Parasitic Weeds: Biology and Control

A special issue of Plants (ISSN 2223-7747). This special issue belongs to the section "Plant Protection and Biotic Interactions".

Deadline for manuscript submissions: closed (31 December 2021) | Viewed by 27918

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Special Issue Editors


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Guest Editor
Department of Weed Research, Agricultural Research Organization (ARO), Newe Ya'ar Research Center, Ramat Yishay 30095, Israel
Interests: weed science; parasitic plants; biological control; strigolactones; herbicides resistance

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Guest Editor
The Robert H. Smith Institute of Plant Sciences & Genetics in Agriculture, Faculty of Agriculture, Food & Environment, The Hebrew University of Jerusalem, Rehovot 76100, Israel
Interests: parasitic plants; invasive plants; weeds; weed control; cover crops; crops

Special Issue Information

Dear Colleagues,

Plant parasitism is a case of extreme plant-to-plant interaction whereby parasitic plants connect directly to the vasculature system of a host plant, drawing from its water, nutrients, and assimilates. During their evolution from non-parasitic origins, parasitic plants have developed many specific functions, such as host detection, host attachment, host exploitation, and host defense suppression. The world of parasitic plants includes about 20 families with a wide trophic spectrum, from facultative hemiparasites, which are able to perform photosynthesis and therefore may survive without a connection to the host, to obligatory holoparasites, which have no photosynthetic abilities. Some parasitic species are noxious weeds and damage major agricultural crops, causing heavy economical losses worldwide.

The parasitic lifestyle in plants has always been the subject of the curiosity of scientists, but during the last decade, our understanding of the parasitic plant–host interaction has greatly evolved due to rapid advances in molecular and genomic tools, such as high-throughput DNA sequencing, transcriptomics, and metabolomics. The latest findings take the science of parasitic plants to a higher level, and open up new horizons in parasitic plant management. The discovery of a novel family of phytohormones, the strigolactones, and their involvement in host detection and the evolution of parasitic plants, the discovery of the information exchange between host and parasite, and the elucidation of the parasite’s suppression of the host’s defense mechanism have led to a deeper understanding of physiological processes in host–parasite interaction. In the light of recent achievements, the re-evaluation of control management, including crop breeding and molecular genetics, is on the agenda.

This Special Issue will be focused on both research articles and reviews providing new insights into the field of parasitic plants, including topics such as parasitic plants’ biology and life cycle, the physiology of parasitism, genetics, evolution, population dynamics, host–parasite interaction, etc. Valuable articles dealing with new strategies in parasitic plant management are very welcome.

Call for student papers:

We strongly invite M.Sc. and Ph.D. students to submit papers resulting from their thesis and research, within the topic of ‘Parasitic plants- biology and control’. The outstanding student paper picked by the editors will be granted a waiver on the publication fee. Please see the instruction for authors at https://www.mdpi.com/journal/plants/instructions.

Dr. Evgenia Dor
Dr. Yaakov Goldwasser
Guest Editors

Manuscript Submission Information

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Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Plants is an international peer-reviewed open access semimonthly journal published by MDPI.

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Keywords

  • biological control
  • host range
  • parasitic plants
  • parasitic plants genome
  • weed management
  • plant–host interaction
  • plant resistance
  • strigolactones

Published Papers (12 papers)

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Editorial

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2 pages, 200 KiB  
Editorial
“Parasitic Weeds: Biology and Control” Special Issue Editors Summary
by Evgenia Dor and Yaakov Goldwasser
Plants 2022, 11(14), 1891; https://doi.org/10.3390/plants11141891 - 21 Jul 2022
Cited by 1 | Viewed by 1012
Abstract
We are happy to summarize this important Special Issue (SI) of MDPI Plants—“Parasitic Weeds: Biology and Control” [...] Full article
(This article belongs to the Special Issue Parasitic Weeds: Biology and Control)

Research

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10 pages, 1493 KiB  
Article
Good News for Cabbageheads: Controlling Phelipanche aegyptiaca Infestation under Hydroponic and Field Conditions
by Amit Wallach, Guy Achdari and Hanan Eizenberg
Plants 2022, 11(9), 1107; https://doi.org/10.3390/plants11091107 - 19 Apr 2022
Cited by 4 | Viewed by 1524
Abstract
Phelipanche aegyptiaca (Orobanchaceae) is a parasitic weed that causes severe yield losses in field crops around the world. After establishing vascular connections to the host plant roots, P. aegyptiaca becomes a major sink that draws nutrients, minerals, and water from the host, resulting [...] Read more.
Phelipanche aegyptiaca (Orobanchaceae) is a parasitic weed that causes severe yield losses in field crops around the world. After establishing vascular connections to the host plant roots, P. aegyptiaca becomes a major sink that draws nutrients, minerals, and water from the host, resulting in extensive crop damage. One of the most effective ways to manage P. aegyptiaca infestations is through the use of herbicides. Our main objective was to optimize the dose and application protocol of herbicides that effectively control P. aegyptiaca but do not damage the cabbage crop. The interactions between the cabbage roots and the parasite were first examined in a hydroponic system to investigate the effect of herbicides on initial parasitism stages, e.g., germination, attachment, and tubercles production. Thereafter, the efficacy of glyphosate and ethametsulfuron-methyl in controlling P. aegyptiaca was examined in five cabbage fields naturally infested with P. aegyptiaca. The herbicides glyphosate and ethametsulfuron-methyl were applied on cabbage foliage and in the soil solution, both before and after the parasite had attached to the host roots. A hormesis effect was observed when glyphosate was applied at a dose of 36 g ae ha−1 in a non-infested P. aegyptiaca field. Three sequential herbicide applications (21, 35, and 49 days after planting) effectively controlled P. aegyptiaca without damaging the cabbages at a dose of 72 g ae ha−1 for glyphosate and at all the examined doses for ethametsulfuron-methyl. Parasite control with ethametsulfuron-methyl was also effective when overhead irrigation was applied after the herbicide application. Full article
(This article belongs to the Special Issue Parasitic Weeds: Biology and Control)
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16 pages, 5858 KiB  
Article
A New Formulation for Strigolactone Suicidal Germination Agents, towards Successful Striga Management
by Muhammad Jamil, Jian You Wang, Djibril Yonli, Rohit H. Patil, Mohammed Riyazaddin, Prakash Gangashetty, Lamis Berqdar, Guan-Ting Erica Chen, Hamidou Traore, Ouedraogo Margueritte, Binne Zwanenburg, Satish Ekanath Bhoge and Salim Al-Babili
Plants 2022, 11(6), 808; https://doi.org/10.3390/plants11060808 - 18 Mar 2022
Cited by 16 | Viewed by 2646
Abstract
Striga hermonthica, a member of the Orobanchaceae family, is an obligate root parasite of staple cereal crops, which poses a tremendous threat to food security, contributing to malnutrition and poverty in many African countries. Depleting Striga seed reservoirs from infested soils is [...] Read more.
Striga hermonthica, a member of the Orobanchaceae family, is an obligate root parasite of staple cereal crops, which poses a tremendous threat to food security, contributing to malnutrition and poverty in many African countries. Depleting Striga seed reservoirs from infested soils is one of the crucial approaches to minimize subterranean damage to crops. The dependency of Striga germination on the host-released strigolactones (SLs) has prompted the development of the “Suicidal Germination” strategy to reduce the accumulated seed bank of Striga. The success of aforementioned strategy depends not only on the activity of the applied SL analogs, but also requires suitable application protocol with simple, efficient, and handy formulation for rain-fed African agriculture. Here, we developed a new formulation “Emulsifiable Concentration (EC)” for the two previously field-assessed SL analogs Methyl phenlactonoate 3 (MP3) and Nijmegen-1. The new EC formulation was evaluated for biological activities under lab, greenhouse, mini-field, and field conditions in comparison to the previously used Atlas G-1086 formulation. The EC formulation of SL analogs showed better activities on Striga germination with lower EC50 and high stability under Lab conditions. Moreover, EC formulated SL analogs at 1.0 µM concentrations reduced 89–99% Striga emergence in greenhouse. The two EC formulated SL analogs showed also a considerable reduction in Striga emergence in mini-field and field experiments. In conclusion, we have successfully developed a desired formulation for applying SL analogs as suicidal agents for large-scale field application. The encouraging results presented in this study pave the way for integrating the suicidal germination approach in sustainable Striga management strategies for African agriculture. Full article
(This article belongs to the Special Issue Parasitic Weeds: Biology and Control)
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10 pages, 1322 KiB  
Article
Germination Stimulant Activity of Isothiocyanates on Phelipanche spp.
by Hinako Miura, Ryota Ochi, Hisashi Nishiwaki, Satoshi Yamauchi, Xiaonan Xie, Hidemitsu Nakamura, Koichi Yoneyama and Kaori Yoneyama
Plants 2022, 11(5), 606; https://doi.org/10.3390/plants11050606 - 24 Feb 2022
Cited by 8 | Viewed by 1933
Abstract
The root parasitic weed broomrapes, Phelipanche spp., cause severe damage to agriculture all over the world. They have a special host-dependent lifecycle and their seeds can germinate only when they receive chemical signals released from host roots. Our previous study demonstrated that 2-phenylethyl [...] Read more.
The root parasitic weed broomrapes, Phelipanche spp., cause severe damage to agriculture all over the world. They have a special host-dependent lifecycle and their seeds can germinate only when they receive chemical signals released from host roots. Our previous study demonstrated that 2-phenylethyl isothiocyanate is an active germination stimulant for P. ramosa in root exudates of oilseed rape. In the present study, 21 commercially available ITCs were examined for P. ramosa seed germination stimulation, and some important structural features of ITCs for exhibiting P. ramosa seed germination stimulation have been uncovered. Structural optimization of ITC for germination stimulation resulted in ITCs that are highly active to P. ramosa. Interestingly, these ITCs induced germination of P. aegyptiaca but not Orobanche minor or Striga hermonthica. P. aegyptiaca seeds collected from mature plants parasitizing different hosts responded to these ITCs with different levels of sensitivity. ITCs have the potential to be used as inducers of suicidal germination of Phelipanche seeds. Full article
(This article belongs to the Special Issue Parasitic Weeds: Biology and Control)
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11 pages, 255 KiB  
Article
Evaluating Branched Broomrape (Phelipanche ramosa) Management Strategies in California Processing Tomato (Solanum lycopersicum)
by Matthew J. Fatino and Bradley D. Hanson
Plants 2022, 11(3), 438; https://doi.org/10.3390/plants11030438 - 05 Feb 2022
Cited by 2 | Viewed by 1470
Abstract
Detections of the regulated noxious parasitic weed branched broomrape (Phelipanche ramosa) in California tomato fields have led to interest in eradication, sanitation, and management practices. Researchers in Israel developed a decision-support system and herbicide treatment regime for management of Egyptian broomrape [...] Read more.
Detections of the regulated noxious parasitic weed branched broomrape (Phelipanche ramosa) in California tomato fields have led to interest in eradication, sanitation, and management practices. Researchers in Israel developed a decision-support system and herbicide treatment regime for management of Egyptian broomrape (P. aegyptiaca) in tomato. Research was conducted in 2019 and 2020 to evaluate whether similar treatments could be used to manage branched broomrape in California processing tomatoes and to provide registration support data for the herbicide use pattern. Treatment programs based on preplant incorporated (PPI) sulfosulfuron and chemigated imazapic were evaluated in 2019 and 2020 to determine safety on the processing tomato crop and on common rotational crops. Three single-season tomato safety experiments were conducted and a single rotational crop study was conducted in which a tomato crop received herbicide treatments in 2019 and several common rotational crops were planted and evaluated in 2020 in a site without branched broomrape. In 2020, an efficacy study was conducted in a commercial tomato field known to be infested with branched broomrape to evaluate the efficacy of PPI sulfosulfuron and chemigated imazapic, imazapyr, imazethapyr, and imazamox. After two field seasons, sulfosulfuron and imazapic appeared to have reasonable crop safety on tomato in California; however, rotational crop restrictions will need to be considered if sulfosulfuron is used to manage branched broomrape. In the efficacy study, there was a trend in which the sulfosulfuron and imidazolinone treatments had fewer broomrape shoots per plot than the grower standard treatments, however, none were fully effective and there were no significant differences among the various sulfosulfuron and imidazolinone treatment combinations. Additional research is needed to optimize the treatment timing for management of branched broomrape in this cropping system. Because of registration barriers with imazapic in the California market, future research will focus on treatment combinations of PPI sulfosulfuron and chemigated imazamox rather than imazapic. Full article
(This article belongs to the Special Issue Parasitic Weeds: Biology and Control)
13 pages, 38940 KiB  
Article
Mobile Host mRNAs Are Translated to Protein in the Associated Parasitic Plant Cuscuta campestris
by So-Yon Park, Kohki Shimizu, Jocelyn Brown, Koh Aoki and James H. Westwood
Plants 2022, 11(1), 93; https://doi.org/10.3390/plants11010093 - 28 Dec 2021
Cited by 11 | Viewed by 3019
Abstract
Cuscuta spp. are obligate parasites that connect to host vascular tissue using a haustorium. In addition to water, nutrients, and metabolites, a large number of mRNAs are bidirectionally exchanged between Cuscuta spp. and their hosts. This trans-specific movement of mRNAs raises questions about [...] Read more.
Cuscuta spp. are obligate parasites that connect to host vascular tissue using a haustorium. In addition to water, nutrients, and metabolites, a large number of mRNAs are bidirectionally exchanged between Cuscuta spp. and their hosts. This trans-specific movement of mRNAs raises questions about whether these molecules function in the recipient species. To address the possibility that mobile mRNAs are ultimately translated, we built upon recent studies that demonstrate a role for transfer RNA (tRNA)-like structures (TLSs) in enhancing mRNA systemic movement. C. campestris was grown on Arabidopsis that expressed a β-glucuronidase (GUS) reporter transgene either alone or in GUS-tRNA fusions. Histochemical staining revealed localization in tissue of C. campestris grown on Arabidopsis with GUS-tRNA fusions, but not in C. campestris grown on Arabidopsis with GUS alone. This corresponded with detection of GUS transcripts in Cuscuta on Arabidopsis with GUS-tRNA, but not in C. campestris on Arabidopsis with GUS alone. Similar results were obtained with Arabidopsis host plants expressing the same constructs containing an endoplasmic reticulum localization signal. In C. campestris, GUS activity was localized in the companion cells or phloem parenchyma cells adjacent to sieve tubes. We conclude that host-derived GUS mRNAs are translated in C. campestris and that the TLS fusion enhances RNA mobility in the host-parasite interactions. Full article
(This article belongs to the Special Issue Parasitic Weeds: Biology and Control)
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14 pages, 1895 KiB  
Article
Trophic Transfer without Biomagnification of Cadmium in a Soybean-Dodder Parasitic System
by Bin J. W. Chen, Jing Xu and Xinyu Wang
Plants 2021, 10(12), 2690; https://doi.org/10.3390/plants10122690 - 07 Dec 2021
Cited by 3 | Viewed by 2391
Abstract
Cadmium (Cd) is among the most available and most toxic heavy metals taken up by plants from soil. Compared to the classic plant-animal food chains, the host-parasitic plant food chains have, thus far, been largely overlooked in the studies of Cd trophic transfer. [...] Read more.
Cadmium (Cd) is among the most available and most toxic heavy metals taken up by plants from soil. Compared to the classic plant-animal food chains, the host-parasitic plant food chains have, thus far, been largely overlooked in the studies of Cd trophic transfer. To investigate the pattern of Cd transfer during the infection of parasitic plants on Cd-contaminated hosts, we conducted a controlled experiment that grew soybeans parasitized by Chinese dodders (Cuscuta chinensis) in soil with different levels of Cd treatment, and examined the concentration, accumulation, allocation and transfer coefficients of Cd within this parasitic system. Results showed that among all components, dodders accounted for more than 40% biomass of the whole system but had the lowest Cd concentration and accumulated the least amount of Cd. The transfer coefficient of Cd between soybean stems and dodders was much lower than 1, and was also significantly lower than that between soybean stems and soybean leaves. All these features were continuously strengthened with the increase of Cd treatment levels. The results suggested no evidence of Cd biomagnification in dodders parasitizing Cd-contaminated hosts, and implied that the Cd transfer from hosts to dodders may be a selective process. Full article
(This article belongs to the Special Issue Parasitic Weeds: Biology and Control)
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14 pages, 1908 KiB  
Article
Characterization of a Chickpea Mutant Resistant to Phelipanche aegyptiaca Pers. and Orobanche crenata Forsk
by Shmuel Galili, Joseph Hershenhorn, Evgeny Smirnov, Koichi Yoneyama, Xiaonan Xie, Orit Amir-Segev, Aharon Bellalou and Evgenia Dor
Plants 2021, 10(12), 2552; https://doi.org/10.3390/plants10122552 - 23 Nov 2021
Cited by 6 | Viewed by 1840
Abstract
Chickpea (Cicer arietinum L.) is a major pulse crop in Israel grown on about 3000 ha spread, from the Upper Galilee in the north to the North-Negev desert in the south. In the last few years, there has been a gradual increase [...] Read more.
Chickpea (Cicer arietinum L.) is a major pulse crop in Israel grown on about 3000 ha spread, from the Upper Galilee in the north to the North-Negev desert in the south. In the last few years, there has been a gradual increase in broomrape infestation in chickpea fields in all regions of Israel. Resistant chickpea cultivars would be simple and effective solution to control broomrape. Thus, to develop resistant cultivars we screened an ethyl methanesulfonate (EMS) mutant population of F01 variety (Kabuli type) for broomrape resistance. One of the mutant lines (CCD7M14) was found to be highly resistant to both Phelipanche aegyptiaca and Orobanche crenata. The resistance mechanism is based on the inability of the mutant to produce strigolactones (SLs)—stimulants of broomrape seed germination. LC/MS/MS analysis revealed the SLs orobanchol, orobanchyl acetate, and didehydroorobanchol in root exudates of the wild type, but no SLs could be detected in the root exudates of CCD7M14. Sequence analyses revealed a point mutation (G-to-A transition at nucleotide position 210) in the Carotenoid Cleavage Dioxygenase 7 (CCD7) gene that is responsible for the production of key enzymes in the biosynthesis of SLs. This nonsense mutation resulted in a CCD7 stop codon at position 70 of the protein. The influences of the CCD7M14 mutation on chickpea phenotype and chlorophyll, carotenoid, and anthocyanin content were characterized. Full article
(This article belongs to the Special Issue Parasitic Weeds: Biology and Control)
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13 pages, 2147 KiB  
Article
The Effect of a Host on the Primary Metabolic Profiling of Cuscuta Campestris’ Main Organs, Haustoria, Stem and Flower
by Krishna Kumar and Rachel Amir
Plants 2021, 10(10), 2098; https://doi.org/10.3390/plants10102098 - 03 Oct 2021
Cited by 7 | Viewed by 2005
Abstract
Cuscuta campestris (dodder) is a stem holoparasitic plant without leaves or roots that parasitizes various types of host plants and causes damage to certain crops worldwide. This study aimed at gaining more knowledge about the effect of the hosts on the parasite’s levels [...] Read more.
Cuscuta campestris (dodder) is a stem holoparasitic plant without leaves or roots that parasitizes various types of host plants and causes damage to certain crops worldwide. This study aimed at gaining more knowledge about the effect of the hosts on the parasite’s levels of primary metabolites. To this end, metabolic profiling analyses were performed on the parasite’s three main organs, haustoria, stem and flowers, which developed on three hosts, Heliotropium hirsutissimum, Polygonum equisetiforme and Amaranthus viridis. The results showed significant differences in the metabolic profiles of C. campestris that developed on the different hosts, suggesting that the parasites rely highly on the host’s metabolites. However, changes in the metabolites’ contents between the organs that developed on the same host suggest that the parasite can also self-regulate its metabolites. Flowers, for example, have significantly higher levels of most of the amino acids and sugar acids, while haustoria and stem have higher levels of several sugars and polyols. Determination of total soluble proteins and phenolic compounds showed that the same pattern is detected in the organs unrelated to the hosts. This study contributes to our knowledge about the metabolic behavior of this parasite. Full article
(This article belongs to the Special Issue Parasitic Weeds: Biology and Control)
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14 pages, 11440 KiB  
Article
Biological and Transcriptomic Characterization of Pre-Haustorial Resistance to Sunflower Broomrape (Orobanche cumana W.) in Sunflowers (Helianthus annuus)
by Dana Sisou, Yaakov Tadmor, Dina Plakhine, Hammam Ziadna, Sariel Hübner and Hanan Eizenberg
Plants 2021, 10(9), 1810; https://doi.org/10.3390/plants10091810 - 30 Aug 2021
Cited by 7 | Viewed by 2787
Abstract
Infestations with sunflower broomrape (Orobanche cumana Wallr.), an obligatory root parasite, constitute a major limitation to sunflower production in many regions around the world. Breeding for resistance is the most effective approach to reduce sunflower broomrape infestation, yet resistance mechanisms are often [...] Read more.
Infestations with sunflower broomrape (Orobanche cumana Wallr.), an obligatory root parasite, constitute a major limitation to sunflower production in many regions around the world. Breeding for resistance is the most effective approach to reduce sunflower broomrape infestation, yet resistance mechanisms are often broken by new races of the pathogen. Elucidating the mechanisms controlling resistance to broomrape at the molecular level is, thus, a desirable way to obtain long-lasting resistance. In this study, we investigated broomrape resistance in a confectionery sunflower cultivar with a robust and long-lasting resistance to sunflower broomrape. Visual screening and histological examination of sunflower roots revealed that penetration of the broomrape haustorium into the sunflower roots was blocked at the cortex, indicating a pre-haustorial mechanism of resistance. A comparative RNA sequencing between broomrape-resistant and -susceptible accessions allowed the identification of genes that were significantly differentially expressed upon broomrape infestation. Among these genes were β-1,3-endoglucanase, β-glucanase, and ethylene-responsive transcription factor 4 (ERF4). These genes were previously reported to be pathogenesis-related in other plant species. This transcriptomic investigation, together with the histological examinations, led us to conclude that the resistance mechanism involves the identification of the broomrape and the consequent formation of a physical barrier that prevents the establishment of the broomrape into the sunflower roots. Full article
(This article belongs to the Special Issue Parasitic Weeds: Biology and Control)
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11 pages, 1400 KiB  
Article
Imazapic Herbigation for Egyptian Broomrape (Phelipanche aegyptiaca) Control in Processing Tomatoes—Laboratory and Greenhouse Studies
by Yaakov Goldwasser, Onn Rabinovitz, Zev Gerstl, Ahmed Nasser, Amit Paporisch, Hadar Kuzikaro, Moshe Sibony and Baruch Rubin
Plants 2021, 10(6), 1182; https://doi.org/10.3390/plants10061182 - 10 Jun 2021
Cited by 5 | Viewed by 3047
Abstract
Parasitic plants belonging to the Orobanchaceae family include species that cause heavy damage to crops in Mediterranean climate regions. Phelipanche aegyptiaca is the most common of the Orobanchaceae species in Israel inflicting heavy damage to a wide range of broadleaf crops, including processing [...] Read more.
Parasitic plants belonging to the Orobanchaceae family include species that cause heavy damage to crops in Mediterranean climate regions. Phelipanche aegyptiaca is the most common of the Orobanchaceae species in Israel inflicting heavy damage to a wide range of broadleaf crops, including processing tomatoes. P. aegyptiaca is extremely difficult to control due to its minute and vast number of seeds and its underground association with host plant roots. The highly efficient attachment of the parasite haustoria into the host phloem and xylem enables the diversion of water, assimilates and minerals from the host into the parasite. Drip irrigation is the most common method of irrigation in processing tomatoes in Israel, but the delivery of herbicides via drip irrigation systems (herbigation) has not been thoroughly studied. The aim of these studies was to test, under laboratory and greenhouse conditions, the factors involved in the behavior of soil-herbigated imazapic, and the consequential influence of imazapic on P. aegyptiaca and tomato plants. Dose-response Petri dish studies showed that imazapic does not impede P. aegyptiaca seed germination and non-attached seedlings, even at the high rate of 5000 ppb. Imazapic applied to tomato roots inoculated with P. aegyptiaca seeds in a PE bag system revealed that the parasite is killed only after its attachment to the tomato roots, at concentrations as low as 2.5 ppb. Imazapic sorption curves and calculated Kd and Koc values indicated that the herbicide Kd is similar in all soils excluding a two-fold higher coefficient in the Gadash farm soil, while the Koc was similar in all soils except the Eden farm soil, in which it was more than twofold lower. In greenhouse studies, control of P. aegyptiaca was achieved at >2.5 ppb imazapic, but adequate control requires repeated applications due to the 7-day half-life (t1/2) of the herbicide in the soil. Tracking of imazapic in soil and tomato roots revealed that the herbicide accumulates in the tomato host plant roots, but its movement to newly formed roots is limited. The data obtained in the laboratory and greenhouse studies provide invaluable knowledge for devising field imazapic application strategies via drip irrigation systems for efficient and selective broomrape control. Full article
(This article belongs to the Special Issue Parasitic Weeds: Biology and Control)
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Other

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9 pages, 1337 KiB  
Opinion
A Personal History in Parasitic Weeds and Their Control
by Chris Parker
Plants 2021, 10(11), 2249; https://doi.org/10.3390/plants10112249 - 21 Oct 2021
Cited by 3 | Viewed by 1735
Abstract
This invited paper summarises a career in which I became increasingly involved in research and related activities on Striga and other parasitic weeds. It also presents a personal view of the present status of parasitic weed problems and their control. Full article
(This article belongs to the Special Issue Parasitic Weeds: Biology and Control)
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