Application of conventional, biotechnological and genomics approaches for eggplant (solanum melongena.L). Breeding with a focus on bioactive phenolics

• Autores: Prashant Kaushik
• Directores de la Tesis: María de la O Plazas Avila (dir. tes.), Santiago Vilanova Navarro (dir. tes.), Jaime Prohens Tomás (dir. tes.)
• Lectura: En la Universitat Politècnica de València ( España ) en 2019
• Idioma: español
• Tribunal Calificador de la Tesis: Benito José Pineda Chaza (presid.), Jesús Muñoz Bertomeu (secret.), Vasileios Papasotiropoulos (voc.)
• Programa de doctorado: Programa de Doctorado en Biotecnología por la Universitat Politècnica de València
• Materias:
  • Ciencias agrarias
    • Agronomía
      • Hibridación de cultivos
    • Horticultura
      • Hortalizas
• Enlaces
  • Tesis en acceso abierto en: RiuNet
• Resumen

  • In the first chapter, a collection of six eggplant accessions, 21 accessions of 12 wild species (the only primary genepool species S. insanum and 11 secondary genepool species) and 45 interspecific hybrids of eggplant with wild species were characterized using 27 morphological descriptors and 20 fruit morphometric descriptors based on the phenomics tool Tomato Analyzer. We observed significant differences among the three groups with hybrids showing intermediate values for most of the descriptors. The wild species showed an extensive diversity for broadening the genetic base of eggplant. In the second chapter, the same material was characterized for the fruit phenolics, fruit flesh colour and browning related traits. Wild relatives showed greater variation for the fruit phenolics than cultivated eggplant. While, the predominant phenolic acid in cultivated eggplant was chlorogenic acid (>65.0%), in the wild relatives it was less 50% of HPLC chromatogram peak area. Cultivated varieties had lighter flesh colour and low polyphenol oxidase (PPO) activity. The interspecific hybrids were found to be intermediate for all the characters studied. Interestingly, we found no significant correlations between total phenolics or chlorogenic acid contents and fruit flesh browning. In the third chapter, we performed a Line by Tester (L ×T) genetic study using two cultivated lines one with oriental and another with occidental cytoplasm along with four testers representing three wild species namely, S. insanum, S.anguivi, and S. lichtensteinii. Further, we evaluated the material for 3 biochemical, 12 morphological and 8 Tomato Analyzer based descriptors. We found a significant amount of variation for all the 23 traits studied. The higher values for the SCA component were determined as compared to the GCA component. Overall, the secondary genepool testers were better for the biochemical traits improvement whereas, the primary genepool species was better for the morphological traits. In the fourth chapter, in order to gain information regarding the genetics of important traits in eggplant, we performed the first detailed genetic study of eggplant with 10 diverse eggplant genotypes among them an S. insanum accession, while the remaining nine were highly diverse shaped fruits of popular eggplant cultivars. When crossed in a half-diallel matting design 10 parents produced a set of 45 hybrids. We evaluated parents and hybrids for 14 morphological and 14 fruit morphometric traits descriptors. We also determined the genetic distances using 7,335 polymorphic SNP markers. In the study of the genetics of important morphological traits for hybrid development in eggplant, we found that genetic distance among parents had limited value to predict hybrid performance in this crop. Likewise, in the fifth chapter, we studied the fruit phenolics, fruit flesh colour and browning related traits in the same material. We determined that S. insanum accession INS2 displayed values highly significant for the total phenolics and CGA content. Significant specific and general combining ability effects were found for the biochemical traits studied. Similarly, the genetic distance among parents was nonsignificant to predict hybrids performance. Finally, in the sixth chapter, we have developed an agroinfiltration protocol for the transient expression of a gene in the eggplant fruit using GUS bearing; pCAMBIA1304 vector. Thereafter, to prove the usefulness of the protocol, we have used the eggplant hydroxycinnamoyl CoA-quinate transferase (SmHQT), which is the central enzyme studied to increase the chlorogenic acid content, in a gene construct with the specific promoter in a plant transformation vector (pBIN19). Also, in our cassette, we also co-expressed the P19 protein of Tomato bushy stunt virus to overexpress the protein. Overall, in this thesis, we have provided information regarding the wild relatives of eggplants from a morphological and biochemical prospective.