Hormonal control of the development and its interaction with the environment: study of a natural genetic variation in the water use efficiency

• Grant number: 06/04150-3
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• Start date: November 01, 2006
• End date: October 31, 2007
• Field of knowledge: Biological Sciences - Genetics - Plant Genetics
• Principal Investigator: Lázaro Eustaquio Pereira Peres
• Grantee: Ricardo Francisco Fornazier
• Host Institution: Escola Superior de Agricultura Luiz de Queiroz (ESALQ). Universidade de São Paulo (USP). Piracicaba , SP, Brazil

Abstract

Agriculture accounts for more than 70% of human water use, constituting one of the main targets for water economy in the XXI century. Although drought resistance is found in plants in the wild, for crops this trait must be balanced with satisfactory photosynthesis rates - a ratio known as Water Use Efficiency (WUE). Understanding of WUE is not restricted to the basic parameters of water relations and photosynthesis, but it is related to a large extent to the study of plant development. In spite of the fact that organ morphology responsible for water uptake (root system) or photosynthesis and water loss (shoot system) is known to be controlled by different hormonal classes, research has so far focused only on Abscisic Acid (ABA) and ethylene to study water relations and stress. In this sense, a broad study of the hormonal control of plant development and its impact in WUE has not yet been conducted. In previous work we selected diverse tomato (Lycopersicon esculentum) hormonal mutants, as well as a natural genetic variation on WUE derived from a drought resistant species (L. pennellii). This natural variation also proved to be associated to developmental alterations affecting stem height and stomatal density. The aim of the present project is to characterize this variation in WUE, to produce double mutants with hormonal mutants, to study oxidative stress responses therein, as well as performing genetic mapping using "introgression lines" derived from L. pennellii. Such proposal, besides being relevant as basic research, will provide interesting material for plant breeding programs in a key subject for Agriculture. (AU)