reducing the seedbank of Orobanche and phelipanche spp
Weed Research, 2009Co-Authors: Diego Rubiales, K. Wegmann, Monica Fernandezaparicio, D M JoelAbstract:Summary Weedy Orobanche and Phelipanche species are important in Southern and Eastern Europe, the Middle East and North Africa, and have recently been reported in the USA, Australia and some countries in South America. Rather than being controlled, the Orobanche and Phelipanche problem is increasing, both in intensity and in acreage. Large areas of new territory are at risk of invasion, if care is not immediately taken to limit the introduction of parasitic seeds and to educate farmers and others to be alert for new infestations. There is an urgent need to re-evaluate novel integrated Orobanche and Phelipanche management programmes that will allow a better control of the parasite species and limit their distribution. The main obstacle in the long-term management of Orobanche and Phelipanche infested fields is the durable seedbank, which may remain viable for decades in the field. Large quantities of long-lived seeds give the parasite genetic adaptability to changes in host resistance and cultural practices. As long as the seedbank is not controlled, the need to control the parasite will persist whenever a susceptible host is grown in the infested field. We discuss strategies for seedbank reduction, paying particular attention to cultural practices, whereas chemical and biological control methods are covered by other reviews in this issue.
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Resistance to broomrape species (Orobanche spp.) in common vetch (Vicia sativa L.)
Crop Protection, 2008Co-Authors: Mónica Fernández-aparicio, Josefina C. Sillero, Diego RubialesAbstract:Abstract Common vetch ( Vicia sativa ) is widely used as green manure, pasture, silage, hay and for grain for livestock feed. Its major areas of cultivation coincide with areas of heavy infestation by broomrapes, mainly Orobanche crenata , but also Orobanche aegyptiaca and Orobanche foetida . We report resistance against O. crenata in V. sativa observed in the field, and characterised for selected resistant accessions both in pots and mini-rhizotrons against several Orobanche species. All species studied formed tubercles on common vetch although in varying densities depending on the species and the accessions. However a significant proportion of these became necrotic and died, with frequencies varying with Orobanche species and V. sativa accessions. The cultivar Mezquita is more resistant than PI-183723 against the two populations of O. crenata studied, and also against O. aegyptiaca . However the mechanistic basis of the resistance of Mezquita seems to differ with the Orobanche species. Its resistance against O. crenata is based on retarded development of established tubercles, whereas resistance against O. aegyptiaca is active earlier reducing tubercle formation.
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Variability of interactions between barrel medic (Medicago truncatula) genotypes and Orobanche species
Annals of Applied Biology, 2008Co-Authors: Mónica Fernández-aparicio, Alejandro Pérez-de-luque, Elena Prats, Diego RubialesAbstract:A number of broomrapes (Orobanche spp.) are major threats for grain legumes in the Mediterranean area. Previous studies have shown very high levels of resistance to Orobanche crenata in Medicago truncatula with little variation among accessions hampering, therefore, its use for genetic analysis. In order to identify alternative systems for ulterior genetic and genomic analysis, we studied early stages of the interaction between M. truncatula accessions and a range of Orobanche species. We found significant differences in the induction of germination on Orobanche aegyptiaca, Orobanche foetida var. broteri, Orobanche minor, Orobanche nana and Orobanche ramosa seeds. Accessions also varied in the number of O. aegyptiaca, O. crenata, O. foetida var. broteri, O. nana and 0. ramosa attachments supported. Applications of the synthetic germination stimulant GR24 increased the germination level of Orobanche cumana and 0. minor. No attachments were observed for any of these species because of physical barriers typical of host resistance. On the contrary, increase of 0. nana germination by GR24 led to an increase in number of attachments albeit the normal development of the nodules was stopped in a later stage. The genetic variation observed for induction of germination and subsequent attachment will be useful for isolating and characterising genes involved in early stages of Orobanche-host plant interaction and for the study of the biosynthetic pathways of production of germination stimulants.
Antonio Evidente - One of the best experts on this subject based on the ideXlab platform.
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induction of haustorium development by sphaeropsidones in radicles of the parasitic weeds striga and Orobanche a structure activity relationship study
Journal of Agricultural and Food Chemistry, 2016Co-Authors: Monica Fernandezaparicio, Diego Rubiales, Marco Masi, Lucia Maddau, Alessio Cimmino, Marco Evidente, Antonio EvidenteAbstract:Crop attack by parasitic weeds such as Striga and Orobanche occurs through developmental processes triggered by host chemodetection. Seeds of those weed species remain dormant in the soil until germination is triggered by host root exudates. The development of haustorium, a parasitic plant organ that invades the host to withdraw its nutrients, is also initiated in Orobanchaceae by host molecular cues. The induction of haustorium development by exogenous signals has previously been reported for Striga but not for Orobanche species. In this work, we demonstrate that sphaeropsidone and epi-sphaeropsidone, two phytotoxic cyclohexene oxides isolated from the fungus Diplodia cupressi, a causal agent of cypress canker, induce haustorium development in radicles of the parasitic weeds Striga hermonthica, Orobanche crenata, and Orobanche cumana. This is the first report of chemical stimulation of haustorium development in radicles of Orobanche in the absence of host. In addition, SAR studies were carried out by tes...
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ryecyanatines a and b and ryecarbonitrilines a and b substituted cyanatophenol cyanatobenzo 1 3 dioxole and benzo 1 3 dioxolecarbonitriles from rye secale cereale l root exudates novel metabolites with allelopathic activity on Orobanche seed germinat
Phytochemistry, 2015Co-Authors: Alessio Cimmino, Koichi Yoneyama, Diego Rubiales, Monica Fernandezaparicio, Fabiana Avolio, Antonio EvidenteAbstract:Abstract Orobanche and Phelipanche species (the broomrapes) are root parasitic plants, some of which represent serious weed problems causing heavy yield losses on important crops. Current control relies on the use of certain agronomic practices, resistant crop varieties, and herbicides, albeit success has been marginal. Agronomic practices such as the use of allelopathic species in intercropping or cover crops, or the use of direct seedling over residues of allelopathic species incorporate the principle of allelopathy exerted by molecules exuded from roots or released by crop residues to control broomrapes. In addition, the isolation of natural substances from root exudates of plants with potential to inhibit broomrape development opens the door to the design of new herbicides based on natural and benign sources. Ryecyanatines A and B and ryecarbonitrilines A and B, the first new substituted cyanatophenol, substituted cyanatobenzo[1,3]dioxole, and the latter two new substituted benzo[1,3]dioxolecarbonitriles were isolated from rye ( Secale cereale L.) root exudates. They were characterized as 4-cyanato-2-methoxyphenol, 2-cyanato-benzo[1,3]dioxole, 2-methoxybenzo[1,3]dioxole-5-carbonitrile and benzo[1,3]dioxole-2-carbonitrile by spectroscopic (essentially NMR and HRESI MS spectra) methods. These compounds were investigated for allelopathic activity on Orobanche germination and development. Ryecarbonitriline A induced germination of Orobanche cumana seeds, and this germination can be considered as suicidal because O. cumana does not parasite rye roots and cannot survive without host resources beyond germination stage. In addition, ryecyanatine A promotes a rapid cessation of O. cumana , Orobanche crenata and Orobanche minor radicle growth with the promotion of a layer of papillae at the radicle tip in O. cumana and O. crenata hampering the contact of the parasite to the host. Ryecarbonitriline B also displayed the same activity although being less active than ryecyanatine A and mainly restricted to O. cumana .
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fenugreek root exudates show species specific stimulation of Orobanche seed germination
Weed Research, 2008Co-Authors: Monica Fernandezaparicio, Anna Andolfi, Antonio Evidente, Alejandro Perezdeluque, Diego RubialesAbstract:Summary Various Orobanche species are weedy and cause severe reduction in the yields of many important crops. The seeds of these parasitic weeds may remain dormant in the soil for many years until germination is stimulated by the release of a chemical signal from a host plant. In order to determine the effects of fenugreek root exudate on the induction of Orobanche crenata, Orobanche ramosa and Orobanche foetida seed germination, root exudate was collected from hydroponically grown fenugreek seedlings. Fractionation patterns obtained from column and thin layer chromatography of the fenugreek root exudate showed a set of metabolites differing in their polarity with stimulatory activity on Orobanche seed germination. The crude root exudate stimulated both O. ramosa and O. crenata seed germination to the same level caused by the synthetic germination stimulant GR24 at 10 mg L−1. It also stimulated O. foetida seed germination which did not respond to GR24. Active fractions of root exudate stimulated the germination of Orobanche species differentially.
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metabolites inhibiting germination of Orobanche ramosa seeds produced by myrothecium verrucaria and fusarium compactum
Journal of Agricultural and Food Chemistry, 2005Co-Authors: Anna Andolfi, Angela Boari, Antonio Evidente, Maurizio VurroAbstract:Myrothecium verrucaria and Fusarium compactum were isolated from diseased Orobanche ramosa plants collected in southern Italy to find potential biocontrol agents of this parasitic weed. Both fungi grown in liquid culture produced metabolites that inhibited the germination of O. ramosa seeds at 1−10 μM. Eight metabolites were isolated from M. verrucaria culture extracts. The main metabolite was identified as verrucarin E, a disubstituted pyrrole not belonging to the trichothecene group. Seven compounds were identified by spectroscopic methods as macrocyclic trichothecenes, namely, verrucarins A, B, M, and L acetate, roridin A, isotrichoverrin B, and trichoverrol B. The main metabolite produced by F. compactum was neosoloaniol monoacetate, a trichothecene. All the trichothecenes proved to be potent inhibitors of O. ramosa seed germination and possess strong zootoxic activity when assayed on Artemia salina brine shrimps. Verrucarin E is inactive on both seed germination and zootoxic assay. Keywords: Orobanch...
Daniel M Joel - One of the best experts on this subject based on the ideXlab platform.
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dehydrocostus lactone is exuded from sunflower roots and stimulates germination of the root parasite Orobanche cumana
Phytochemistry, 2011Co-Authors: Daniel M Joel, Dina Plakhine, Swapan K Chaudhuri, Hammam Ziadna, John C SteffensAbstract:The germination of the obligate root parasites of the Orobanchaceae depends on the perception of chemical stimuli from host roots. Several compounds, collectively termed strigolactones, stimulate the germination of the various Orobanche species, but do not significantly elicit germination of Orobanche cumana, a specific parasite of sunflower. Phosphate starvation markedly decreased the stimulatory activity of sunflower root exudates toward O. cumana, and fluridone - an inhibitor of the carotenoid biosynthesis pathway - did not inhibit the production of the germination stimulant in both shoots and roots of young sunflower plants, indicating that the stimulant is not a strigolactone. We identified the natural germination stimulant from sunflower root exudates by bioassay-driven purification. Its chemical structure was elucidated as the guaianolide sesquiterpene lactone dehydrocostus lactone (DCL). Low DCL concentrations effectively stimulate the germination of O. cumana seeds but not of Phelipanche aegyptiaca (syn. Orobanche aegyptiaca). DCL and other sesquiterpene lactones were found in various plant organs, but were previously not known to be exuded to the rhizosphere where they can interact with other organisms.
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gene silencing of mannose 6 phosphate reductase in the parasitic weed Orobanche aegyptiaca through the production of homologous dsrna sequences in the host plant
Plant Biotechnology Journal, 2009Co-Authors: Hila Cholakh, Daniel M Joel, Diana Leibman, Benjamin Steinitz, Aaron Zelcer, Anna Naglis, Oded Yarden, Amit GalonAbstract:Abstract Orobanche spp. (broomrape) are parasitic plants which subsist on the roots of a wide range of hosts, including tomato, causing severe losses in yield quality and quantity. Large amounts of mannitol accumulate in this parasitic weed during development. Mannose 6-phosphate reductase (M6PR) is a key enzyme in mannitol biosynthesis, and it has been suggested that mannitol accumulation may be very important for Orobanche development. Therefore, the Orobanche M6PR gene is a potential target for efforts to control this parasite. Transgenic tomato plants were produced bearing a gene construct containing a specific 277-bp fragment from Orobanche aegyptiaca M6PR-mRNA, in an inverted-repeat configuration. M6PR-siRNA was detected in three independent transgenic tomato lines in the R1 generation, but was not detected in the parasite. Quantitative RT-PCR analysis showed that the amount of endogenous M6PR mRNA in the tubercles and underground shoots of O. aegyptiaca grown on transgenic host plants was reduced by 60%-80%. Concomitant with M6PR mRNA suppression, there was a significant decrease in mannitol level and a significant increase in the percentage of dead O. aegyptiaca tubercles on the transgenic host plants. The detection of mir390, which is involved with cytoplasmic dsRNA processing, is the first indication of the existence of gene-silencing mechanisms in Orobanche spp. Gene silencing mechanisms are probably involved with the production of decreased levels of M6PR mRNA in the parasites grown on the transformed tomato lines.
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germination response of Orobanche seeds subjected to conditioning temperature water potential and growth regulator treatments
Weed Research, 2005Co-Authors: W J Song, Weijun Zhou, Daniel M Joel, Yasutomo Takeuchi, Koichi YoneyamaAbstract:Broomrapes (Orohanche spp.) are parasitic weeds that cause significant losses of crop yield. Experiments were conducted to investigate the seed response to the artificial germination stimulant GR 24 in three species of Orobanche subjected to preconditioning under various temperatures, water potentials and with plant growth regulators. The highest germination percentages were observed in Orobanche ramosa, Orohanche aegyptiaca and Orohanche minor seeds conditioned at 18°C for 7 days followed by germination stimulation at 18°C. With the increase of the conditioning period (7, 14, 21 and 28 days), the germination percentage of O. ramosa and O. aegyptiaca progressively decreased. When conditioned at -2 MPa, the germination percentage was lower than at 0 and -1 MPa, especially at 13 and 28°C. Orohanche minor seeds could retain relatively high germination if conditioned at 18, 23 or 28°C, even after significantly extended conditioning periods (up to 84 days). GA 3 (30-100 mg L -1 ), norflurazon and fluridone (10-100 mg L -1 ), and brassinolide (0.5-1.0 mg L -1 ) increased seed germination, while 0.01 mg L -1 uniconazole significantly reduced germination rates of all three Orobanche spp. The promotional effects of GA 3 and norflurazon and the inhibitory effect of uniconazole were evident, even when they were treated for 3 days. Germination of Orobanche seeds was much lower when the unconditioned seeds were directly exposed to GR 24 at 10 -6 M. This early GR 24 -induced inhibition was however alleviated or even eliminated by the inclusion of GA 3 or norflurazon (10-50 mg L -1 ) in the conditioning medium. On the contrary, the inclusion of uniconazole increased the inhibitory effect of GR 24 , particularly in the case of O. ramosa.
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in vitro infection of host roots by differentiated calli of the parasitic plant Orobanche
Journal of Experimental Botany, 2004Co-Authors: Weijun Zhou, Yasutomo Takeuchi, Koichi Yoneyama, S Rungmekarat, Sang Heon Chae, Daisuke Sato, Daniel M JoelAbstract:Root parasites of the genus Orobanche are serious weeds in agriculture. An aseptic infection system of host roots using calli of three Orobanche species was developed for the study of host‐parasite interaction. The response of calli to various hormonal combinations was studied, because a requirement for infection is the differentiation of root-like protrusions, which are capable of producing haustorial connections to the host. Infectious root-like protrusions develop under the influence of 0.5‐1.0 mg l ‐1 IAA, and under the combination of 0.2 mg l ‐1 NAA with 5.0 mg l ‐1 kinetin. These protocols produced root protrusions with pad-like structures that resembled attachment organs of Orobanche seedlings, and proved effective in parasitizing host roots. Direct contact with the medium inhibited haustorium development and prevented infection. To overcome this problem, certain root portions were isolated from the medium by inserting thin glass plates underneath. Calli were then placed on the raised root portions and successfully infected the roots and developed young Orobanche tubercles with vascular system that directly connected to the host.
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In Vitro Culture of Orobanche aegyptiaca
Annals of Botany, 1991Co-Authors: Dalia Losner, Daniel M Joel, Alfred M. MayerAbstract:Calli derived from seedlings of the parasitic plant Orobanche aegyptiaca were grown on enriched nutrient agar. Growth was enhanced by the addition of 0.1 mg l -1 NAA and 5% coconut milk. The calli developed two kinds of elongated protrusions: thin ones which resemble the young root radicle and thick ones which resemble the adventitious roots of Orobanche plants. Both formed pad-like structures when touching the substrate. In liquid culture, some of the calli were observed to surround isolated cultured tomato roots
Koichi Yoneyama - One of the best experts on this subject based on the ideXlab platform.
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ryecyanatines a and b and ryecarbonitrilines a and b substituted cyanatophenol cyanatobenzo 1 3 dioxole and benzo 1 3 dioxolecarbonitriles from rye secale cereale l root exudates novel metabolites with allelopathic activity on Orobanche seed germinat
Phytochemistry, 2015Co-Authors: Alessio Cimmino, Koichi Yoneyama, Diego Rubiales, Monica Fernandezaparicio, Fabiana Avolio, Antonio EvidenteAbstract:Abstract Orobanche and Phelipanche species (the broomrapes) are root parasitic plants, some of which represent serious weed problems causing heavy yield losses on important crops. Current control relies on the use of certain agronomic practices, resistant crop varieties, and herbicides, albeit success has been marginal. Agronomic practices such as the use of allelopathic species in intercropping or cover crops, or the use of direct seedling over residues of allelopathic species incorporate the principle of allelopathy exerted by molecules exuded from roots or released by crop residues to control broomrapes. In addition, the isolation of natural substances from root exudates of plants with potential to inhibit broomrape development opens the door to the design of new herbicides based on natural and benign sources. Ryecyanatines A and B and ryecarbonitrilines A and B, the first new substituted cyanatophenol, substituted cyanatobenzo[1,3]dioxole, and the latter two new substituted benzo[1,3]dioxolecarbonitriles were isolated from rye ( Secale cereale L.) root exudates. They were characterized as 4-cyanato-2-methoxyphenol, 2-cyanato-benzo[1,3]dioxole, 2-methoxybenzo[1,3]dioxole-5-carbonitrile and benzo[1,3]dioxole-2-carbonitrile by spectroscopic (essentially NMR and HRESI MS spectra) methods. These compounds were investigated for allelopathic activity on Orobanche germination and development. Ryecarbonitriline A induced germination of Orobanche cumana seeds, and this germination can be considered as suicidal because O. cumana does not parasite rye roots and cannot survive without host resources beyond germination stage. In addition, ryecyanatine A promotes a rapid cessation of O. cumana , Orobanche crenata and Orobanche minor radicle growth with the promotion of a layer of papillae at the radicle tip in O. cumana and O. crenata hampering the contact of the parasite to the host. Ryecarbonitriline B also displayed the same activity although being less active than ryecyanatine A and mainly restricted to O. cumana .
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sorgomol germination stimulant for root parasitic plants produced by sorghum bicolor
Tetrahedron Letters, 2008Co-Authors: Kaori Yoneyama, Yasutomo Takeuchi, Dai Kusumoto, Yoichi Yamada, Yukihiro Sugimoto, Koichi YoneyamaAbstract:A novel strigolactone sorgomol, germination stimulant for root parasitic plants Striga and Orobanche, was isolated and structure was elucidated. Sorgomol was more active on Striga than on Orobanche and may be the immediate precursor of sorgolactone in the biosynthetic pathway of strigolactones.
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germination response of Orobanche seeds subjected to conditioning temperature water potential and growth regulator treatments
Weed Research, 2005Co-Authors: W J Song, Weijun Zhou, Daniel M Joel, Yasutomo Takeuchi, Koichi YoneyamaAbstract:Broomrapes (Orohanche spp.) are parasitic weeds that cause significant losses of crop yield. Experiments were conducted to investigate the seed response to the artificial germination stimulant GR 24 in three species of Orobanche subjected to preconditioning under various temperatures, water potentials and with plant growth regulators. The highest germination percentages were observed in Orobanche ramosa, Orohanche aegyptiaca and Orohanche minor seeds conditioned at 18°C for 7 days followed by germination stimulation at 18°C. With the increase of the conditioning period (7, 14, 21 and 28 days), the germination percentage of O. ramosa and O. aegyptiaca progressively decreased. When conditioned at -2 MPa, the germination percentage was lower than at 0 and -1 MPa, especially at 13 and 28°C. Orohanche minor seeds could retain relatively high germination if conditioned at 18, 23 or 28°C, even after significantly extended conditioning periods (up to 84 days). GA 3 (30-100 mg L -1 ), norflurazon and fluridone (10-100 mg L -1 ), and brassinolide (0.5-1.0 mg L -1 ) increased seed germination, while 0.01 mg L -1 uniconazole significantly reduced germination rates of all three Orobanche spp. The promotional effects of GA 3 and norflurazon and the inhibitory effect of uniconazole were evident, even when they were treated for 3 days. Germination of Orobanche seeds was much lower when the unconditioned seeds were directly exposed to GR 24 at 10 -6 M. This early GR 24 -induced inhibition was however alleviated or even eliminated by the inclusion of GA 3 or norflurazon (10-50 mg L -1 ) in the conditioning medium. On the contrary, the inclusion of uniconazole increased the inhibitory effect of GR 24 , particularly in the case of O. ramosa.
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in vitro infection of host roots by differentiated calli of the parasitic plant Orobanche
Journal of Experimental Botany, 2004Co-Authors: Weijun Zhou, Yasutomo Takeuchi, Koichi Yoneyama, S Rungmekarat, Sang Heon Chae, Daisuke Sato, Daniel M JoelAbstract:Root parasites of the genus Orobanche are serious weeds in agriculture. An aseptic infection system of host roots using calli of three Orobanche species was developed for the study of host‐parasite interaction. The response of calli to various hormonal combinations was studied, because a requirement for infection is the differentiation of root-like protrusions, which are capable of producing haustorial connections to the host. Infectious root-like protrusions develop under the influence of 0.5‐1.0 mg l ‐1 IAA, and under the combination of 0.2 mg l ‐1 NAA with 5.0 mg l ‐1 kinetin. These protocols produced root protrusions with pad-like structures that resembled attachment organs of Orobanche seedlings, and proved effective in parasitizing host roots. Direct contact with the medium inhibited haustorium development and prevented infection. To overcome this problem, certain root portions were isolated from the medium by inserting thin glass plates underneath. Calli were then placed on the raised root portions and successfully infected the roots and developed young Orobanche tubercles with vascular system that directly connected to the host.
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alectrol and orobanchol germination stimulants for Orobanche minor from its host red clover
Phytochemistry, 1998Co-Authors: Takao Yokota, Koichi Yoneyama, Hidenori Sakai, Keiji Okuno, Yasutomo TakeuchiAbstract:Abstract Three seed germination stimulants for a parasitic weed, clover broomrape ( Orobanche minor ), were isolated from the root exudate of its host, red clover ( Trifolium pratense ) and structures of the two of the stimulants were determined. One was identified as alectrol and the other was a novel strigol-related compound which was named orobanchol. Orobanchol was tentatively proposed to be a strigol isomer based on its MS and NMR spectral data. This is the first report on germination stimulants of Orobanche spp. from genuine host plants. GC-MS techniques to analyze strigolactones are also described.
Monica Fernandezaparicio - One of the best experts on this subject based on the ideXlab platform.
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induction of haustorium development by sphaeropsidones in radicles of the parasitic weeds striga and Orobanche a structure activity relationship study
Journal of Agricultural and Food Chemistry, 2016Co-Authors: Monica Fernandezaparicio, Diego Rubiales, Marco Masi, Lucia Maddau, Alessio Cimmino, Marco Evidente, Antonio EvidenteAbstract:Crop attack by parasitic weeds such as Striga and Orobanche occurs through developmental processes triggered by host chemodetection. Seeds of those weed species remain dormant in the soil until germination is triggered by host root exudates. The development of haustorium, a parasitic plant organ that invades the host to withdraw its nutrients, is also initiated in Orobanchaceae by host molecular cues. The induction of haustorium development by exogenous signals has previously been reported for Striga but not for Orobanche species. In this work, we demonstrate that sphaeropsidone and epi-sphaeropsidone, two phytotoxic cyclohexene oxides isolated from the fungus Diplodia cupressi, a causal agent of cypress canker, induce haustorium development in radicles of the parasitic weeds Striga hermonthica, Orobanche crenata, and Orobanche cumana. This is the first report of chemical stimulation of haustorium development in radicles of Orobanche in the absence of host. In addition, SAR studies were carried out by tes...
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ryecyanatines a and b and ryecarbonitrilines a and b substituted cyanatophenol cyanatobenzo 1 3 dioxole and benzo 1 3 dioxolecarbonitriles from rye secale cereale l root exudates novel metabolites with allelopathic activity on Orobanche seed germinat
Phytochemistry, 2015Co-Authors: Alessio Cimmino, Koichi Yoneyama, Diego Rubiales, Monica Fernandezaparicio, Fabiana Avolio, Antonio EvidenteAbstract:Abstract Orobanche and Phelipanche species (the broomrapes) are root parasitic plants, some of which represent serious weed problems causing heavy yield losses on important crops. Current control relies on the use of certain agronomic practices, resistant crop varieties, and herbicides, albeit success has been marginal. Agronomic practices such as the use of allelopathic species in intercropping or cover crops, or the use of direct seedling over residues of allelopathic species incorporate the principle of allelopathy exerted by molecules exuded from roots or released by crop residues to control broomrapes. In addition, the isolation of natural substances from root exudates of plants with potential to inhibit broomrape development opens the door to the design of new herbicides based on natural and benign sources. Ryecyanatines A and B and ryecarbonitrilines A and B, the first new substituted cyanatophenol, substituted cyanatobenzo[1,3]dioxole, and the latter two new substituted benzo[1,3]dioxolecarbonitriles were isolated from rye ( Secale cereale L.) root exudates. They were characterized as 4-cyanato-2-methoxyphenol, 2-cyanato-benzo[1,3]dioxole, 2-methoxybenzo[1,3]dioxole-5-carbonitrile and benzo[1,3]dioxole-2-carbonitrile by spectroscopic (essentially NMR and HRESI MS spectra) methods. These compounds were investigated for allelopathic activity on Orobanche germination and development. Ryecarbonitriline A induced germination of Orobanche cumana seeds, and this germination can be considered as suicidal because O. cumana does not parasite rye roots and cannot survive without host resources beyond germination stage. In addition, ryecyanatine A promotes a rapid cessation of O. cumana , Orobanche crenata and Orobanche minor radicle growth with the promotion of a layer of papillae at the radicle tip in O. cumana and O. crenata hampering the contact of the parasite to the host. Ryecarbonitriline B also displayed the same activity although being less active than ryecyanatine A and mainly restricted to O. cumana .
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revisiting strategies for reducing the seedbank of Orobanche and phelipanche spp
Weed Research, 2009Co-Authors: Diego Rubiales, K. Wegmann, Monica Fernandezaparicio, D M JoelAbstract:Summary Weedy Orobanche and Phelipanche species are important in Southern and Eastern Europe, the Middle East and North Africa, and have recently been reported in the USA, Australia and some countries in South America. Rather than being controlled, the Orobanche and Phelipanche problem is increasing, both in intensity and in acreage. Large areas of new territory are at risk of invasion, if care is not immediately taken to limit the introduction of parasitic seeds and to educate farmers and others to be alert for new infestations. There is an urgent need to re-evaluate novel integrated Orobanche and Phelipanche management programmes that will allow a better control of the parasite species and limit their distribution. The main obstacle in the long-term management of Orobanche and Phelipanche infested fields is the durable seedbank, which may remain viable for decades in the field. Large quantities of long-lived seeds give the parasite genetic adaptability to changes in host resistance and cultural practices. As long as the seedbank is not controlled, the need to control the parasite will persist whenever a susceptible host is grown in the infested field. We discuss strategies for seedbank reduction, paying particular attention to cultural practices, whereas chemical and biological control methods are covered by other reviews in this issue.
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fenugreek root exudates show species specific stimulation of Orobanche seed germination
Weed Research, 2008Co-Authors: Monica Fernandezaparicio, Anna Andolfi, Antonio Evidente, Alejandro Perezdeluque, Diego RubialesAbstract:Summary Various Orobanche species are weedy and cause severe reduction in the yields of many important crops. The seeds of these parasitic weeds may remain dormant in the soil for many years until germination is stimulated by the release of a chemical signal from a host plant. In order to determine the effects of fenugreek root exudate on the induction of Orobanche crenata, Orobanche ramosa and Orobanche foetida seed germination, root exudate was collected from hydroponically grown fenugreek seedlings. Fractionation patterns obtained from column and thin layer chromatography of the fenugreek root exudate showed a set of metabolites differing in their polarity with stimulatory activity on Orobanche seed germination. The crude root exudate stimulated both O. ramosa and O. crenata seed germination to the same level caused by the synthetic germination stimulant GR24 at 10 mg L−1. It also stimulated O. foetida seed germination which did not respond to GR24. Active fractions of root exudate stimulated the germination of Orobanche species differentially.