Fine genetic mapping of a quantitative trait locus involved in A.thaliana response to TuMV (Turnip mosaic virus)

Fine genetic mapping of a quantitative trait locus involved in A.thaliana response to TuMV ([i]Turnip mosaic virus[/i]). 16. Rencontres de Virologie Végétale (RVV 2017

Fine genetic mapping of a quantitative trait locus involved in A.thaliana response to TuMV (Turnip mosaic virus)

Fine genetic mapping of a quantitative trait locus involved in A.thaliana response to TuMV ([i]Turnip mosaic virus[/i]). 16. Rencontres de Virologie Végétale (RVV 2017

Analyse transcriptionnelle et approche "gènes candidats" pour l'étude des interactions Prunus/Plum pox potyvirus

National audienc

Elicitor-induced in vitro shoot multiplication and steviol glycosides production in Stevia rebaudiana

Stevia rebaudiana, which produces the non-caloric natural sweeteners referred to as steviol glycosides (SGs), is a perennial herb native to South America. This study examines the effect of various biotic elicitors, including chitosan (CH) and yeast extract (YE), as well one abiotic elicitor, namely methyl jasmonate (MeJA), on in vitro shoot multiplication and the SGs content of S. rebaudiana. Different concentrations of these elicitors (50, 100, 200, and 300 mg/L) were added to Murashige and Skoog medium that had been supplemented with 2 mg/L 6-benzylaminopurine (BAP). The results showed that both biotic and abiotic elicitors increase shoot multiplication significantly when compared to the basal medium alone. Shoot length and shoot number increased by 70% and 94%, respectively, after adding 200 mg/L CH. Dry weight increased by 51%, 47%, and 36% after adding YE 50, CH 200, and MeJA 100 mg/L, respectively. Interestingly, total SGs content increased with the addition of MeJA 100, CH 200, and YE 50 (by 60%, 44%, and 40%, respectively). Stevioside (ST) and rebaudioside A (Reb A) concentrations, which are the final products of the SGs pathway, were both augmented by the addition of MeJA 100 and CH 200 mg/L. Moreover, these elicitors significantly enhanced the Reb A/ST ratio. Overall, the results indicate that elicitors? CH 200, MeJA 100, and YE 50 mg/L, in particular? can be effective stimulants for the production of biomass and the chemical composition of SGs content of in vitro S. rebaudiana. ? 2020 SAAB. Published by Elsevier B.V. All rights reserved

Transcript imaging and candidate gene strategy for the characterisation of Prunus/PPV interactions

International audienc

To cut or not to cut? That is the question in first year harvest of Stevia rebaudiana Bertoni production

Stevia rebaudiana (Bertoni) is a perennial crop from north Paraguay (humid subtropical climate), belonging to the Asteraceae family. Stevia is an emerging crop in Europe (mild climate), cultivated for its steviol glycosides (SG), natural sweeteners that are 300 times sweeter than sucrose which is the main agronomical and industrial interest of stevia. Recent studies showed that it is possible to cultivate stevia in mild climates as a perennial and economically viable crop. However, lack of knowledge on cropping system specific to perennial plants, the duration of cultivation, the overwintering and the impact of first-year crop establishment act as a disincentive to crop expansion. Harvest management through the impact of harvesting in the first year of establishment was investigated for agronomic traits over three years of production- for 15 stevia genotypes cultivated in the south-west of France. Two harvest modalities were compared: 2H when the plant is not harvested in the first year of establishment and 3H when the plant is harvested in the first year. The genotypes performance was assessed based on: regrowth rate after winter, SG yield (g/plant) through its two components of SG content (%w/w) and dry leaf biomass (g/plant), and the SG profile. Two cumulative variables, cumulated SG yield and cumulated dry leaf biomass, were also added to the study to obtain an overview of genotype performance during cultivation time and in both harvest modalities. The tested genotypes showed a wide range of response for overwintering, but with a significant decrease of 30 % survival rate for plants harvested in first year (3H). SG yield and dry leaf biomass results presented high variability among the different genotypes. These traits were also significantly impacted by the harvest modality, and a decrease in SG yield and dry leaf biomass was identified for plants harvested in first year (3H). No clear tendency was revealed for SG content or SG profile. Cumulative variables confirmed previous results showing a better SG yield and leaf biomass production for plants non-harvested during the first year (2H), at crop-life scale. Our results, on a wide range of genotypes, shed light on the agronomic management of Stevia rebaudiana in temperate conditions. They suggest the interest of a first year without harvest, allowing a better establishment of the crop, a better overwintering and a better cumulative yield

The use of green fluorescent protein-tagged recombinant plum pox virus (PPV) to study viral invasion in PPV/prunus interaction

International audienc