A New Concept for Multiple Resistance Breeding in Wheat to Leaf and Ear Diseases

AbstractXanthomonas campestris pv. campestris, the causal agent of black rot of crucifers, was one of the first bacterial plant pathogens ever identified. Over 130 years later, black rot remains a threat to cabbage, cauliflower, and other Brassica crops around the world. Recent genomic and genetic data are informing our understanding of X. campestris taxonomy, dissemination, inoculum sources, and virulence factors. This new knowledge promises to positively impact resistance breeding of Brassica varieties and management of inoculum sources.

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Morphological and Chemical Factors Related to Western Flower Thrips Resistance in the Ornamental Gladiolus

Plants ◽

10.3390/plants10071384 ◽

2021 ◽

Vol 10 (7) ◽

pp. 1384

Author(s):

Dinar S. C. Wahyuni ◽

Young Hae Choi ◽

Kirsten A. Leiss ◽

Peter G. L. Klinkhamer

Keyword(s):

Host Plant ◽

Plant Resistance ◽

Host Plant Resistance ◽

Frankliniella Occidentalis ◽

Western Flower Thrips ◽

Resistance Breeding ◽

Breeding Programs ◽

Triterpenoid Saponins ◽

Flower Thrips ◽

Highly Correlated

Understanding the mechanisms involved in host plant resistance opens the way for improved resistance breeding programs by using the traits involved as markers. Pest management is a major problem in cultivation of ornamentals. Gladiolus (Gladiolus hybridus L.) is an economically important ornamental in the Netherlands. Gladiolus is especially sensitive to attack by western flower thrips (Frankliniella occidentalis (Pergande) (Thysanoptera:Thripidae)). The objective of this study was, therefore, to investigate morphological and chemical markers for resistance breeding to western flower thrips in Gladiolus varieties. We measured thrips damage of 14 Gladiolus varieties in a whole-plant thrips bioassay and related this to morphological traits with a focus on papillae density. Moreover, we studied chemical host plant resistance to using an eco-metabolomic approach comparing the 1H NMR profiles of thrips resistant and susceptible varieties representing a broad range of papillae densities. Thrips damage varied strongly among varieties: the most susceptible variety showed 130 times more damage than the most resistant one. Varieties with low thrips damage had shorter mesophylls and epidermal cells, as well as a higher density of epicuticular papillae. All three traits related to thrips damage were highly correlated with each other. We observed a number of metabolites related to resistance against thrips: two unidentified triterpenoid saponins and the amino acids alanine and threonine. All these compounds were highly correlated amongst each other as well as to the density of papillae. These correlations suggest that papillae are involved in resistance to thrips by producing and/or storing compounds causing thrips resistance. Although it is not possible to distinguish the individual effects of morphological and chemical traits statistically, our results show that papillae density is an easy marker in Gladiolus-breeding programs targeted at increased resistance to thrips.

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Search for Resistant Genotypes to Cuscuta campestris Infection in Two Legume Species, Vicia sativa and Vicia ervilia

Plants ◽

10.3390/plants10040738 ◽

2021 ◽

Vol 10 (4) ◽

pp. 738

Author(s):

Eva María Córdoba ◽

Mónica Fernández-Aparicio ◽

Clara Isabel González-Verdejo ◽

Carmela López-Grau ◽

María del Valle Muñoz-Muñoz ◽

...

Keyword(s):

Agricultural Production ◽

Host Plants ◽

Resistance Breeding ◽

Parasitic Plants ◽

Vicia Sativa ◽

Common Vetch ◽

Germplasm Collections ◽

Bitter Vetch ◽

Cuscuta Campestris ◽

Resistant Genotypes

The dodders (Cuscuta spp.) are parasitic plants that feed on the stems of their host plants. Cuscuta campestris is one of the most damaging parasitic plants for the worldwide agricultural production of broad-leaved crops. Its control is limited or non-existent, therefore resistance breeding is the best alternative both economically and environmentally. Common vetch (Vicia sativa) and bitter vetch (Vicia ervilia) are highly susceptible to C. campestris, but no resistant genotypes have been identified. Thus, the aim of this study was to identify in V. sativa and V.ervilia germplasm collections genotypes resistant to C. campestris infection for use in combating this parasitic plant. Three greenhouse screening were conducted to: (1) identify resistant responses in a collection of 154 accessions of bitter vetch and a collection of 135 accessions of common vetch genotypes against infection of C. campestris; (2) confirm the resistant response identified in common vetch accessions; and (3) characterize the effect of C. campestris infection on biomass of V. sativa resistant and susceptible accessions. Most common vetch and bitter vetch genotypes tested were susceptible to C. campestris. However, the V. sativa genotype Vs.1 exhibited high resistance. The resistant phenotype was characterized by a delay in the development of C. campestris posthaustorial growth and a darkening resembling a hypersensitive-like response at the penetration site. The resistant mechanism was effective in limiting the growth of C. campestris as the ratio of parasite/host shoot dry biomass was more significantly reduced than the rest of the accessions. To the best or our knowledge, this is the first identification of Cuscuta resistance in V. sativa genotypes.

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Ultrasound Microbubbles Enhance the Efficacy of Insulin-Like Growth Factor-1 Therapy for the Treatment of Noise-Induced Hearing Loss

Molecules ◽

10.3390/molecules26123626 ◽

2021 ◽

Vol 26 (12) ◽

pp. 3626

Author(s):

Yi-Chun Lin ◽

Yuan-Yung Lin ◽

Hsin-Chien Chen ◽

Chao-Yin Kuo ◽

Ai-Ho Liao ◽

...

Keyword(s):

Hearing Loss ◽

Growth Factor ◽

Inner Ear ◽

Outer Hair Cells ◽

Round Window Membrane ◽

Insulin Like Growth Factor ◽

Noise Induced Hearing Loss ◽

Ear Diseases ◽

Brainstem Response ◽

Ultrasound Microbubbles

The application of insulin-like growth factor 1 (IGF-1) to the round window membrane (RWM) is an emerging treatment for inner ear diseases. RWM permeability is the key factor for efficient IGF-1 delivery. Ultrasound microbubbles (USMBs) can increase drug permeation through the RWM. In the present study, the enhancing effect of USMBs on the efficacy of IGF-1 application and the treatment effect of USMB-mediated IGF-1 delivery for noise-induced hearing loss (NIHL) were investigated. Forty-seven guinea pigs were assigned to three groups: the USM group, which received local application of recombinant human IGF-1 (rhIGF-1, 10 µg/µL) following application of USMBs to the RWM; the RWS group, which received IGF-1 application alone; and the saline-treated group. The perilymphatic concentration of rhIGF-1 in the USM group was 1.95- and 1.67- fold of that in the RWS group, 2 and 24 h after treatment, respectively. After 5 h of 118 dB SPL noise exposure, the USM group had the lowest threshold shift in auditory brainstem response, least loss of cochlear outer hair cells, and least reduction in the number of synaptic ribbons on postexposure day 28 among the three groups. The combination of USMB and IGF-1 led to a better therapeutic response to NIHL. Two hours after treatment, the USM group had significantly higher levels of Akt1 and Mapk3 gene expression than the other two groups. The most intense immunostaining for phosphor-AKT and phospho-ERK1/2 was detected in the cochlea in the USM group. These results suggested that USMB can be applied to enhance the efficacy of IGF-1 therapy in the treatment of inner ear diseases.

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Evaluation of breeding potential of wild grape originating from Armenia

BIO Web of Conferences ◽

10.1051/bioconf/20191501006 ◽

2019 ◽

Vol 15 ◽

pp. 01006

Author(s):

K. Margaryan ◽

E. Maul ◽

Z. Muradyan ◽

A. Hovhannisyan ◽

G. Melyan ◽

...

Keyword(s):

Vitis Vinifera ◽

Allelic Variation ◽

Resistance Breeding ◽

Crop Wild Relatives ◽

Breeding Programs ◽

Genetic Traits ◽

Breeding Potential ◽

Wild Grape ◽

Wild Grapevine ◽

The Future

Crop wild relatives provide a useful source of genetic variation and represent a large pool of genetic diversity for new allelic variation required in breeding programs. Armenia is an important center of origin both for cultivated Vitis vinifera ssp. sativa and wild Vitis vinifera ssp. sylvestris. Owing to recent prospection in Armenian woods and river floodplains many forms of wild grapevine were discovered and inventoried, which is an important prerequisite to unlock their breeding potential in the future. The fact that some genotypes of V. sylvestris can withstand the diseases is likely to be due to a more efficient basal immunity. The overall goal of the proposed research was to characterize the diversity of V. sylvestris from Armenia with respect to its capacity for stilbene biosynthesis, which might be exploited as genetic resource for resistance breeding. The realized research stimulates the recovery, characterization and preservation of wild grape germplasm, presently at risk of extinction. The recovery and characterization of wild genotypes will be the base of selection of genetic traits important in breeding programs for the generation of biotic and changing climate tolerant grapevine varieties and rootstocks, both necessary for the future of viticulture in Armenia and in Europe.

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