Prohexadione calcium is herbicidal to the sunflower root parasite Orobanche cumana

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.

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Biological and Transcriptomic Characterization of Pre-haustorial Resistance to Sunflower Broomrape (Orobanche cumana W.)

10.1101/2021.02.17.431739 ◽

2021 ◽

Author(s):

Dana Sisou ◽

Yaakov Tadmor ◽

Dina Plakhine ◽

Sariel Hübner ◽

Hanan Eizenberg

Keyword(s):

Resistance Mechanism ◽

Resistance Mechanisms ◽

Differentially Expressed ◽

Orobanche Cumana ◽

Resistant Lines ◽

Pathogenesis Related ◽

Root Parasite ◽

Sunflower Broomrape ◽

New Races

AbstractInfestations 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 overcome by new races of the pathogen. Elucidating the mechanisms controlling the resistance to broomrape at the molecular level is thus the most desirable pathway to obtaining long-lasting resistance and reducing yield loss in sunflower. In this study, we investigated broomrape resistance in a confectionery sunflower hybrid with a robust and long-lasting resistance to sunflower broomrape. Visual screening and histological examination of sunflower roots revealed that penetration of the intrusive broomrape cells into the host root endodermis is blocked at the host cortex, indicating a pre-haustorial mechanism of resistance. A comparative RNA-Seq experiment conducted between roots obtained from the resistant cultivar, a bulk of five broomrape resistant lines and a bulk of five broomrape susceptible lines allowed the identification of genes that were significantly differentially expressed upon broomrape infestation. Among these differentially expressed genes, β-1,3-endoglucanase, β-glucanase and ethylene-responsive transcription factor4 (ERF4) genes were identified. These genes were previously reported to be pathogenesis-related genes in other plant species. This genetics 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 penetration of the broomrape into the sunflower roots.

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The obligate root parasite Orobanche cumana exhibits several rbcL sequences

Gene ◽

10.1016/s0378-1119(02)00868-5 ◽

2002 ◽

Vol 297 (1-2) ◽

pp. 85-92 ◽

Cited By ~ 19

Author(s):

Philippe Delavault ◽

Patrick Thalouarn

Keyword(s):

Orobanche Cumana ◽

Root Parasite ◽

Rbcl Sequences

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Orobanche cumana (sunflower broomrape).

10.1079/cpc.37745.20210102251 ◽

2021 ◽

Author(s):

Chris Parker

Keyword(s):

South America ◽

Eastern Europe ◽

Helianthus Annuus ◽

Western Europe ◽

Orobanche Cumana ◽

Winter Temperatures ◽

Root Parasite ◽

Sunflower Broomrape

Abstract O. cumana is an obligatory, non-photosynthetic root parasite. It is believed to have evolved relatively recently from forms of O. cernua parasitizing wild Asteraceae, in particular species of Artemisia, and transferring to cultivated Helianthus annuus (sunflower). O. cumana is thought to be native to Eastern Europe (Russia) and has subsequently spread to most other sunflower growing regions of central and western Europe and Asia. The absence of O. cumana in sunflower growing regions of South America (for example Argentina) is believed to be associated with warmer winter temperatures not suitable for this species, rather than the seeds not being present. O. cumana can cause immense damage to cultivated sunflowers resulting in a significant decrease in yield. Despite resistant sunflower varieties being developed more virulent races of O. cumana have repeatedly evolved, or been selected, to overcome resistance. Thus, in spite of constant breeding efforts, losses continue in established sunflower growing areas and there is potential for it to invade new areas, wherever sunflower is grown.

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Dehydrocostus lactone is exuded from sunflower roots and stimulates germination of the root parasite Orobanche cumana

Phytochemistry ◽

10.1016/j.phytochem.2011.01.037 ◽

2011 ◽

Vol 72 (7) ◽

pp. 624-634 ◽

Cited By ~ 72

Author(s):

Daniel M. Joel ◽

Swapan K. Chaudhuri ◽

Dina Plakhine ◽

Hammam Ziadna ◽

John C. Steffens

Keyword(s):

Orobanche Cumana ◽

Root Parasite ◽

Dehydrocostus Lactone

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DETERMINATION OF AFTER-RIPENING PERIOD AND HORMONAL RESPONSE OF OROBANCHE SOLMSII C.D. CLARKE SEEDS

Ecoprint An International Journal of Ecology ◽

10.3126/eco.v11i1.149 ◽

1970 ◽

Vol 11 (1) ◽

Author(s):

A. Bista ◽

G. B. Khattri ◽

B. D. Acharya ◽

S. C. Srivastava

Keyword(s):

Growth Hormone ◽

Seed Germination ◽

Key Words ◽

Incubation Period ◽

Seed Set ◽

Summer Season ◽

Conditioning Period ◽

Root Parasite ◽

One Year

To find out the ability of Orobanche seeds to germinate immediately after seed set, seeds were germinated periodically at an interval of three months for one year in GR24. Some Orobanche seeds were capable of germination immediately after seed set but most required about nine months as after ripening or incubation period to be able to germinate. The phenomenon of after ripening in Orobanche seeds could be taken as an ecological measure to dormant over following unfavorable wet summer season. The growth hormone studies on Orobanche seed germination have shown that GA3 at a concentration of 100 ppm substantially enhanced seed germination when applied during pre-conditioning period. NAA showed some stimulatory effect at 0.5 - 1.0 ppm when applied during post-conditioning period but the hormone if applied during pre-conditioning period inhibited the germination. Kinetin failed to stimulate the germination at all the concentrations tested. Key words: Germination, root-parasite, hormone. Ecoprint Vol.11(1) 2004.

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Economic Impact of Prohexadione Calcium for Managing Vine Growth in Runner Market‐Type Peanut

Crops & Soils ◽

10.1002/crso.20126 ◽

2021 ◽

Author(s):

W. Scott Monfort ◽

R. Scott Tubbs

Keyword(s):

Economic Impact ◽

Vine Growth ◽

Prohexadione Calcium

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The Dwarfing Effects of Different Plant Growth Retardants on Magnolia wufengensis L.Y. Ma et L. R. Wang

Forests ◽

10.3390/f12010019 ◽

2020 ◽

Vol 12 (1) ◽

pp. 19

Author(s):

Xiaodeng Shi ◽

Siyu Chen ◽

Zhongkui Jia

Keyword(s):

Plant Growth ◽

Soluble Sugar ◽

Control Group ◽

Growth Retardants ◽

Sod Activity ◽

Node Number ◽

Plant Growth Retardants ◽

One Year ◽

Prohexadione Calcium ◽

Magnolia Wufengensis

The effects of varieties, concentrations, and number of applications of plant growth retardants (PGRs) on the morphological, physiological, and endogenous hormones of Magnolia wufengensis L.Y. Ma et L. R. Wang were assessed to obtain the most suitable dwarfing protocol for M. wufengensis and to provide theoretical support and technical guidance for the cultivation and promotion of this species. One-year-old M. wufengensis ‘Jiaohong No. 2’ grafted seedlings served as the experimental materials. In the first part of the experiment, three PGRs (uniconazole, paclobutrazol, prohexadione calcium), three concentrations (500, 1000, 1500 ppm), and three applications (one, three, and five applications) were applied in dwarfing experiments to perform L9 (34) orthogonal tests. In the second part of the study, dwarfing experiments were supplemented with different high uniconazole concentrations (0, 1500, 2000, 2500 ppm). Spraying 1500 ppm uniconazole five times achieved the best M. wufengensis dwarfing effect, related indicators of M. wufengensis under this treatment were better than other treatment combinations. Here, M. wufengensis plant height, internode length, scion diameter, and node number were significantly reduced by 56.9%, 62.6%, 72.8%, and 74.4%, respectively, compared with the control group. This treatment increased superoxide dismutase (SOD) activity by 66.0%, peroxidase (POD) activity by 85.0%, soluble protein contents by 43.3%, and soluble sugar contents by 27.6%, and reduced malondialdehyde (MDA) contents by 32.1% in leaves of M. wufengensis compared with the control. The stress resistance of M. wufengensis was enhanced. The treatment also reduced gibberellin (GA3) levels by 73.0%, auxin (IAA) by 58.0%, and zeatin (ZT) by 70.6%, and increased (abscisic acid) ABA by 98.1% in the leaves of M. wufengensis. The uniconazole supplementation experiment also showed that 1500 ppm was the optimal uniconazole concentration. The leaves exhibited abnormalities such as crinkling or adhesion when 2000 or 2500 ppm was applied. Given the importance of morphological indicators and dwarfing for the ornamental value of M. wufengensis, the optimal dwarfing treatment for M. wufengensis was spraying 1500 ppm uniconazole five times.

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