A method for testing drought tolerance in Fragaria based on fast screening for water deficit response and use of associated AFLP and EST candidate gene markers

Abstract

Drought stress is one of the most important environmental factors that limit plant growth and development, thus reducing yield. The objective of the present research was to correlate the genetic structure of different Fragaria genotypes, as assessed by Expressed Sequence Tag (EST) and Amplified Fragment Length Polymorphism (AFLP) markers, and plant responses to drought stress. Firstly, physiological parameters related to the plant response to drought stress such as leaf relative water content (RWC) and water losing rate (WLR) were measured. WLR and RWC were compared for 20 cultivars of the octaploid Fragaria 9 ananassa, two ecotypes of the diploid species F. vesca and one octaploid species F. chiloensis. These parameters could discriminate genotypes showing a contrasting response to water stress. Secondly, AFLP and ESTs were compared in terms of their information content and efficiency in the study of genetic diversity and relationships among these 23 Fragaria genotypes. To evaluate the genetic basis for the observed variation in the measured physiological parameter, the effect of specific AFLP/EST loci on WLR and RWC for the different Fragaria genotypes was quantified by Kruskal-Wallis analysis. By Mantel testing, the hierarchical clustering of the Fragaria genotypes based on associated EST or AFLP markers was compared to the observed eco-physiological relevant grouping. A better discriminating capacity for associated markers was noted, enabling a functional marker selection approach to screen the strawberry gene pool for drought tolerance. Correlation of EST markers to leaf RWC and WLR enforces them as potential candidate genes in control of plant responses to drought stress in Fragaria sp.

Screening for Eruca genotypes tolerant to polyethylene glycol-simulated drought stress based on the principal component and cluster analyses of seed germination and early seedling growth

“…Methods of screening for drought tolerance within a large number of genotypes should be easy, fast, accurate and inexpensive (Grzesiak et al , 2003). Field/pot screening for roots is destructive, costly and laborious when a large number of genotypes is involved (Razavi et al , 2011). Germinating seeds under PEG-simulated drought stress have several advantages compared with field/pot screenings, including: easy to score root and shoot traits; controlled environmental conditions, thus increasing the repeatability; screening large numbers of genotypes in a small space within a short time; precise control of the concentration of mineral nutrients (Kumar et al , 2014).…”

Anchoring Linkage Groups of the Rosa Genetic Map to Physical Chromosomes with Tyramide-FISH and EST-SNP Markers

“…DNA of Rosa wichurana , Rosa ‘Yesterday’ and their hybrids was extracted from young leaves using the Qiagen DNeasy Plant Mini Kit (Chatsworth, CA). The genes PAL , P5CS and OOMT were isolated according to Razavi et al [79] starting from ESTs available in the Genome Database of Rosaceae [80] . These genes are known to be involved in abiotic stress response ( Phenylalanine Ammonia Lyase ( PAL ) and Pyrroline - 5 - Carboxylate Synthase ( P5CS ), [81] , [82] ) and rose scent production ( Orcinol O - Methyl Transferase ( OOMT ), [83] ), which are important traits for roses.…”

Fragaria: A genus with deep historical roots and ripe for evolutionary and ecological insights

“…This variation represents a potential source of genetic variation for climatic tolerance, disease/pest resistance, and yield‐associated traits (Hancock and Luby, 1993; Stewart and Folta, 2010). Furthermore, this natural variation (Table 2) provides the opportunity to investigate the ecological genomics of traits such as flowering time (Mouhu et al, 2009), drought (Razavi etal., 2011; Šurbanovski et al, 2013), and frost tolerance (Sønsteby and Heide, 2011).…”