| Titre : | Réalisation de tests de laboratoire évaluant la bioactivité de formulations biostimulantes sur des plantes |
| Auteurs : | Madly Menda, Auteur ; Pierre Delaplace, Promoteur |
| Type de document : | Travail de fin d'études |
| Editeur : | Woluwe-Saint-Lambert : Haute École Léonard de Vinci, 2022 |
| Langues: | Français |
| Index. décimale : | TFE - Biologie médicale |
| Descripteurs : |
Autres descripteurs osmolalité |
| Mots-clés: | Biostimulant ; bioactivité |
| Résumé : |
A biostimulant is a substance that stimulates the absorption of nutrients in plants regardless of the nutrient content. It can improve how well the nutrients are used, the resistance to abiotic stress, the quality of the plant or the avaibility of nutrients confined in soil or the rhizosphere.
There are several categories of biostimulants and in the framework of the BioStimTest project, four of them are used in two bioassays: humic and fulvic acids, glycine betaine, silicium and the bacteria, Bacillus amyloliquefaciens. The bioassays were conducted on the plant Arabidopsis thaliana. The first bioassay had a purpose of testing their effectiveness to help the plant tolerate osmotic stress by using polyethylene glycol 6000 (PEG). A. thaliana seedlings were grown in phytostrips on an artificial substrate with different biostimulant concentrations. At the end of the bioassays, plant roots and leaves were photographed andthrough software analyses, leaf area, root length and root mass were estimated with proxy variables. Then, biostimulants products were used to see how they affected the rhizosphere acidification process. Bromocresol purple was used as an indicator to demonstrate the change in pH but also allowed us to measure that acidification with a spectrophotometer. Finally, few other tests consisted of using an osmometer to quantify the osmolality of biostimulant products and PEG solutions. This test is relevant to see if the contribution of the biostimulant formulas is minor compared to the PEG solutions. So far, the biostimulant products did not show any significant increase in the quality of the plant such as its resistance to stress, the mass and length of the root and leaf area except for one biostimulant made from humic and fulvic acids. It had a positive effect on the leaf area in the presence or in the absence of osmotic stress in the phytostrips bioassay. The results for the RAM bioassay are not available at this time. It was shown that the PEG does not have a consistent impact on the proxy variables in the phytostrips bioassay. This result challenges the relevance of this test for this project as well as the evaluation of the effectiveness of biostimulant products. Further research on the use of PEG to induce an osmotic stress and how the bioactivity of biostimulants could help a plant resist that stress needs to be done. |
| Accès : | Identifiez-vous avant d'accéder au document électronique |
| Disponible en ligne : | Oui |
| Lieu du stage : | Université de Liège-Gembloux Agro-Bio Tech-Plant Sciences |
| Département du TFE : | Biologie médicale |
Documents numériques (1)
 TFE - Biologie médicale Adobe Acrobat PDF |
