Modulation of host plant immunity by Tobamovirus proteins

Powdery mildew causes substantial losses in crop and economic plant yields worldwide. Although powdery mildew infection of rubber trees (Hevea brasiliensis), caused by the biotrophic fungus Erysiphe quercicola, severely threatens natural rubber production, little is known regarding the mechanism by which E. quercicola adapts to H. brasiliensis to invade the host plant. In barley and Arabidopsis thaliana, lifeguard (LFG) proteins, which have topological similarity to BAX INHIBITOR-1, are involved in host plant susceptibility to powdery mildew infection. In this study, we characterized an H. brasiliensis LFG protein, HbLFG1, with a focus on its function in regulating defence against powdery mildew. HbLFG1 gene expression was found to be upregulated during E. quercicola infection. HbLFG1 showed conserved functions in cell death inhibition and membrane localization. Expression of HbLFG1 in Nicotiana benthamiana leaves and A. thaliana Col-0 was demonstrated to significantly suppress callose deposition induced by conserved pathogen-associated molecular patterns chitin and flg22. Furthermore, we found that overexpression of HbLFG1 in H. brasiliensis mesophyll protoplasts significantly suppressed the chitin-induced burst of reactive oxygen species. Although A. thaliana Col-0 and E. quercicola displayed an incompatible interaction, Col-0 transformants overexpressing HbLFG1 were shown to be susceptible to E. quercicola. Collectively, the findings of this study provide evidence that HbLFG1 acts as a negative regulator of plant immunity that facilitates E. quercicola infection in H. brasiliensis.

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OBSERVATIONS ON HOST PLANT INDUCED BEHAVIOR OF SCALE INSECTS AND THEIR ENDOPARASITES

The Canadian Entomologist ◽

10.4039/ent102913-8 ◽

1970 ◽

Vol 102 (8) ◽

pp. 913-926 ◽

Cited By ~ 11

Author(s):

S. E. Flanders

Keyword(s):

Host Plant ◽

Physiological Response ◽

Host Plants ◽

Plant Immunity ◽

Scale Insects ◽

Great Abundance ◽

Edaphic Conditions ◽

Saissetia Oleae ◽

Induced Immunity ◽

Host Regulation

AbstractDifferences in the behavior of scale insects induced by their host plants has been observed, principally, in uniparental, bisexual, univoltine species. Behavior in endoparasites of such species also may be thus modified. The phenomena involved, reproductivity, sexuality, voltinism and, with the parasites, host-regulation, are related to the environmentally induced immunity of the host plant to its indigenous scale insects.This immunity, when not a regional phenomenon, is necessarily sporadic. When operative, it may he as complete as generic-immunity. Periodic host plant non-susceptibility is considered to he a physiological response to meteorological and edaphic conditions, a response usually rendering the plant temporarily unsuitable for coccid development. The interpolation of immune periods in the life of a coccid’s normal host plant necessarily disrupts the continuity of the host-regulative action of the coccid’s parasites. Host plant pheno-immunity was first clearly manifested in regions where Lecanium corni Bouché, L. tiliae (Linnaeus), and Saissetia oleae (Bernard) free of their regulative parasites, reproduced in great abundance. In regions to which these coccids are indigenous the limitation of their outbreaks to artificial monocultures attested to the obscure nature of host plant pheno-immunity. The cessation of host plant immunity to coccids, the subsequent heavy reinfestation, and then the parasitic elimination of the outbreak attested to the host-regulative power of parasitization.

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Multiple immunity-related genes control susceptibility of Arabidopsis thaliana to the parasitic weed Phelipanche aegyptiaca

PeerJ ◽

10.7717/peerj.9268 ◽

2020 ◽

Vol 8 ◽

pp. e9268

Author(s):

Christopher R. Clarke ◽

So-Yon Park ◽

Robert Tuosto ◽

Xiaoyan Jia ◽

Amanda Yoder ◽

...

Keyword(s):

Arabidopsis Thaliana ◽

Host Plant ◽

Plant Immunity ◽

Parasitic Weed ◽

Hub Gene ◽

Host Genetic ◽

Viable Approach ◽

Mutant Lines ◽

Host Genes ◽

Plant Susceptibility

Parasitic weeds represent a major threat to agricultural production across the world. Little is known about which host genetic pathways determine compatibility for any host–parasitic plant interaction. We developed a quantitative assay to characterize the growth of the parasitic weed Phelipanche aegyptiaca on 46 mutant lines of the host plant Arabidopsis thaliana to identify host genes that are essential for susceptibility to the parasite. A. thaliana host plants with mutations in genes involved in jasmonic acid biosynthesis/signaling or the negative regulation of plant immunity were less susceptible to P. aegyptiaca parasitization. In contrast, A. thaliana plants with a mutant allele of the putative immunity hub gene Pfd6 were more susceptible to parasitization. Additionally, quantitative PCR revealed that P. aegyptiaca parasitization leads to transcriptional reprograming of several hormone signaling pathways. While most tested A. thaliana lines were fully susceptible to P. aegyptiaca parasitization, this work revealed several host genes essential for full susceptibility or resistance to parasitism. Altering these pathways may be a viable approach for limiting host plant susceptibility to parasitism.

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SHR4z, a novel decoy effector from the haustorium of the parasitic weed Striga gesnerioides, suppresses host plant immunity

New Phytologist ◽

10.1111/nph.16351 ◽

2020 ◽

Vol 226 (3) ◽

pp. 891-908 ◽

Cited By ~ 5

Author(s):

Chun Su ◽

Hai Liu ◽

Eric K. Wafula ◽

Loren Honaas ◽

Claude W. Pamphilis ◽

...

Keyword(s):

Host Plant ◽

Plant Immunity ◽

Parasitic Weed ◽

Striga Gesnerioides

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Plant immunity: Born to cheat

Nature China ◽

10.1038/nchina.2008.16 ◽

2008 ◽

Author(s):

Wei Zeng

Keyword(s):

Plant Immunity

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Mango: A new host plant for the lycaeinid Anthene lycaenina lycaenina (R. Felder, 1868)

ENTOMON ◽

10.33307/entomon.v45i3.556 ◽

2020 ◽

Vol 45 (3) ◽

pp. 237-238

Author(s):

J. Nayanathara ◽

R. Narayana

Keyword(s):

Host Plant ◽

New Host ◽

First Time

Anthene lycaenina lycaenina (R. Felder, 1868) is reported on mango for the first time.

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The description of a new Bruchophagus species (Hymenoptera, Chalcidoidea, Eurytomidae) developing in seeds of Melilotus officinalis (L.) Descr. (Fabaceae) in Iran

Ukrainian Entomological Journal ◽

10.15421/281902 ◽

2019 ◽

Vol 16 (1) ◽

pp. 12-15

Author(s):

M.D. Zerova ◽

A. Al-Sendi ◽

V.N. Fursov ◽

H. Adeli-Manesh ◽

S.E. Sadeghi ◽

...

Keyword(s):

New Species ◽

Host Plant ◽

Lotus Corniculatus ◽

Lateral View ◽

National Academy Of Sciences ◽

Melilotus Officinalis ◽

Biological Features ◽

Academy Of Sciences

The new species, Bruchophagus ayadi sp.n., is reared from seed pods of Melilotus officinalis (L.) Desr. (Fabaceae) in Iran (Lorestan). The new species is close to B. platypterus (Walk.), but differs by roundish abdomen and very gibbous, almost globular (in lateral view) mesosoma. These species can be also differentiated by some biological features. The host plant of B. platypterus is Lotus corniculatus L., whereas the new species is reared from Melilotus officinalis (L.) Desr. Holotype of Bruchophagus ayadi sp.n. is deposited in the collection of I.I. Schmalhausen Institute of Zoology of National Academy of Sciences of Ukraine (Kyiv).

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